# RecyclerView.LayoutManager
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
belongs to Maven artifact com.android.support:recyclerview-v7:28.0.0-alpha1
Summary:[Nested Classes](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#nestedclasses)\|[XML Attrs](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#lattrs)\|[Ctors](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#pubctors)\|[Methods](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#pubmethods)\|[Inherited Methods](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#inhmethods)\|[\[Expand All\]](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#)
# RecyclerView.LayoutManager
| This package is part of the Android[support library](https://developer.android.com/topic/libraries/support-library)which is no longer maintained. The support library has been superseded by[AndroidX](https://developer.android.com/jetpack/androidx)which is part of[Jetpack](https://developer.android.com/jetpack). We recommend using the AndroidX libraries in all new projects. You should also consider[migrating](https://developer.android.com/jetpack/androidx/migrate)existing projects to AndroidX. To find the AndroidX class that maps to this deprecated class, see the AndroidX support library[class mappings](https://developer.android.com/jetpack/androidx/migrate/class-mappings).
`
public
static
abstract
class
RecyclerView.LayoutManager
`
`
extends Object
``
`
|---|------------------------------------------------------|
| java.lang.Object ||
| ↳ | android.support.v7.widget.RecyclerView.LayoutManager |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#)Known Direct Subclasses [LinearLayoutManager](https://developer.android.com/reference/android/support/v7/widget/LinearLayoutManager),[StaggeredGridLayoutManager](https://developer.android.com/reference/android/support/v7/widget/StaggeredGridLayoutManager) |----------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | [LinearLayoutManager](https://developer.android.com/reference/android/support/v7/widget/LinearLayoutManager) | A[RecyclerView.LayoutManager](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager)implementation which provides similar functionality to[ListView](https://developer.android.com/reference/android/widget/ListView.html). | | [StaggeredGridLayoutManager](https://developer.android.com/reference/android/support/v7/widget/StaggeredGridLayoutManager) | A LayoutManager that lays out children in a staggered grid formation. | |
|---|---|
| [](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#)Known Indirect Subclasses [GridLayoutManager](https://developer.android.com/reference/android/support/v7/widget/GridLayoutManager),[WearableLinearLayoutManager](https://developer.android.com/reference/android/support/wear/widget/WearableLinearLayoutManager) |--------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | [GridLayoutManager](https://developer.android.com/reference/android/support/v7/widget/GridLayoutManager) | A[RecyclerView.LayoutManager](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager)implementations that lays out items in a grid. | | [WearableLinearLayoutManager](https://developer.android.com/reference/android/support/wear/widget/WearableLinearLayoutManager) | This wear-specific implementation of[LinearLayoutManager](https://developer.android.com/reference/android/support/v7/widget/LinearLayoutManager)provides basic offsetting logic for updating child layout. | ||
*** ** * ** ***
A`LayoutManager`is responsible for measuring and positioning item views within a`RecyclerView`as well as determining the policy for when to recycle item views that are no longer visible to the user. By changing the`LayoutManager`a`RecyclerView`can be used to implement a standard vertically scrolling list, a uniform grid, staggered grids, horizontally scrolling collections and more. Several stock layout managers are provided for general use.
If the LayoutManager specifies a default constructor or one with the signature ([Context](https://developer.android.com/reference/android/content/Context.html),[AttributeSet](https://developer.android.com/reference/android/util/AttributeSet.html),`int`,`int`), RecyclerView will instantiate and set the LayoutManager when being inflated. Most used properties can be then obtained from[getProperties(Context, AttributeSet, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getProperties(android.content.Context, android.util.AttributeSet, int, int)). In case a LayoutManager specifies both constructors, the non-default constructor will take precedence.
## Summary
| ### Nested classes ||
|--------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| ` interface` | [RecyclerView.LayoutManager.LayoutPrefetchRegistry](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager.LayoutPrefetchRegistry) Interface for LayoutManagers to request items to be prefetched, based on position, with specified distance from viewport, which indicates priority. |
| ` class` | [RecyclerView.LayoutManager.Properties](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager.Properties) Some general properties that a LayoutManager may want to use. |
| ### XML attributes ||
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---|
| [`RecyclerView_android_orientation`](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#attr_RecyclerView_android_orientation) | |
| [`RecyclerView_reverseLayout`](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#attr_RecyclerView_reverseLayout) | |
| [`RecyclerView_spanCount`](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#attr_RecyclerView_spanCount) | |
| [`RecyclerView_stackFromEnd`](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#attr_RecyclerView_stackFromEnd) | |
| ### Public constructors ||
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------|---|
| ` `[RecyclerView.LayoutManager](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#RecyclerView.LayoutManager())`() ` |
| ### Public methods ||
|------------------------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| ` void` | ` `[addDisappearingView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#addDisappearingView(android.view.View, int))`(`[View](https://developer.android.com/reference/android/view/View.html)` child, int index) ` To be called only during[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))to add a view to the layout that is known to be going away, either because it has been[removed](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Adapter#notifyItemRemoved(int))or because it is actually not in the visible portion of the container but is being laid out in order to inform RecyclerView in how to animate the item out of view. |
| ` void` | ` `[addDisappearingView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#addDisappearingView(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` To be called only during[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))to add a view to the layout that is known to be going away, either because it has been[removed](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Adapter#notifyItemRemoved(int))or because it is actually not in the visible portion of the container but is being laid out in order to inform RecyclerView in how to animate the item out of view. |
| ` void` | ` `[addView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#addView(android.view.View, int))`(`[View](https://developer.android.com/reference/android/view/View.html)` child, int index) ` Add a view to the currently attached RecyclerView if needed. |
| ` void` | ` `[addView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#addView(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` Add a view to the currently attached RecyclerView if needed. |
| ` void` | ` `[assertInLayoutOrScroll](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#assertInLayoutOrScroll(java.lang.String))`(String message) ` Checks if RecyclerView is in the middle of a layout or scroll and throws an[IllegalStateException](https://developer.android.com/reference/java/lang/IllegalStateException)if it**is not**. |
| ` void` | ` `[assertNotInLayoutOrScroll](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#assertNotInLayoutOrScroll(java.lang.String))`(String message) ` Checks if RecyclerView is in the middle of a layout or scroll and throws an[IllegalStateException](https://developer.android.com/reference/java/lang/IllegalStateException)if it**is**. |
| ` void` | ` `[attachView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#attachView(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` Reattach a previously[detached](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachView(android.view.View))view. |
| ` void` | ` `[attachView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#attachView(android.view.View, int))`(`[View](https://developer.android.com/reference/android/view/View.html)` child, int index) ` Reattach a previously[detached](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachView(android.view.View))view. |
| ` void` | ` `[attachView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#attachView(android.view.View, int, android.support.v7.widget.RecyclerView.LayoutParams))`(`[View](https://developer.android.com/reference/android/view/View.html)` child, int index, `[RecyclerView.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutParams)` lp) ` Reattach a previously[detached](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachView(android.view.View))view. |
| ` void` | ` `[calculateItemDecorationsForChild](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#calculateItemDecorationsForChild(android.view.View, android.graphics.Rect))`(`[View](https://developer.android.com/reference/android/view/View.html)` child, `[Rect](https://developer.android.com/reference/android/graphics/Rect.html)` outRect) ` Calculates the item decor insets applied to the given child and updates the provided Rect instance with the inset values. |
| ` boolean` | ` `[canScrollHorizontally](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#canScrollHorizontally())`() ` Query if horizontal scrolling is currently supported. |
| ` boolean` | ` `[canScrollVertically](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#canScrollVertically())`() ` Query if vertical scrolling is currently supported. |
| ` boolean` | ` `[checkLayoutParams](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#checkLayoutParams(android.support.v7.widget.RecyclerView.LayoutParams))`(`[RecyclerView.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutParams)` lp) ` Determines the validity of the supplied LayoutParams object. |
| ` static int` | ` `[chooseSize](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#chooseSize(int, int, int))`(int spec, int desired, int min) ` Chooses a size from the given specs and parameters that is closest to the desired size and also complies with the spec. |
| ` void` | ` `[collectAdjacentPrefetchPositions](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#collectAdjacentPrefetchPositions(int, int, android.support.v7.widget.RecyclerView.State, android.support.v7.widget.RecyclerView.LayoutManager.LayoutPrefetchRegistry))`(int dx, int dy, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state, `[RecyclerView.LayoutManager.LayoutPrefetchRegistry](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager.LayoutPrefetchRegistry)` layoutPrefetchRegistry) ` Gather all positions from the LayoutManager to be prefetched, given specified momentum. |
| ` void` | ` `[collectInitialPrefetchPositions](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#collectInitialPrefetchPositions(int, android.support.v7.widget.RecyclerView.LayoutManager.LayoutPrefetchRegistry))`(int adapterItemCount, `[RecyclerView.LayoutManager.LayoutPrefetchRegistry](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager.LayoutPrefetchRegistry)` layoutPrefetchRegistry) ` Gather all positions from the LayoutManager to be prefetched in preperation for its RecyclerView to come on screen, due to the movement of another, containing RecyclerView. |
| ` int` | ` `[computeHorizontalScrollExtent](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#computeHorizontalScrollExtent(android.support.v7.widget.RecyclerView.State))`(`[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state) `
Override this method if you want to support scroll bars. |
| ` int` | ` `[computeHorizontalScrollOffset](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#computeHorizontalScrollOffset(android.support.v7.widget.RecyclerView.State))`(`[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state) `
Override this method if you want to support scroll bars. |
| ` int` | ` `[computeHorizontalScrollRange](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#computeHorizontalScrollRange(android.support.v7.widget.RecyclerView.State))`(`[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state) `
Override this method if you want to support scroll bars. |
| ` int` | ` `[computeVerticalScrollExtent](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#computeVerticalScrollExtent(android.support.v7.widget.RecyclerView.State))`(`[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state) `
Override this method if you want to support scroll bars. |
| ` int` | ` `[computeVerticalScrollOffset](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#computeVerticalScrollOffset(android.support.v7.widget.RecyclerView.State))`(`[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state) `
Override this method if you want to support scroll bars. |
| ` int` | ` `[computeVerticalScrollRange](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#computeVerticalScrollRange(android.support.v7.widget.RecyclerView.State))`(`[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state) `
Override this method if you want to support scroll bars. |
| ` void` | ` `[detachAndScrapAttachedViews](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachAndScrapAttachedViews(android.support.v7.widget.RecyclerView.Recycler))`(`[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler) ` Temporarily detach and scrap all currently attached child views. |
| ` void` | ` `[detachAndScrapView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachAndScrapView(android.view.View, android.support.v7.widget.RecyclerView.Recycler))`(`[View](https://developer.android.com/reference/android/view/View.html)` child, `[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler) ` Detach a child view and add it to a[Recycler's](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)scrap heap. |
| ` void` | ` `[detachAndScrapViewAt](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachAndScrapViewAt(int, android.support.v7.widget.RecyclerView.Recycler))`(int index, `[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler) ` Detach a child view and add it to a[Recycler's](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)scrap heap. |
| ` void` | ` `[detachView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachView(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` Temporarily detach a child view. |
| ` void` | ` `[detachViewAt](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachViewAt(int))`(int index) ` Temporarily detach a child view. |
| ` void` | ` `[endAnimation](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#endAnimation(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` view) ` Ends all animations on the view created by the[RecyclerView.ItemAnimator](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemAnimator). |
| ` `[View](https://developer.android.com/reference/android/view/View.html) | ` `[findContainingItemView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#findContainingItemView(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` view) ` Traverses the ancestors of the given view and returns the item view that contains it and also a direct child of the LayoutManager. |
| ` `[View](https://developer.android.com/reference/android/view/View.html) | ` `[findViewByPosition](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#findViewByPosition(int))`(int position) ` Finds the view which represents the given adapter position. |
| ` abstract `[RecyclerView.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutParams) | ` `[generateDefaultLayoutParams](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#generateDefaultLayoutParams())`() ` Create a default`LayoutParams`object for a child of the RecyclerView. |
| ` `[RecyclerView.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutParams) | ` `[generateLayoutParams](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#generateLayoutParams(android.content.Context, android.util.AttributeSet))`(`[Context](https://developer.android.com/reference/android/content/Context.html)` c, `[AttributeSet](https://developer.android.com/reference/android/util/AttributeSet.html)` attrs) ` Create a LayoutParams object suitable for this LayoutManager from an inflated layout resource. |
| ` `[RecyclerView.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutParams) | ` `[generateLayoutParams](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#generateLayoutParams(android.view.ViewGroup.LayoutParams))`(`[ViewGroup.LayoutParams](https://developer.android.com/reference/android/view/ViewGroup.LayoutParams.html)` lp) ` Create a LayoutParams object suitable for this LayoutManager, copying relevant values from the supplied LayoutParams object if possible. |
| ` int` | ` `[getBaseline](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getBaseline())`() ` Returns offset of the RecyclerView's text baseline from the its top boundary. |
| ` int` | ` `[getBottomDecorationHeight](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getBottomDecorationHeight(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` Returns the total height of item decorations applied to child's bottom. |
| ` `[View](https://developer.android.com/reference/android/view/View.html) | ` `[getChildAt](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getChildAt(int))`(int index) ` Return the child view at the given index |
| ` int` | ` `[getChildCount](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getChildCount())`() ` Return the current number of child views attached to the parent RecyclerView. |
| ` static int` | ` `[getChildMeasureSpec](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getChildMeasureSpec(int, int, int, int, boolean))`(int parentSize, int parentMode, int padding, int childDimension, boolean canScroll) ` Calculate a MeasureSpec value for measuring a child view in one dimension. |
| ` static int` | ` `[getChildMeasureSpec](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getChildMeasureSpec(int, int, int, boolean))`(int parentSize, int padding, int childDimension, boolean canScroll) ` *This method was deprecated in API level 24.1.0. use[getChildMeasureSpec(int, int, int, int, boolean)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getChildMeasureSpec(int, int, int, int, boolean))* |
| ` boolean` | ` `[getClipToPadding](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getClipToPadding())`() ` Check if the RecyclerView is configured to clip child views to its padding. |
| ` int` | ` `[getColumnCountForAccessibility](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getColumnCountForAccessibility(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))`(`[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state) ` Returns the number of columns for accessibility. |
| ` int` | ` `[getDecoratedBottom](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedBottom(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` Returns the bottom edge of the given child view within its parent, offset by any applied[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration). |
| ` void` | ` `[getDecoratedBoundsWithMargins](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedBoundsWithMargins(android.view.View, android.graphics.Rect))`(`[View](https://developer.android.com/reference/android/view/View.html)` view, `[Rect](https://developer.android.com/reference/android/graphics/Rect.html)` outBounds) ` Returns the bounds of the view including its decoration and margins. |
| ` int` | ` `[getDecoratedLeft](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedLeft(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` Returns the left edge of the given child view within its parent, offset by any applied[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration). |
| ` int` | ` `[getDecoratedMeasuredHeight](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedMeasuredHeight(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` Returns the measured height of the given child, plus the additional size of any insets applied by[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration). |
| ` int` | ` `[getDecoratedMeasuredWidth](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedMeasuredWidth(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` Returns the measured width of the given child, plus the additional size of any insets applied by[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration). |
| ` int` | ` `[getDecoratedRight](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedRight(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` Returns the right edge of the given child view within its parent, offset by any applied[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration). |
| ` int` | ` `[getDecoratedTop](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedTop(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` Returns the top edge of the given child view within its parent, offset by any applied[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration). |
| ` `[View](https://developer.android.com/reference/android/view/View.html) | ` `[getFocusedChild](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getFocusedChild())`() ` Returns the item View which has or contains focus. |
| ` int` | ` `[getHeight](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getHeight())`() ` Returns the height that is currently relevant to the LayoutManager. |
| ` int` | ` `[getHeightMode](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getHeightMode())`() ` Return the height measurement spec mode that is currently relevant to the LayoutManager. |
| ` int` | ` `[getItemCount](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getItemCount())`() ` Returns the number of items in the adapter bound to the parent RecyclerView. |
| ` int` | ` `[getItemViewType](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getItemViewType(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` view) ` Returns the View type defined by the adapter. |
| ` int` | ` `[getLayoutDirection](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getLayoutDirection())`() ` Returns the resolved layout direction for this RecyclerView. |
| ` int` | ` `[getLeftDecorationWidth](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getLeftDecorationWidth(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` Returns the total width of item decorations applied to child's left. |
| ` int` | ` `[getMinimumHeight](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getMinimumHeight())`() ` |
| ` int` | ` `[getMinimumWidth](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getMinimumWidth())`() ` |
| ` int` | ` `[getPaddingBottom](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getPaddingBottom())`() ` Return the bottom padding of the parent RecyclerView |
| ` int` | ` `[getPaddingEnd](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getPaddingEnd())`() ` Return the end padding of the parent RecyclerView |
| ` int` | ` `[getPaddingLeft](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getPaddingLeft())`() ` Return the left padding of the parent RecyclerView |
| ` int` | ` `[getPaddingRight](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getPaddingRight())`() ` Return the right padding of the parent RecyclerView |
| ` int` | ` `[getPaddingStart](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getPaddingStart())`() ` Return the start padding of the parent RecyclerView |
| ` int` | ` `[getPaddingTop](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getPaddingTop())`() ` Return the top padding of the parent RecyclerView |
| ` int` | ` `[getPosition](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getPosition(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` view) ` Returns the adapter position of the item represented by the given View. |
| ` static `[RecyclerView.LayoutManager.Properties](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager.Properties) | ` `[getProperties](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getProperties(android.content.Context, android.util.AttributeSet, int, int))`(`[Context](https://developer.android.com/reference/android/content/Context.html)` context, `[AttributeSet](https://developer.android.com/reference/android/util/AttributeSet.html)` attrs, int defStyleAttr, int defStyleRes) ` Parse the xml attributes to get the most common properties used by layout managers. |
| ` int` | ` `[getRightDecorationWidth](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getRightDecorationWidth(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` Returns the total width of item decorations applied to child's right. |
| ` int` | ` `[getRowCountForAccessibility](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getRowCountForAccessibility(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))`(`[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state) ` Returns the number of rows for accessibility. |
| ` int` | ` `[getSelectionModeForAccessibility](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getSelectionModeForAccessibility(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))`(`[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state) ` Returns the selection mode for accessibility. |
| ` int` | ` `[getTopDecorationHeight](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getTopDecorationHeight(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` Returns the total height of item decorations applied to child's top. |
| ` void` | ` `[getTransformedBoundingBox](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getTransformedBoundingBox(android.view.View, boolean, android.graphics.Rect))`(`[View](https://developer.android.com/reference/android/view/View.html)` child, boolean includeDecorInsets, `[Rect](https://developer.android.com/reference/android/graphics/Rect.html)` out) ` Calculates the bounding box of the View while taking into account its matrix changes (translation, scale etc) with respect to the RecyclerView. |
| ` int` | ` `[getWidth](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getWidth())`() ` Returns the width that is currently relevant to the LayoutManager. |
| ` int` | ` `[getWidthMode](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getWidthMode())`() ` Return the width measurement spec mode that is currently relevant to the LayoutManager. |
| ` boolean` | ` `[hasFocus](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#hasFocus())`() ` Returns true if the RecyclerView this LayoutManager is bound to has or contains focus. |
| ` void` | ` `[ignoreView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#ignoreView(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` view) ` Flags a view so that it will not be scrapped or recycled. |
| ` boolean` | ` `[isAttachedToWindow](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isAttachedToWindow())`() ` Returns whether LayoutManager is currently attached to a RecyclerView which is attached to a window. |
| ` boolean` | ` `[isAutoMeasureEnabled](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isAutoMeasureEnabled())`() ` Returns whether the measuring pass of layout should use the AutoMeasure mechanism of[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)or if it should be done by the LayoutManager's implementation of[onMeasure(Recycler, State, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onMeasure(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State, int, int)). |
| ` boolean` | ` `[isFocused](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isFocused())`() ` Returns true if the RecyclerView this LayoutManager is bound to has focus. |
| ` final boolean` | ` `[isItemPrefetchEnabled](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isItemPrefetchEnabled())`() ` Sets whether the LayoutManager should be queried for views outside of its viewport while the UI thread is idle between frames. |
| ` boolean` | ` `[isLayoutHierarchical](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isLayoutHierarchical(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))`(`[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state) ` Returns whether layout is hierarchical or not to be used for accessibility. |
| ` boolean` | ` `[isMeasurementCacheEnabled](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isMeasurementCacheEnabled())`() ` In addition to the View Framework's measurement cache, RecyclerView uses its own additional measurement cache for its children to avoid re-measuring them when not necessary. |
| ` boolean` | ` `[isSmoothScrolling](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isSmoothScrolling())`() ` |
| ` boolean` | ` `[isViewPartiallyVisible](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isViewPartiallyVisible(android.view.View, boolean, boolean))`(`[View](https://developer.android.com/reference/android/view/View.html)` child, boolean completelyVisible, boolean acceptEndPointInclusion) ` Returns whether the given child view is partially or fully visible within the padded bounded area of RecyclerView, depending on the input parameters. |
| ` void` | ` `[layoutDecorated](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#layoutDecorated(android.view.View, int, int, int, int))`(`[View](https://developer.android.com/reference/android/view/View.html)` child, int left, int top, int right, int bottom) ` Lay out the given child view within the RecyclerView using coordinates that include any current[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration). |
| ` void` | ` `[layoutDecoratedWithMargins](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#layoutDecoratedWithMargins(android.view.View, int, int, int, int))`(`[View](https://developer.android.com/reference/android/view/View.html)` child, int left, int top, int right, int bottom) ` Lay out the given child view within the RecyclerView using coordinates that include any current[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration)and margins. |
| ` void` | ` `[measureChild](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#measureChild(android.view.View, int, int))`(`[View](https://developer.android.com/reference/android/view/View.html)` child, int widthUsed, int heightUsed) ` Measure a child view using standard measurement policy, taking the padding of the parent RecyclerView and any added item decorations into account. |
| ` void` | ` `[measureChildWithMargins](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#measureChildWithMargins(android.view.View, int, int))`(`[View](https://developer.android.com/reference/android/view/View.html)` child, int widthUsed, int heightUsed) ` Measure a child view using standard measurement policy, taking the padding of the parent RecyclerView, any added item decorations and the child margins into account. |
| ` void` | ` `[moveView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#moveView(int, int))`(int fromIndex, int toIndex) ` Moves a View from one position to another. |
| ` void` | ` `[offsetChildrenHorizontal](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#offsetChildrenHorizontal(int))`(int dx) ` Offset all child views attached to the parent RecyclerView by dx pixels along the horizontal axis. |
| ` void` | ` `[offsetChildrenVertical](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#offsetChildrenVertical(int))`(int dy) ` Offset all child views attached to the parent RecyclerView by dy pixels along the vertical axis. |
| ` void` | ` `[onAdapterChanged](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onAdapterChanged(android.support.v7.widget.RecyclerView.Adapter, android.support.v7.widget.RecyclerView.Adapter))`(`[Adapter](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Adapter)` oldAdapter, `[Adapter](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Adapter)` newAdapter) ` Called if the RecyclerView this LayoutManager is bound to has a different adapter set via[setAdapter(Adapter)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#setAdapter(android.support.v7.widget.RecyclerView.Adapter))or[swapAdapter(Adapter, boolean)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#swapAdapter(android.support.v7.widget.RecyclerView.Adapter, boolean)). |
| ` boolean` | ` `[onAddFocusables](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onAddFocusables(android.support.v7.widget.RecyclerView, java.util.ArrayList, int, int))`(`[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)` recyclerView, ArrayList<`[View](https://developer.android.com/reference/android/view/View.html)`> views, int direction, int focusableMode) ` Called to populate focusable views within the RecyclerView. |
| ` void` | ` `[onAttachedToWindow](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onAttachedToWindow(android.support.v7.widget.RecyclerView))`(`[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)` view) ` Called when this LayoutManager is both attached to a RecyclerView and that RecyclerView is attached to a window. |
| ` void` | ` `[onDetachedFromWindow](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onDetachedFromWindow(android.support.v7.widget.RecyclerView, android.support.v7.widget.RecyclerView.Recycler))`(`[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)` view, `[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler) ` Called when this LayoutManager is detached from its parent RecyclerView or when its parent RecyclerView is detached from its window. |
| ` void` | ` `[onDetachedFromWindow](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onDetachedFromWindow(android.support.v7.widget.RecyclerView))`(`[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)` view) ` *This method was deprecated in API level 22.1.0. override[onDetachedFromWindow(RecyclerView, Recycler)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onDetachedFromWindow(android.support.v7.widget.RecyclerView, android.support.v7.widget.RecyclerView.Recycler))* |
| ` `[View](https://developer.android.com/reference/android/view/View.html) | ` `[onFocusSearchFailed](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onFocusSearchFailed(android.view.View, int, android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))`(`[View](https://developer.android.com/reference/android/view/View.html)` focused, int direction, `[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state) ` Called when searching for a focusable view in the given direction has failed for the current content of the RecyclerView. |
| ` void` | ` `[onInitializeAccessibilityEvent](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onInitializeAccessibilityEvent(android.view.accessibility.AccessibilityEvent))`(`[AccessibilityEvent](https://developer.android.com/reference/android/view/accessibility/AccessibilityEvent.html)` event) ` |
| ` void` | ` `[onInitializeAccessibilityEvent](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onInitializeAccessibilityEvent(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State, android.view.accessibility.AccessibilityEvent))`(`[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state, `[AccessibilityEvent](https://developer.android.com/reference/android/view/accessibility/AccessibilityEvent.html)` event) ` Called by the accessibility delegate to initialize an accessibility event. |
| ` void` | ` `[onInitializeAccessibilityNodeInfo](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onInitializeAccessibilityNodeInfo(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State, android.support.v4.view.accessibility.AccessibilityNodeInfoCompat))`(`[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state, `[AccessibilityNodeInfoCompat](https://developer.android.com/reference/android/support/v4/view/accessibility/AccessibilityNodeInfoCompat)` info) ` Called by the AccessibilityDelegate when the information about the current layout should be populated. |
| ` void` | ` `[onInitializeAccessibilityNodeInfoForItem](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onInitializeAccessibilityNodeInfoForItem(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State, android.view.View, android.support.v4.view.accessibility.AccessibilityNodeInfoCompat))`(`[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state, `[View](https://developer.android.com/reference/android/view/View.html)` host, `[AccessibilityNodeInfoCompat](https://developer.android.com/reference/android/support/v4/view/accessibility/AccessibilityNodeInfoCompat)` info) ` Called by the AccessibilityDelegate when the accessibility information for a specific item should be populated. |
| ` `[View](https://developer.android.com/reference/android/view/View.html) | ` `[onInterceptFocusSearch](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onInterceptFocusSearch(android.view.View, int))`(`[View](https://developer.android.com/reference/android/view/View.html)` focused, int direction) ` This method gives a LayoutManager an opportunity to intercept the initial focus search before the default behavior of[FocusFinder](https://developer.android.com/reference/android/view/FocusFinder.html)is used. |
| ` void` | ` `[onItemsAdded](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onItemsAdded(android.support.v7.widget.RecyclerView, int, int))`(`[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)` recyclerView, int positionStart, int itemCount) ` Called when items have been added to the adapter. |
| ` void` | ` `[onItemsChanged](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onItemsChanged(android.support.v7.widget.RecyclerView))`(`[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)` recyclerView) ` Called in response to a call to[notifyDataSetChanged()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Adapter#notifyDataSetChanged())or[swapAdapter(Adapter, boolean)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#swapAdapter(android.support.v7.widget.RecyclerView.Adapter, boolean))()} and signals that the the entire data set has changed. |
| ` void` | ` `[onItemsMoved](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onItemsMoved(android.support.v7.widget.RecyclerView, int, int, int))`(`[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)` recyclerView, int from, int to, int itemCount) ` Called when an item is moved withing the adapter. |
| ` void` | ` `[onItemsRemoved](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onItemsRemoved(android.support.v7.widget.RecyclerView, int, int))`(`[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)` recyclerView, int positionStart, int itemCount) ` Called when items have been removed from the adapter. |
| ` void` | ` `[onItemsUpdated](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onItemsUpdated(android.support.v7.widget.RecyclerView, int, int))`(`[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)` recyclerView, int positionStart, int itemCount) ` Called when items have been changed in the adapter. |
| ` void` | ` `[onItemsUpdated](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onItemsUpdated(android.support.v7.widget.RecyclerView, int, int, java.lang.Object))`(`[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)` recyclerView, int positionStart, int itemCount, Object payload) ` Called when items have been changed in the adapter and with optional payload. |
| ` void` | ` `[onLayoutChildren](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))`(`[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state) ` Lay out all relevant child views from the given adapter. |
| ` void` | ` `[onLayoutCompleted](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutCompleted(android.support.v7.widget.RecyclerView.State))`(`[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state) ` Called after a full layout calculation is finished. |
| ` void` | ` `[onMeasure](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onMeasure(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State, int, int))`(`[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state, int widthSpec, int heightSpec) ` Measure the attached RecyclerView. |
| ` boolean` | ` `[onRequestChildFocus](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onRequestChildFocus(android.support.v7.widget.RecyclerView, android.view.View, android.view.View))`(`[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)` parent, `[View](https://developer.android.com/reference/android/view/View.html)` child, `[View](https://developer.android.com/reference/android/view/View.html)` focused) ` *This method was deprecated in API level 22.1.0. Use[onRequestChildFocus(RecyclerView, State, View, View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onRequestChildFocus(android.support.v7.widget.RecyclerView, android.support.v7.widget.RecyclerView.State, android.view.View, android.view.View))* |
| ` boolean` | ` `[onRequestChildFocus](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onRequestChildFocus(android.support.v7.widget.RecyclerView, android.support.v7.widget.RecyclerView.State, android.view.View, android.view.View))`(`[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)` parent, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state, `[View](https://developer.android.com/reference/android/view/View.html)` child, `[View](https://developer.android.com/reference/android/view/View.html)` focused) ` Called when a descendant view of the RecyclerView requests focus. |
| ` void` | ` `[onRestoreInstanceState](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onRestoreInstanceState(android.os.Parcelable))`(`[Parcelable](https://developer.android.com/reference/android/os/Parcelable.html)` state) ` |
| ` `[Parcelable](https://developer.android.com/reference/android/os/Parcelable.html) | ` `[onSaveInstanceState](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onSaveInstanceState())`() `
Called when the LayoutManager should save its state. |
| ` void` | ` `[onScrollStateChanged](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onScrollStateChanged(int))`(int state) ` RecyclerView calls this method to notify LayoutManager that scroll state has changed. |
| ` boolean` | ` `[performAccessibilityAction](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#performAccessibilityAction(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State, int, android.os.Bundle))`(`[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state, int action, `[Bundle](https://developer.android.com/reference/android/os/Bundle.html)` args) ` Called by AccessibilityDelegate when an action is requested from the RecyclerView. |
| ` boolean` | ` `[performAccessibilityActionForItem](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#performAccessibilityActionForItem(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State, android.view.View, int, android.os.Bundle))`(`[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state, `[View](https://developer.android.com/reference/android/view/View.html)` view, int action, `[Bundle](https://developer.android.com/reference/android/os/Bundle.html)` args) ` Called by AccessibilityDelegate when an accessibility action is requested on one of the children of LayoutManager. |
| ` void` | ` `[postOnAnimation](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#postOnAnimation(java.lang.Runnable))`(Runnable action) ` Causes the Runnable to execute on the next animation time step. |
| ` void` | ` `[removeAllViews](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#removeAllViews())`() ` Remove all views from the currently attached RecyclerView. |
| ` void` | ` `[removeAndRecycleAllViews](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#removeAndRecycleAllViews(android.support.v7.widget.RecyclerView.Recycler))`(`[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler) ` Removes all views and recycles them using the given recycler. |
| ` void` | ` `[removeAndRecycleView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#removeAndRecycleView(android.view.View, android.support.v7.widget.RecyclerView.Recycler))`(`[View](https://developer.android.com/reference/android/view/View.html)` child, `[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler) ` Remove a child view and recycle it using the given Recycler. |
| ` void` | ` `[removeAndRecycleViewAt](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#removeAndRecycleViewAt(int, android.support.v7.widget.RecyclerView.Recycler))`(int index, `[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler) ` Remove a child view and recycle it using the given Recycler. |
| ` boolean` | ` `[removeCallbacks](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#removeCallbacks(java.lang.Runnable))`(Runnable action) ` Removes the specified Runnable from the message queue. |
| ` void` | ` `[removeDetachedView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#removeDetachedView(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` Finish removing a view that was previously temporarily[detached](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachView(android.view.View)). |
| ` void` | ` `[removeView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#removeView(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` child) ` Remove a view from the currently attached RecyclerView if needed. |
| ` void` | ` `[removeViewAt](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#removeViewAt(int))`(int index) ` Remove a view from the currently attached RecyclerView if needed. |
| ` boolean` | ` `[requestChildRectangleOnScreen](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#requestChildRectangleOnScreen(android.support.v7.widget.RecyclerView, android.view.View, android.graphics.Rect, boolean, boolean))`(`[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)` parent, `[View](https://developer.android.com/reference/android/view/View.html)` child, `[Rect](https://developer.android.com/reference/android/graphics/Rect.html)` rect, boolean immediate, boolean focusedChildVisible) ` Requests that the given child of the RecyclerView be positioned onto the screen. |
| ` boolean` | ` `[requestChildRectangleOnScreen](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#requestChildRectangleOnScreen(android.support.v7.widget.RecyclerView, android.view.View, android.graphics.Rect, boolean))`(`[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)` parent, `[View](https://developer.android.com/reference/android/view/View.html)` child, `[Rect](https://developer.android.com/reference/android/graphics/Rect.html)` rect, boolean immediate) ` Called when a child of the RecyclerView wants a particular rectangle to be positioned onto the screen. |
| ` void` | ` `[requestLayout](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#requestLayout())`() ` Calls`RecyclerView#requestLayout`on the underlying RecyclerView |
| ` void` | ` `[requestSimpleAnimationsInNextLayout](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#requestSimpleAnimationsInNextLayout())`() ` A LayoutManager can call this method to force RecyclerView to run simple animations in the next layout pass, even if there is not any trigger to do so. |
| ` int` | ` `[scrollHorizontallyBy](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#scrollHorizontallyBy(int, android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))`(int dx, `[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state) ` Scroll horizontally by dx pixels in screen coordinates and return the distance traveled. |
| ` void` | ` `[scrollToPosition](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#scrollToPosition(int))`(int position) ` Scroll to the specified adapter position. |
| ` int` | ` `[scrollVerticallyBy](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#scrollVerticallyBy(int, android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))`(int dy, `[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)` recycler, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state) ` Scroll vertically by dy pixels in screen coordinates and return the distance traveled. |
| ` void` | ` `[setAutoMeasureEnabled](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setAutoMeasureEnabled(boolean))`(boolean enabled) ` *This method was deprecated in API level 27.1.0. Implementors of LayoutManager should define whether or not it uses AutoMeasure by overriding[isAutoMeasureEnabled()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isAutoMeasureEnabled()).* |
| ` final void` | ` `[setItemPrefetchEnabled](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setItemPrefetchEnabled(boolean))`(boolean enabled) ` Sets whether the LayoutManager should be queried for views outside of its viewport while the UI thread is idle between frames. |
| ` void` | ` `[setMeasuredDimension](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setMeasuredDimension(int, int))`(int widthSize, int heightSize) ` [Set the measured dimensions](https://developer.android.com/reference/android/view/View.html#setMeasuredDimension(int, int))of the host RecyclerView. |
| ` void` | ` `[setMeasuredDimension](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setMeasuredDimension(android.graphics.Rect, int, int))`(`[Rect](https://developer.android.com/reference/android/graphics/Rect.html)` childrenBounds, int wSpec, int hSpec) ` Sets the measured dimensions from the given bounding box of the children and the measurement specs that were passed into[onMeasure(int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#onMeasure(int, int)). |
| ` void` | ` `[setMeasurementCacheEnabled](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setMeasurementCacheEnabled(boolean))`(boolean measurementCacheEnabled) ` Sets whether RecyclerView should use its own measurement cache for the children. |
| ` void` | ` `[smoothScrollToPosition](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#smoothScrollToPosition(android.support.v7.widget.RecyclerView, android.support.v7.widget.RecyclerView.State, int))`(`[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)` recyclerView, `[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)` state, int position) `
Smooth scroll to the specified adapter position. |
| ` void` | ` `[startSmoothScroll](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#startSmoothScroll(android.support.v7.widget.RecyclerView.SmoothScroller))`(`[RecyclerView.SmoothScroller](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.SmoothScroller)` smoothScroller) `
Starts a smooth scroll using the provided SmoothScroller. |
| ` void` | ` `[stopIgnoringView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#stopIgnoringView(android.view.View))`(`[View](https://developer.android.com/reference/android/view/View.html)` view) ` View can be scrapped and recycled again. |
| ` boolean` | ` `[supportsPredictiveItemAnimations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#supportsPredictiveItemAnimations())`() ` Returns whether this LayoutManager supports "predictive item animations". |
| ### Inherited methods |
|-----------------------|---|
| [](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#)From class` java.lang.Object ` |-------------------|-------------------------------| | ` Object` | ` clone() ` | | ` boolean` | ` equals(Object arg0) ` | | ` void` | ` finalize() ` | | ` final Class` | ` getClass() ` | | ` int` | ` hashCode() ` | | ` final void` | ` notify() ` | | ` final void` | ` notifyAll() ` | | ` String` | ` toString() ` | | ` final void` | ` wait(long arg0, int arg1) ` | | ` final void` | ` wait(long arg0) ` | | ` final void` | ` wait() ` | ||
## XML attributes
### RecyclerView_android_orientation
**Related methods:**
- [getProperties(Context,AttributeSet,int,int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getProperties(android.content.Context, android.util.AttributeSet, int, int))
### RecyclerView_reverseLayout
**Related methods:**
- [getProperties(Context,AttributeSet,int,int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getProperties(android.content.Context, android.util.AttributeSet, int, int))
### RecyclerView_spanCount
**Related methods:**
- [getProperties(Context,AttributeSet,int,int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getProperties(android.content.Context, android.util.AttributeSet, int, int))
### RecyclerView_stackFromEnd
**Related methods:**
- [getProperties(Context,AttributeSet,int,int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getProperties(android.content.Context, android.util.AttributeSet, int, int))
## Public constructors
### RecyclerView.LayoutManager
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
RecyclerView.LayoutManager ()
```
## Public methods
### addDisappearingView
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void addDisappearingView (View child,
int index)
```
To be called only during[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))to add a view to the layout that is known to be going away, either because it has been[removed](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Adapter#notifyItemRemoved(int))or because it is actually not in the visible portion of the container but is being laid out in order to inform RecyclerView in how to animate the item out of view.
Views added via this method are going to be invisible to LayoutManager after the dispatchLayout pass is complete. They cannot be retrieved via[getChildAt(int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getChildAt(int))or won't be included in[getChildCount()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getChildCount())method.
| Parameters ||
|---------|------------------------------------------------------------|
| `child` | `View`: View to add and then remove with animation.
|
| `index` | `int`: Index of the view.
|
### addDisappearingView
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void addDisappearingView (View child)
```
To be called only during[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))to add a view to the layout that is known to be going away, either because it has been[removed](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Adapter#notifyItemRemoved(int))or because it is actually not in the visible portion of the container but is being laid out in order to inform RecyclerView in how to animate the item out of view.
Views added via this method are going to be invisible to LayoutManager after the dispatchLayout pass is complete. They cannot be retrieved via[getChildAt(int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getChildAt(int))or won't be included in[getChildCount()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getChildCount())method.
| Parameters ||
|---------|------------------------------------------------------------|
| `child` | `View`: View to add and then remove with animation.
|
### addView
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void addView (View child,
int index)
```
Add a view to the currently attached RecyclerView if needed. LayoutManagers should use this method to add views obtained from a[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)using[getViewForPosition(int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler#getViewForPosition(int)).
| Parameters ||
|---------|-------------------------------------|
| `child` | `View`: View to add
|
| `index` | `int`: Index to add child at
|
### addView
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void addView (View child)
```
Add a view to the currently attached RecyclerView if needed. LayoutManagers should use this method to add views obtained from a[RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)using[getViewForPosition(int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler#getViewForPosition(int)).
| Parameters ||
|---------|----------------------------|
| `child` | `View`: View to add
|
### assertInLayoutOrScroll
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void assertInLayoutOrScroll (String message)
```
Checks if RecyclerView is in the middle of a layout or scroll and throws an[IllegalStateException](https://developer.android.com/reference/java/lang/IllegalStateException)if it**is not**.
| Parameters ||
|-----------|--------------------------------------------------------------|
| `message` | `String`: The message for the exception. Can be null.
|
**See also:**
- [assertNotInLayoutOrScroll(String)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#assertNotInLayoutOrScroll(java.lang.String))
### assertNotInLayoutOrScroll
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void assertNotInLayoutOrScroll (String message)
```
Checks if RecyclerView is in the middle of a layout or scroll and throws an[IllegalStateException](https://developer.android.com/reference/java/lang/IllegalStateException)if it**is**.
| Parameters ||
|-----------|--------------------------------------------------------------|
| `message` | `String`: The message for the exception. Can be null.
|
**See also:**
- [assertInLayoutOrScroll(String)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#assertInLayoutOrScroll(java.lang.String))
### attachView
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void attachView (View child)
```
Reattach a previously[detached](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachView(android.view.View))view. This method should not be used to reattach views that were previously[detachAndScrapView(android.view.View, RecyclerView.Recycler)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachAndScrapView(android.view.View, android.support.v7.widget.RecyclerView.Recycler))scrapped}.
| Parameters ||
|---------|----------------------------------|
| `child` | `View`: Child to reattach
|
### attachView
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void attachView (View child,
int index)
```
Reattach a previously[detached](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachView(android.view.View))view. This method should not be used to reattach views that were previously[detachAndScrapView(android.view.View, RecyclerView.Recycler)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachAndScrapView(android.view.View, android.support.v7.widget.RecyclerView.Recycler))scrapped}.
| Parameters ||
|---------|----------------------------------------------|
| `child` | `View`: Child to reattach
|
| `index` | `int`: Intended child index for child
|
### attachView
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void attachView (View child,
int index,
RecyclerView.LayoutParams lp)
```
Reattach a previously[detached](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachView(android.view.View))view. This method should not be used to reattach views that were previously[detachAndScrapView(android.view.View, RecyclerView.Recycler)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachAndScrapView(android.view.View, android.support.v7.widget.RecyclerView.Recycler))scrapped}.
| Parameters ||
|---------|------------------------------------------------------------|
| `child` | `View`: Child to reattach
|
| `index` | `int`: Intended child index for child
|
| `lp` | `RecyclerView.LayoutParams`: LayoutParams for child
|
### calculateItemDecorationsForChild
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void calculateItemDecorationsForChild (View child,
Rect outRect)
```
Calculates the item decor insets applied to the given child and updates the provided Rect instance with the inset values.
- The Rect's left is set to the total width of left decorations.
- The Rect's top is set to the total height of top decorations.
- The Rect's right is set to the total width of right decorations.
- The Rect's bottom is set to total height of bottom decorations.
Note that item decorations are automatically calculated when one of the LayoutManager's measure child methods is called. If you need to measure the child with custom specs via[measure(int, int)](https://developer.android.com/reference/android/view/View.html#measure(int, int)), you can use this method to get decorations.
| Parameters ||
|-----------|----------------------------------------------------------------------|
| `child` | `View`: The child view whose decorations should be calculated
|
| `outRect` | `Rect`: The Rect to hold result values
|
### canScrollHorizontally
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean canScrollHorizontally ()
```
Query if horizontal scrolling is currently supported. The default implementation returns false.
| Returns ||
|-----------|--------------------------------------------------------------------------------|
| `boolean` | True if this LayoutManager can scroll the current contents horizontally
|
### canScrollVertically
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean canScrollVertically ()
```
Query if vertical scrolling is currently supported. The default implementation returns false.
| Returns ||
|-----------|------------------------------------------------------------------------------|
| `boolean` | True if this LayoutManager can scroll the current contents vertically
|
### checkLayoutParams
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean checkLayoutParams (RecyclerView.LayoutParams lp)
```
Determines the validity of the supplied LayoutParams object.
This should check to make sure that the object is of the correct type and all values are within acceptable ranges. The default implementation returns`true`for non-null params.
| Parameters ||
|------|------------------------------------------------------------------|
| `lp` | `RecyclerView.LayoutParams`: LayoutParams object to check
|
| Returns ||
|-----------|-------------------------------------------------------------------|
| `boolean` | true if this LayoutParams object is valid, false otherwise
|
### chooseSize
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int chooseSize (int spec,
int desired,
int min)
```
Chooses a size from the given specs and parameters that is closest to the desired size and also complies with the spec.
| Parameters ||
|-----------|-----------------------------------------|
| `spec` | `int`: The measureSpec
|
| `desired` | `int`: The preferred measurement
|
| `min` | `int`: The minimum value
|
| Returns ||
|-------|--------------------------------------------|
| `int` | A size that fits to the given specs
|
### collectAdjacentPrefetchPositions
added in[version 25.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void collectAdjacentPrefetchPositions (int dx,
int dy,
RecyclerView.State state,
RecyclerView.LayoutManager.LayoutPrefetchRegistry layoutPrefetchRegistry)
```
Gather all positions from the LayoutManager to be prefetched, given specified momentum.
If item prefetch is enabled, this method is called in between traversals to gather which positions the LayoutManager will soon need, given upcoming movement in subsequent traversals.
The LayoutManager should call[addPosition(int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager.LayoutPrefetchRegistry#addPosition(int, int))for each item to be prepared, and these positions will have their ViewHolders created and bound, if there is sufficient time available, in advance of being needed by a scroll or layout.
| Parameters ||
|--------------------------|------------------------------------------------------------------------------------------------------------|
| `dx` | `int`: X movement component.
|
| `dy` | `int`: Y movement component.
|
| `state` | `RecyclerView.State`: State of RecyclerView
|
| `layoutPrefetchRegistry` | `RecyclerView.LayoutManager.LayoutPrefetchRegistry`: PrefetchRegistry to add prefetch entries into.
|
**See also:**
- [isItemPrefetchEnabled()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isItemPrefetchEnabled())
- [collectInitialPrefetchPositions(int, LayoutPrefetchRegistry)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#collectInitialPrefetchPositions(int, android.support.v7.widget.RecyclerView.LayoutManager.LayoutPrefetchRegistry))
### collectInitialPrefetchPositions
added in[version 25.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void collectInitialPrefetchPositions (int adapterItemCount,
RecyclerView.LayoutManager.LayoutPrefetchRegistry layoutPrefetchRegistry)
```
Gather all positions from the LayoutManager to be prefetched in preperation for its RecyclerView to come on screen, due to the movement of another, containing RecyclerView.
This method is only called when a RecyclerView is nested in another RecyclerView.
If item prefetch is enabled for this LayoutManager, as well in another containing LayoutManager, this method is called in between draw traversals to gather which positions this LayoutManager will first need, once it appears on the screen.
For example, if this LayoutManager represents a horizontally scrolling list within a vertically scrolling LayoutManager, this method would be called when the horizontal list is about to come onscreen.
The LayoutManager should call[addPosition(int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager.LayoutPrefetchRegistry#addPosition(int, int))for each item to be prepared, and these positions will have their ViewHolders created and bound, if there is sufficient time available, in advance of being needed by a scroll or layout.
| Parameters ||
|--------------------------|------------------------------------------------------------------------------------------------------------|
| `adapterItemCount` | `int`: number of items in the associated adapter.
|
| `layoutPrefetchRegistry` | `RecyclerView.LayoutManager.LayoutPrefetchRegistry`: PrefetchRegistry to add prefetch entries into.
|
**See also:**
- [isItemPrefetchEnabled()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isItemPrefetchEnabled())
- [collectAdjacentPrefetchPositions(int, int, State, LayoutPrefetchRegistry)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#collectAdjacentPrefetchPositions(int, int, android.support.v7.widget.RecyclerView.State, android.support.v7.widget.RecyclerView.LayoutManager.LayoutPrefetchRegistry))
### computeHorizontalScrollExtent
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int computeHorizontalScrollExtent (RecyclerView.State state)
```
Override this method if you want to support scroll bars.
Read[computeHorizontalScrollExtent()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#computeHorizontalScrollExtent())for details.
Default implementation returns 0.
| Parameters ||
|---------|------------------------------------------------------------|
| `state` | `RecyclerView.State`: Current state of RecyclerView
|
| Returns ||
|-------|-------------------------------------------------------|
| `int` | The horizontal extent of the scrollbar's thumb
|
**See also:**
- [computeHorizontalScrollExtent()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#computeHorizontalScrollExtent())
### computeHorizontalScrollOffset
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int computeHorizontalScrollOffset (RecyclerView.State state)
```
Override this method if you want to support scroll bars.
Read[computeHorizontalScrollOffset()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#computeHorizontalScrollOffset())for details.
Default implementation returns 0.
| Parameters ||
|---------|------------------------------------------------------------------------------------------------|
| `state` | `RecyclerView.State`: Current State of RecyclerView where you can find total item count
|
| Returns ||
|-------|-------------------------------------------------------|
| `int` | The horizontal offset of the scrollbar's thumb
|
**See also:**
- [computeHorizontalScrollOffset()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#computeHorizontalScrollOffset())
### computeHorizontalScrollRange
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int computeHorizontalScrollRange (RecyclerView.State state)
```
Override this method if you want to support scroll bars.
Read[computeHorizontalScrollRange()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#computeHorizontalScrollRange())for details.
Default implementation returns 0.
| Parameters ||
|---------|------------------------------------------------------------------------------------------------|
| `state` | `RecyclerView.State`: Current State of RecyclerView where you can find total item count
|
| Returns ||
|-------|-------------------------------------------------------------------------|
| `int` | The total horizontal range represented by the vertical scrollbar
|
**See also:**
- [computeHorizontalScrollRange()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#computeHorizontalScrollRange())
### computeVerticalScrollExtent
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int computeVerticalScrollExtent (RecyclerView.State state)
```
Override this method if you want to support scroll bars.
Read[computeVerticalScrollExtent()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#computeVerticalScrollExtent())for details.
Default implementation returns 0.
| Parameters ||
|---------|------------------------------------------------------------|
| `state` | `RecyclerView.State`: Current state of RecyclerView
|
| Returns ||
|-------|-----------------------------------------------------|
| `int` | The vertical extent of the scrollbar's thumb
|
**See also:**
- [computeVerticalScrollExtent()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#computeVerticalScrollExtent())
### computeVerticalScrollOffset
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int computeVerticalScrollOffset (RecyclerView.State state)
```
Override this method if you want to support scroll bars.
Read[computeVerticalScrollOffset()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#computeVerticalScrollOffset())for details.
Default implementation returns 0.
| Parameters ||
|---------|------------------------------------------------------------------------------------------------|
| `state` | `RecyclerView.State`: Current State of RecyclerView where you can find total item count
|
| Returns ||
|-------|-----------------------------------------------------|
| `int` | The vertical offset of the scrollbar's thumb
|
**See also:**
- [computeVerticalScrollOffset()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#computeVerticalScrollOffset())
### computeVerticalScrollRange
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int computeVerticalScrollRange (RecyclerView.State state)
```
Override this method if you want to support scroll bars.
Read[computeVerticalScrollRange()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#computeVerticalScrollRange())for details.
Default implementation returns 0.
| Parameters ||
|---------|------------------------------------------------------------------------------------------------|
| `state` | `RecyclerView.State`: Current State of RecyclerView where you can find total item count
|
| Returns ||
|-------|-----------------------------------------------------------------------|
| `int` | The total vertical range represented by the vertical scrollbar
|
**See also:**
- [computeVerticalScrollRange()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#computeVerticalScrollRange())
### detachAndScrapAttachedViews
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void detachAndScrapAttachedViews (RecyclerView.Recycler recycler)
```
Temporarily detach and scrap all currently attached child views. Views will be scrapped into the given Recycler. The Recycler may prefer to reuse scrap views before other views that were previously recycled.
| Parameters ||
|------------|--------------------------------------------------------------|
| `recycler` | `RecyclerView.Recycler`: Recycler to scrap views into
|
### detachAndScrapView
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void detachAndScrapView (View child,
RecyclerView.Recycler recycler)
```
Detach a child view and add it to a[Recycler's](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)scrap heap.
Scrapping a view allows it to be rebound and reused to show updated or different data.
| Parameters ||
|------------|-----------------------------------------------------------------------------|
| `child` | `View`: Child to detach and scrap
|
| `recycler` | `RecyclerView.Recycler`: Recycler to deposit the new scrap view into
|
### detachAndScrapViewAt
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void detachAndScrapViewAt (int index,
RecyclerView.Recycler recycler)
```
Detach a child view and add it to a[Recycler's](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)scrap heap.
Scrapping a view allows it to be rebound and reused to show updated or different data.
| Parameters ||
|------------|-----------------------------------------------------------------------------|
| `index` | `int`: Index of child to detach and scrap
|
| `recycler` | `RecyclerView.Recycler`: Recycler to deposit the new scrap view into
|
### detachView
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void detachView (View child)
```
Temporarily detach a child view.
LayoutManagers may want to perform a lightweight detach operation to rearrange views currently attached to the RecyclerView. Generally LayoutManager implementations will want to use[detachAndScrapView(android.view.View, RecyclerView.Recycler)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachAndScrapView(android.view.View, android.support.v7.widget.RecyclerView.Recycler))so that the detached view may be rebound and reused.
If a LayoutManager uses this method to detach a view, it*must* [reattach](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#attachView(android.view.View, int, android.support.v7.widget.RecyclerView.LayoutParams))or[fully remove](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#removeDetachedView(android.view.View))the detached view before the LayoutManager entry point method called by RecyclerView returns.
| Parameters ||
|---------|--------------------------------|
| `child` | `View`: Child to detach
|
### detachViewAt
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void detachViewAt (int index)
```
Temporarily detach a child view.
LayoutManagers may want to perform a lightweight detach operation to rearrange views currently attached to the RecyclerView. Generally LayoutManager implementations will want to use[detachAndScrapView(android.view.View, RecyclerView.Recycler)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachAndScrapView(android.view.View, android.support.v7.widget.RecyclerView.Recycler))so that the detached view may be rebound and reused.
If a LayoutManager uses this method to detach a view, it*must* [reattach](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#attachView(android.view.View, int, android.support.v7.widget.RecyclerView.LayoutParams))or[fully remove](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#removeDetachedView(android.view.View))the detached view before the LayoutManager entry point method called by RecyclerView returns.
| Parameters ||
|---------|--------------------------------------------|
| `index` | `int`: Index of the child to detach
|
### endAnimation
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void endAnimation (View view)
```
Ends all animations on the view created by the[RecyclerView.ItemAnimator](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemAnimator).
| Parameters ||
|--------|-------------------------------------------------------------------|
| `view` | `View`: The View for which the animations should be ended.
|
**See also:**
- [endAnimations()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemAnimator#endAnimations())
### findContainingItemView
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
View findContainingItemView (View view)
```
Traverses the ancestors of the given view and returns the item view that contains it and also a direct child of the LayoutManager.
Note that this method may return null if the view is a child of the RecyclerView but not a child of the LayoutManager (e.g. running a disappear animation).
| Parameters ||
|--------|--------------------------------------------------------------------|
| `view` | `View`: The view that is a descendant of the LayoutManager.
|
| Returns ||
|------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------|
| [View](https://developer.android.com/reference/android/view/View.html) | The direct child of the LayoutManager which contains the given view or null if the provided view is not a descendant of this LayoutManager.
|
**See also:**
- [getChildViewHolder(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#getChildViewHolder(android.view.View))
- [findContainingViewHolder(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#findContainingViewHolder(android.view.View))
### findViewByPosition
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
View findViewByPosition (int position)
```
Finds the view which represents the given adapter position.
This method traverses each child since it has no information about child order. Override this method to improve performance if your LayoutManager keeps data about child views.
If a view is ignored via[ignoreView(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#ignoreView(android.view.View)), it is also ignored by this method.
| Parameters ||
|------------|-----------------------------------------------|
| `position` | `int`: Position of the item in adapter
|
| Returns ||
|------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------|
| [View](https://developer.android.com/reference/android/view/View.html) | The child view that represents the given position or null if the position is not laid out
|
### generateDefaultLayoutParams
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
RecyclerView.LayoutParams generateDefaultLayoutParams ()
```
Create a default`LayoutParams`object for a child of the RecyclerView.
LayoutManagers will often want to use a custom`LayoutParams`type to store extra information specific to the layout. Client code should subclass[RecyclerView.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutParams)for this purpose.
*Important:* if you use your own custom`LayoutParams`type you must also override[checkLayoutParams(LayoutParams)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#checkLayoutParams(android.support.v7.widget.RecyclerView.LayoutParams)),[generateLayoutParams(android.view.ViewGroup.LayoutParams)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#generateLayoutParams(android.view.ViewGroup.LayoutParams))and[generateLayoutParams(android.content.Context, android.util.AttributeSet)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#generateLayoutParams(android.content.Context, android.util.AttributeSet)).
| Returns ||
|--------------------------------------------------------------------------------------------------------------------------|--------------------------------------------|
| [RecyclerView.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutParams) | A new LayoutParams for a child view
|
### generateLayoutParams
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
RecyclerView.LayoutParams generateLayoutParams (Context c,
AttributeSet attrs)
```
Create a LayoutParams object suitable for this LayoutManager from an inflated layout resource.
*Important:* if you use your own custom`LayoutParams`type you must also override[checkLayoutParams(LayoutParams)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#checkLayoutParams(android.support.v7.widget.RecyclerView.LayoutParams)),[generateLayoutParams(android.view.ViewGroup.LayoutParams)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#generateLayoutParams(android.view.ViewGroup.LayoutParams))and[generateLayoutParams(android.content.Context, android.util.AttributeSet)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#generateLayoutParams(android.content.Context, android.util.AttributeSet)).
| Parameters ||
|---------|-----------------------------------------------------------------------|
| `c` | `Context`: Context for obtaining styled attributes
|
| `attrs` | `AttributeSet`: AttributeSet describing the supplied arguments
|
| Returns ||
|--------------------------------------------------------------------------------------------------------------------------|----------------------------------|
| [RecyclerView.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutParams) | a new LayoutParams object
|
### generateLayoutParams
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
RecyclerView.LayoutParams generateLayoutParams (ViewGroup.LayoutParams lp)
```
Create a LayoutParams object suitable for this LayoutManager, copying relevant values from the supplied LayoutParams object if possible.
*Important:* if you use your own custom`LayoutParams`type you must also override[checkLayoutParams(LayoutParams)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#checkLayoutParams(android.support.v7.widget.RecyclerView.LayoutParams)),[generateLayoutParams(android.view.ViewGroup.LayoutParams)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#generateLayoutParams(android.view.ViewGroup.LayoutParams))and[generateLayoutParams(android.content.Context, android.util.AttributeSet)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#generateLayoutParams(android.content.Context, android.util.AttributeSet)).
| Parameters ||
|------|---------------------------------------------------------------------------------|
| `lp` | `ViewGroup.LayoutParams`: Source LayoutParams object to copy values from
|
| Returns ||
|--------------------------------------------------------------------------------------------------------------------------|----------------------------------|
| [RecyclerView.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutParams) | a new LayoutParams object
|
### getBaseline
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getBaseline ()
```
Returns offset of the RecyclerView's text baseline from the its top boundary.
| Returns ||
|-------|--------------------------------------------------------------------------------------------------------------|
| `int` | The offset of the RecyclerView's text baseline from the its top boundary; -1 if there is no baseline.
|
### getBottomDecorationHeight
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getBottomDecorationHeight (View child)
```
Returns the total height of item decorations applied to child's bottom.
Note that this value is not updated until the View is measured or[calculateItemDecorationsForChild(View, Rect)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#calculateItemDecorationsForChild(android.view.View, android.graphics.Rect))is called.
| Parameters ||
|---------|-------------------------------|
| `child` | `View`: Child to query
|
| Returns ||
|-------|----------------------------------------------------------------------------|
| `int` | The total height of item decorations applied to the child's bottom.
|
**See also:**
- [getDecoratedBottom(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedBottom(android.view.View))
- [calculateItemDecorationsForChild(View, Rect)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#calculateItemDecorationsForChild(android.view.View, android.graphics.Rect))
### getChildAt
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
View getChildAt (int index)
```
Return the child view at the given index
| Parameters ||
|---------|----------------------------------------|
| `index` | `int`: Index of child to return
|
| Returns ||
|------------------------------------------------------------------------|----------------------------|
| [View](https://developer.android.com/reference/android/view/View.html) | Child view at index
|
### getChildCount
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getChildCount ()
```
Return the current number of child views attached to the parent RecyclerView. This does not include child views that were temporarily detached and/or scrapped.
| Returns ||
|-------|------------------------------------|
| `int` | Number of attached children
|
### getChildMeasureSpec
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getChildMeasureSpec (int parentSize,
int parentMode,
int padding,
int childDimension,
boolean canScroll)
```
Calculate a MeasureSpec value for measuring a child view in one dimension.
| Parameters ||
|------------------|-----------------------------------------------------------------------------------------------------------------------------------|
| `parentSize` | `int`: Size of the parent view where the child will be placed
|
| `parentMode` | `int`: The measurement spec mode of the parent
|
| `padding` | `int`: Total space currently consumed by other elements of parent
|
| `childDimension` | `int`: Desired size of the child view, or MATCH_PARENT/WRAP_CONTENT. Generally obtained from the child view's LayoutParams
|
| `canScroll` | `boolean`: true if the parent RecyclerView can scroll in this dimension
|
| Returns ||
|-------|-----------------------------------------------|
| `int` | a MeasureSpec value for the child view
|
### getChildMeasureSpec
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getChildMeasureSpec (int parentSize,
int padding,
int childDimension,
boolean canScroll)
```
**This method was deprecated in API level 24.1.0.**
use[getChildMeasureSpec(int, int, int, int, boolean)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getChildMeasureSpec(int, int, int, int, boolean))
Calculate a MeasureSpec value for measuring a child view in one dimension.
| Parameters ||
|------------------|-----------------------------------------------------------------------------------------------------------------------------------|
| `parentSize` | `int`: Size of the parent view where the child will be placed
|
| `padding` | `int`: Total space currently consumed by other elements of the parent
|
| `childDimension` | `int`: Desired size of the child view, or MATCH_PARENT/WRAP_CONTENT. Generally obtained from the child view's LayoutParams
|
| `canScroll` | `boolean`: true if the parent RecyclerView can scroll in this dimension
|
| Returns ||
|-------|-----------------------------------------------|
| `int` | a MeasureSpec value for the child view
|
### getClipToPadding
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean getClipToPadding ()
```
Check if the RecyclerView is configured to clip child views to its padding.
| Returns ||
|-----------|---------------------------------------------------------------------------------|
| `boolean` | true if this RecyclerView clips children to its padding, false otherwise
|
### getColumnCountForAccessibility
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getColumnCountForAccessibility (RecyclerView.Recycler recycler,
RecyclerView.State state)
```
Returns the number of columns for accessibility.
Default implementation returns the number of items in the adapter if LayoutManager supports horizontal scrolling or 1 if LayoutManager does not support horizontal scrolling.
| Parameters ||
|------------|----------------------------------------------------------------------------------------------------------------|
| `recycler` | `RecyclerView.Recycler`: The Recycler that can be used to convert view positions into adapter positions
|
| `state` | `RecyclerView.State`: The current state of RecyclerView
|
| Returns ||
|-------|---------------------------------------------------------------|
| `int` | The number of rows in LayoutManager for accessibility.
|
### getDecoratedBottom
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getDecoratedBottom (View child)
```
Returns the bottom edge of the given child view within its parent, offset by any applied[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration).
| Parameters ||
|---------|-------------------------------|
| `child` | `View`: Child to query
|
| Returns ||
|-------|-----------------------------------------------|
| `int` | Child bottom edge with offsets applied
|
**See also:**
- [getBottomDecorationHeight(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getBottomDecorationHeight(android.view.View))
### getDecoratedBoundsWithMargins
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void getDecoratedBoundsWithMargins (View view,
Rect outBounds)
```
Returns the bounds of the view including its decoration and margins.
| Parameters ||
|-------------|---------------------------------------------------------------------------------------------------------|
| `view` | `View`: The view element to check
|
| `outBounds` | `Rect`: A rect that will receive the bounds of the element including its decoration and margins.
|
### getDecoratedLeft
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getDecoratedLeft (View child)
```
Returns the left edge of the given child view within its parent, offset by any applied[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration).
| Parameters ||
|---------|-------------------------------|
| `child` | `View`: Child to query
|
| Returns ||
|-------|---------------------------------------------|
| `int` | Child left edge with offsets applied
|
**See also:**
- [getLeftDecorationWidth(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getLeftDecorationWidth(android.view.View))
### getDecoratedMeasuredHeight
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getDecoratedMeasuredHeight (View child)
```
Returns the measured height of the given child, plus the additional size of any insets applied by[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration).
| Parameters ||
|---------|------------------------------------|
| `child` | `View`: Child view to query
|
| Returns ||
|-------|-----------------------------------------------------------|
| `int` | child's measured height plus`ItemDecoration`insets
|
**See also:**
- [getMeasuredHeight()](https://developer.android.com/https://developer.android.com/reference/android/view/View#getMeasuredHeight())
### getDecoratedMeasuredWidth
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getDecoratedMeasuredWidth (View child)
```
Returns the measured width of the given child, plus the additional size of any insets applied by[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration).
| Parameters ||
|---------|------------------------------------|
| `child` | `View`: Child view to query
|
| Returns ||
|-------|----------------------------------------------------------|
| `int` | child's measured width plus`ItemDecoration`insets
|
**See also:**
- [getMeasuredWidth()](https://developer.android.com/https://developer.android.com/reference/android/view/View#getMeasuredWidth())
### getDecoratedRight
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getDecoratedRight (View child)
```
Returns the right edge of the given child view within its parent, offset by any applied[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration).
| Parameters ||
|---------|-------------------------------|
| `child` | `View`: Child to query
|
| Returns ||
|-------|----------------------------------------------|
| `int` | Child right edge with offsets applied
|
**See also:**
- [getRightDecorationWidth(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getRightDecorationWidth(android.view.View))
### getDecoratedTop
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getDecoratedTop (View child)
```
Returns the top edge of the given child view within its parent, offset by any applied[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration).
| Parameters ||
|---------|-------------------------------|
| `child` | `View`: Child to query
|
| Returns ||
|-------|--------------------------------------------|
| `int` | Child top edge with offsets applied
|
**See also:**
- [getTopDecorationHeight(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getTopDecorationHeight(android.view.View))
### getFocusedChild
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
View getFocusedChild ()
```
Returns the item View which has or contains focus.
| Returns ||
|------------------------------------------------------------------------|--------------------------------------------------------------------------------------|
| [View](https://developer.android.com/reference/android/view/View.html) | A direct child of RecyclerView which has focus or contains the focused child.
|
### getHeight
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getHeight ()
```
Returns the height that is currently relevant to the LayoutManager.
This value is usually equal to the laid out height of the[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)but may reflect the current[View.MeasureSpec](https://developer.android.com/reference/android/view/View.MeasureSpec.html)height if the[RecyclerView.LayoutManager](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager)is using AutoMeasure and the RecyclerView is in the process of measuring. The LayoutManager must always use this method to retrieve the height relevant to it at any given time.
| Returns ||
|-------|-------------------------|
| `int` | Height in pixels
|
### getHeightMode
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getHeightMode ()
```
Return the height measurement spec mode that is currently relevant to the LayoutManager.
This value is set only if the LayoutManager opts into the AutoMeasure api via[setAutoMeasureEnabled(boolean)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setAutoMeasureEnabled(boolean)).
When RecyclerView is running a layout, this value is always set to[EXACTLY](https://developer.android.com/reference/android/view/View.MeasureSpec.html#EXACTLY)even if it was measured with a different spec mode.
| Returns ||
|-------|---------------------------------|
| `int` | Height measure spec mode
|
**See also:**
- [getMode(int)](https://developer.android.com/https://developer.android.com/reference/android/view/View.MeasureSpec#getMode(int))
### getItemCount
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getItemCount ()
```
Returns the number of items in the adapter bound to the parent RecyclerView.
Note that this number is not necessarily equal to[State#getItemCount()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State#getItemCount()). In methods where[RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)is available, you should use[State#getItemCount()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State#getItemCount())instead. For more details, check the documentation for[State#getItemCount()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State#getItemCount()).
| Returns ||
|-------|-------------------------------------------------|
| `int` | The number of items in the bound adapter
|
**See also:**
- [getItemCount()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State#getItemCount())
### getItemViewType
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getItemViewType (View view)
```
Returns the View type defined by the adapter.
| Parameters ||
|--------|----------------------------------|
| `view` | `View`: The view to query
|
| Returns ||
|-------|------------------------------------------------------|
| `int` | The type of the view assigned by the adapter.
|
### getLayoutDirection
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getLayoutDirection ()
```
Returns the resolved layout direction for this RecyclerView.
| Returns ||
|-------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `int` | [LAYOUT_DIRECTION_RTL](https://developer.android.com/reference/android/support/v4/view/ViewCompat#LAYOUT_DIRECTION_RTL)if the layout direction is RTL or returns[LAYOUT_DIRECTION_LTR](https://developer.android.com/reference/android/support/v4/view/ViewCompat#LAYOUT_DIRECTION_LTR)if the layout direction is not RTL.
|
### getLeftDecorationWidth
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getLeftDecorationWidth (View child)
```
Returns the total width of item decorations applied to child's left.
Note that this value is not updated until the View is measured or[calculateItemDecorationsForChild(View, Rect)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#calculateItemDecorationsForChild(android.view.View, android.graphics.Rect))is called.
| Parameters ||
|---------|-------------------------------|
| `child` | `View`: Child to query
|
| Returns ||
|-------|-------------------------------------------------------------------------|
| `int` | The total width of item decorations applied to the child's left.
|
**See also:**
- [getDecoratedLeft(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedLeft(android.view.View))
- [calculateItemDecorationsForChild(View, Rect)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#calculateItemDecorationsForChild(android.view.View, android.graphics.Rect))
### getMinimumHeight
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getMinimumHeight ()
```
| Returns ||
|-------|---------------------------------------------------------------------------------------------------------------------------------------|
| `int` | The host RecyclerView's[getMinimumHeight()](https://developer.android.com/reference/android/view/View.html#getMinimumHeight())
|
### getMinimumWidth
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getMinimumWidth ()
```
| Returns ||
|-------|-------------------------------------------------------------------------------------------------------------------------------------|
| `int` | The host RecyclerView's[getMinimumWidth()](https://developer.android.com/reference/android/view/View.html#getMinimumWidth())
|
### getPaddingBottom
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getPaddingBottom ()
```
Return the bottom padding of the parent RecyclerView
| Returns ||
|-------|--------------------------|
| `int` | Padding in pixels
|
### getPaddingEnd
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getPaddingEnd ()
```
Return the end padding of the parent RecyclerView
| Returns ||
|-------|--------------------------|
| `int` | Padding in pixels
|
### getPaddingLeft
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getPaddingLeft ()
```
Return the left padding of the parent RecyclerView
| Returns ||
|-------|--------------------------|
| `int` | Padding in pixels
|
### getPaddingRight
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getPaddingRight ()
```
Return the right padding of the parent RecyclerView
| Returns ||
|-------|--------------------------|
| `int` | Padding in pixels
|
### getPaddingStart
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getPaddingStart ()
```
Return the start padding of the parent RecyclerView
| Returns ||
|-------|--------------------------|
| `int` | Padding in pixels
|
### getPaddingTop
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getPaddingTop ()
```
Return the top padding of the parent RecyclerView
| Returns ||
|-------|--------------------------|
| `int` | Padding in pixels
|
### getPosition
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getPosition (View view)
```
Returns the adapter position of the item represented by the given View. This does not contain any adapter changes that might have happened after the last layout.
| Parameters ||
|--------|----------------------------------|
| `view` | `View`: The view to query
|
| Returns ||
|-------|-------------------------------------------------------------------------|
| `int` | The adapter position of the item which is rendered by this View.
|
### getProperties
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
RecyclerView.LayoutManager.Properties getProperties (Context context,
AttributeSet attrs,
int defStyleAttr,
int defStyleRes)
```
Parse the xml attributes to get the most common properties used by layout managers.
**Related XML Attributes:**
- [RecyclerView_android_orientation](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#attr_RecyclerView_android_orientation)
- [RecyclerView_spanCount](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#attr_RecyclerView_spanCount)
- [RecyclerView_reverseLayout](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#attr_RecyclerView_reverseLayout)
- [RecyclerView_stackFromEnd](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#attr_RecyclerView_stackFromEnd)
| Parameters ||
|----------------|-----------------------|
| `context` | `Context`
|
| `attrs` | `AttributeSet`
|
| `defStyleAttr` | `int`
|
| `defStyleRes` | `int`
|
| Returns ||
|--------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------|
| [RecyclerView.LayoutManager.Properties](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager.Properties) | an object containing the properties as specified in the attrs.
|
### getRightDecorationWidth
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getRightDecorationWidth (View child)
```
Returns the total width of item decorations applied to child's right.
Note that this value is not updated until the View is measured or[calculateItemDecorationsForChild(View, Rect)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#calculateItemDecorationsForChild(android.view.View, android.graphics.Rect))is called.
| Parameters ||
|---------|-------------------------------|
| `child` | `View`: Child to query
|
| Returns ||
|-------|--------------------------------------------------------------------------|
| `int` | The total width of item decorations applied to the child's right.
|
**See also:**
- [getDecoratedRight(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedRight(android.view.View))
- [calculateItemDecorationsForChild(View, Rect)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#calculateItemDecorationsForChild(android.view.View, android.graphics.Rect))
### getRowCountForAccessibility
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getRowCountForAccessibility (RecyclerView.Recycler recycler,
RecyclerView.State state)
```
Returns the number of rows for accessibility.
Default implementation returns the number of items in the adapter if LayoutManager supports vertical scrolling or 1 if LayoutManager does not support vertical scrolling.
| Parameters ||
|------------|----------------------------------------------------------------------------------------------------------------|
| `recycler` | `RecyclerView.Recycler`: The Recycler that can be used to convert view positions into adapter positions
|
| `state` | `RecyclerView.State`: The current state of RecyclerView
|
| Returns ||
|-------|---------------------------------------------------------------|
| `int` | The number of rows in LayoutManager for accessibility.
|
### getSelectionModeForAccessibility
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getSelectionModeForAccessibility (RecyclerView.Recycler recycler,
RecyclerView.State state)
```
Returns the selection mode for accessibility. Should be[SELECTION_MODE_NONE](https://developer.android.com/reference/android/support/v4/view/accessibility/AccessibilityNodeInfoCompat.CollectionInfoCompat#SELECTION_MODE_NONE),[SELECTION_MODE_SINGLE](https://developer.android.com/reference/android/support/v4/view/accessibility/AccessibilityNodeInfoCompat.CollectionInfoCompat#SELECTION_MODE_SINGLE)or[SELECTION_MODE_MULTIPLE](https://developer.android.com/reference/android/support/v4/view/accessibility/AccessibilityNodeInfoCompat.CollectionInfoCompat#SELECTION_MODE_MULTIPLE).
Default implementation returns[SELECTION_MODE_NONE](https://developer.android.com/reference/android/support/v4/view/accessibility/AccessibilityNodeInfoCompat.CollectionInfoCompat#SELECTION_MODE_NONE).
| Parameters ||
|------------|----------------------------------------------------------------------------------------------------------------|
| `recycler` | `RecyclerView.Recycler`: The Recycler that can be used to convert view positions into adapter positions
|
| `state` | `RecyclerView.State`: The current state of RecyclerView
|
| Returns ||
|-------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `int` | Selection mode for accessibility. Default implementation returns[SELECTION_MODE_NONE](https://developer.android.com/reference/android/support/v4/view/accessibility/AccessibilityNodeInfoCompat.CollectionInfoCompat#SELECTION_MODE_NONE).
|
### getTopDecorationHeight
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getTopDecorationHeight (View child)
```
Returns the total height of item decorations applied to child's top.
Note that this value is not updated until the View is measured or[calculateItemDecorationsForChild(View, Rect)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#calculateItemDecorationsForChild(android.view.View, android.graphics.Rect))is called.
| Parameters ||
|---------|-------------------------------|
| `child` | `View`: Child to query
|
| Returns ||
|-------|-------------------------------------------------------------------------|
| `int` | The total height of item decorations applied to the child's top.
|
**See also:**
- [getDecoratedTop(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedTop(android.view.View))
- [calculateItemDecorationsForChild(View, Rect)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#calculateItemDecorationsForChild(android.view.View, android.graphics.Rect))
### getTransformedBoundingBox
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void getTransformedBoundingBox (View child,
boolean includeDecorInsets,
Rect out)
```
Calculates the bounding box of the View while taking into account its matrix changes (translation, scale etc) with respect to the RecyclerView.
If`includeDecorInsets`is`true`, they are applied first before applying the View's matrix so that the decor offsets also go through the same transformation.
| Parameters ||
|----------------------|-----------------------------------------------------------------------------------|
| `child` | `View`: The ItemView whose bounding box should be calculated.
|
| `includeDecorInsets` | `boolean`: True if the decor insets should be included in the bounding box
|
| `out` | `Rect`: The rectangle into which the output will be written.
|
### getWidth
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getWidth ()
```
Returns the width that is currently relevant to the LayoutManager.
This value is usually equal to the laid out width of the[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)but may reflect the current[View.MeasureSpec](https://developer.android.com/reference/android/view/View.MeasureSpec.html)width if the[RecyclerView.LayoutManager](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager)is using AutoMeasure and the RecyclerView is in the process of measuring. The LayoutManager must always use this method to retrieve the width relevant to it at any given time.
| Returns ||
|-------|------------------------|
| `int` | Width in pixels
|
### getWidthMode
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int getWidthMode ()
```
Return the width measurement spec mode that is currently relevant to the LayoutManager.
This value is set only if the LayoutManager opts into the AutoMeasure api via[setAutoMeasureEnabled(boolean)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setAutoMeasureEnabled(boolean)).
When RecyclerView is running a layout, this value is always set to[EXACTLY](https://developer.android.com/reference/android/view/View.MeasureSpec.html#EXACTLY)even if it was measured with a different spec mode.
| Returns ||
|-------|--------------------------------|
| `int` | Width measure spec mode
|
**See also:**
- [getMode(int)](https://developer.android.com/https://developer.android.com/reference/android/view/View.MeasureSpec#getMode(int))
### hasFocus
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean hasFocus ()
```
Returns true if the RecyclerView this LayoutManager is bound to has or contains focus.
| Returns ||
|-----------|-------------------------------------------------------|
| `boolean` | true if the RecyclerView has or contains focus
|
**See also:**
- [hasFocus()](https://developer.android.com/https://developer.android.com/reference/android/view/View#hasFocus())
### ignoreView
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void ignoreView (View view)
```
Flags a view so that it will not be scrapped or recycled.
Scope of ignoring a child is strictly restricted to position tracking, scrapping and recyling. Methods like[removeAndRecycleAllViews(Recycler)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#removeAndRecycleAllViews(android.support.v7.widget.RecyclerView.Recycler))will ignore the child whereas[removeAllViews()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#removeAllViews())or[offsetChildrenHorizontal(int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#offsetChildrenHorizontal(int))will not ignore the child.
Before this child can be recycled again, you have to call[stopIgnoringView(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#stopIgnoringView(android.view.View)).
You can call this method only if your LayoutManger is in onLayout or onScroll callback.
| Parameters ||
|--------|--------------------------------|
| `view` | `View`: View to ignore.
|
**See also:**
- [stopIgnoringView(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#stopIgnoringView(android.view.View))
### isAttachedToWindow
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean isAttachedToWindow ()
```
Returns whether LayoutManager is currently attached to a RecyclerView which is attached to a window.
| Returns ||
|-----------|-------------------------------------------------------------------------------------------------------------|
| `boolean` | True if this LayoutManager is controlling a RecyclerView and the RecyclerView is attached to window.
|
### isAutoMeasureEnabled
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean isAutoMeasureEnabled ()
```
Returns whether the measuring pass of layout should use the AutoMeasure mechanism of[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)or if it should be done by the LayoutManager's implementation of[onMeasure(Recycler, State, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onMeasure(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State, int, int)).
This method returns false by default (it actually returns the value passed to the deprecated[setAutoMeasureEnabled(boolean)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setAutoMeasureEnabled(boolean))) and should be overridden to return true if a LayoutManager wants to be auto measured by the RecyclerView.
If this method is overridden to return true,[onMeasure(Recycler, State, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onMeasure(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State, int, int))should not be overridden.
AutoMeasure is a RecyclerView mechanism that handles the measuring pass of layout in a simple and contract satisfying way, including the wrapping of children laid out by LayoutManager. Simply put, it handles wrapping children by calling[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))during a call to[onMeasure(int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#onMeasure(int, int)), and then calculating desired dimensions based on children's dimensions and positions. It does this while supporting all existing animation capabilities of the RecyclerView.
More specifically:
1. When[onMeasure(int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#onMeasure(int, int))is called, if the provided measure specs both have a mode of[EXACTLY](https://developer.android.com/reference/android/view/View.MeasureSpec.html#EXACTLY), RecyclerView will set its measured dimensions accordingly and return, allowing layout to continue as normal (Actually, RecyclerView will call[onMeasure(Recycler, State, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onMeasure(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State, int, int))for backwards compatibility reasons but it should not be overridden if AutoMeasure is being used).
2. If one of the layout specs is not`EXACT`, the RecyclerView will start the layout process. It will first process all pending Adapter updates and then decide whether to run a predictive layout. If it decides to do so, it will first call[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))with[isPreLayout()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State#isPreLayout())set to`true`. At this stage,[getWidth()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getWidth())and[getHeight()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getHeight())will still return the width and height of the RecyclerView as of the last layout calculation.
After handling the predictive case, RecyclerView will call[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))with[isMeasuring()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State#isMeasuring())set to`true`and[isPreLayout()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State#isPreLayout())set to`false`. The LayoutManager can access the measurement specs via[getHeight()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getHeight()),[getHeightMode()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getHeightMode()),[getWidth()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getWidth())and[getWidthMode()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getWidthMode()).
3. After the layout calculation, RecyclerView sets the measured width \& height by calculating the bounding box for the children (+ RecyclerView's padding). The LayoutManagers can override[setMeasuredDimension(Rect, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setMeasuredDimension(android.graphics.Rect, int, int))to choose different values. For instance, GridLayoutManager overrides this value to handle the case where if it is vertical and has 3 columns but only 2 items, it should still measure its width to fit 3 items, not 2.
4. Any following calls to[onMeasure(int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#onMeasure(int, int))will run[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))with[isMeasuring()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State#isMeasuring())set to`true`and[isPreLayout()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State#isPreLayout())set to`false`. RecyclerView will take care of which views are actually added / removed / moved / changed for animations so that the LayoutManager should not worry about them and handle each[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))call as if it is the last one.
5. When measure is complete and RecyclerView's[onLayout(boolean, int, int, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#onLayout(boolean, int, int, int, int))method is called, RecyclerView checks whether it already did layout calculations during the measure pass and if so, it re-uses that information. It may still decide to call[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))if the last measure spec was different from the final dimensions or adapter contents have changed between the measure call and the layout call.
6. Finally, animations are calculated and run as usual.
| Returns ||
|-----------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `boolean` | `True`if the measuring pass of layout should use the AutoMeasure mechanism of[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)or`False`if it should be done by the LayoutManager's implementation of[onMeasure(Recycler, State, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onMeasure(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State, int, int)).
|
**See also:**
- [setMeasuredDimension(Rect, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setMeasuredDimension(android.graphics.Rect, int, int))
- [onMeasure(Recycler, State, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onMeasure(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State, int, int))
### isFocused
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean isFocused ()
```
Returns true if the RecyclerView this LayoutManager is bound to has focus.
| Returns ||
|-----------|-------------------------------------------------------------|
| `boolean` | True if the RecyclerView has focus, false otherwise.
|
**See also:**
- [isFocused()](https://developer.android.com/https://developer.android.com/reference/android/view/View#isFocused())
### isItemPrefetchEnabled
added in[version 25.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean isItemPrefetchEnabled ()
```
Sets whether the LayoutManager should be queried for views outside of its viewport while the UI thread is idle between frames.
| Returns ||
|-----------|----------------------------------------------------------|
| `boolean` | true if item prefetch is enabled, false otherwise
|
**See also:**
- [setItemPrefetchEnabled(boolean)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setItemPrefetchEnabled(boolean))
### isLayoutHierarchical
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean isLayoutHierarchical (RecyclerView.Recycler recycler,
RecyclerView.State state)
```
Returns whether layout is hierarchical or not to be used for accessibility.
Default implementation returns false.
| Parameters ||
|------------|----------------------------------------------------------------------------------------------------------------|
| `recycler` | `RecyclerView.Recycler`: The Recycler that can be used to convert view positions into adapter positions
|
| `state` | `RecyclerView.State`: The current state of RecyclerView
|
| Returns ||
|-----------|----------------------------------------|
| `boolean` | True if layout is hierarchical.
|
### isMeasurementCacheEnabled
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean isMeasurementCacheEnabled ()
```
In addition to the View Framework's measurement cache, RecyclerView uses its own additional measurement cache for its children to avoid re-measuring them when not necessary. It is on by default but it can be turned off via[setMeasurementCacheEnabled(boolean)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setMeasurementCacheEnabled(boolean)).
| Returns ||
|-----------|---------------------------------------------------------------|
| `boolean` | True if measurement cache is enabled, false otherwise.
|
**See also:**
- [setMeasurementCacheEnabled(boolean)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setMeasurementCacheEnabled(boolean))
### isSmoothScrolling
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean isSmoothScrolling ()
```
| Returns ||
|-----------|----------------------------------------------------------------------------|
| `boolean` | true if RecyclerView is currently in the state of smooth scrolling.
|
### isViewPartiallyVisible
added in[version 25.4.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean isViewPartiallyVisible (View child,
boolean completelyVisible,
boolean acceptEndPointInclusion)
```
Returns whether the given child view is partially or fully visible within the padded bounded area of RecyclerView, depending on the input parameters. A view is partially visible if it has non-zero overlap with RV's padded bounded area. If acceptEndPointInclusion flag is set to true, it's also considered partially visible if it's located outside RV's bounds and it's hitting either RV's start or end bounds.
| Parameters ||
|---------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `child` | `View`: The child view to be examined.
|
| `completelyVisible` | `boolean`: If true, the method returns true if and only if the child is completely visible. If false, the method returns true if and only if the child is only partially visible (that is it will return false if the child is either completely visible or out of RV's bounds).
|
| `acceptEndPointInclusion` | `boolean`: If the view's endpoint intersection with RV's start of end bounds is enough to consider it partially visible, false otherwise.
|
| Returns ||
|-----------|--------------------------------------------------------------------------------|
| `boolean` | True if the given child is partially or fully visible, false otherwise.
|
### layoutDecorated
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void layoutDecorated (View child,
int left,
int top,
int right,
int bottom)
```
Lay out the given child view within the RecyclerView using coordinates that include any current[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration).
LayoutManagers should prefer working in sizes and coordinates that include item decoration insets whenever possible. This allows the LayoutManager to effectively ignore decoration insets within measurement and layout code. See the following methods:
- [layoutDecoratedWithMargins(View, int, int, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#layoutDecoratedWithMargins(android.view.View, int, int, int, int))
- [getDecoratedBoundsWithMargins(View, Rect)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedBoundsWithMargins(android.view.View, android.graphics.Rect))
- [measureChild(View, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#measureChild(android.view.View, int, int))
- [measureChildWithMargins(View, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#measureChildWithMargins(android.view.View, int, int))
- [getDecoratedLeft(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedLeft(android.view.View))
- [getDecoratedTop(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedTop(android.view.View))
- [getDecoratedRight(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedRight(android.view.View))
- [getDecoratedBottom(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedBottom(android.view.View))
- [getDecoratedMeasuredWidth(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedMeasuredWidth(android.view.View))
- [getDecoratedMeasuredHeight(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedMeasuredHeight(android.view.View))
| Parameters ||
|----------|-----------------------------------------------------------------|
| `child` | `View`: Child to lay out
|
| `left` | `int`: Left edge, with item decoration insets included
|
| `top` | `int`: Top edge, with item decoration insets included
|
| `right` | `int`: Right edge, with item decoration insets included
|
| `bottom` | `int`: Bottom edge, with item decoration insets included
|
**See also:**
- [layout(int, int, int, int)](https://developer.android.com/https://developer.android.com/reference/android/view/View#layout(int, int, int, int))
- [layoutDecoratedWithMargins(View, int, int, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#layoutDecoratedWithMargins(android.view.View, int, int, int, int))
### layoutDecoratedWithMargins
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void layoutDecoratedWithMargins (View child,
int left,
int top,
int right,
int bottom)
```
Lay out the given child view within the RecyclerView using coordinates that include any current[ItemDecorations](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration)and margins.
LayoutManagers should prefer working in sizes and coordinates that include item decoration insets whenever possible. This allows the LayoutManager to effectively ignore decoration insets within measurement and layout code. See the following methods:
- [layoutDecorated(View, int, int, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#layoutDecorated(android.view.View, int, int, int, int))
- [measureChild(View, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#measureChild(android.view.View, int, int))
- [measureChildWithMargins(View, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#measureChildWithMargins(android.view.View, int, int))
- [getDecoratedLeft(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedLeft(android.view.View))
- [getDecoratedTop(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedTop(android.view.View))
- [getDecoratedRight(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedRight(android.view.View))
- [getDecoratedBottom(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedBottom(android.view.View))
- [getDecoratedMeasuredWidth(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedMeasuredWidth(android.view.View))
- [getDecoratedMeasuredHeight(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getDecoratedMeasuredHeight(android.view.View))
| Parameters ||
|----------|-----------------------------------------------------------------------------------|
| `child` | `View`: Child to lay out
|
| `left` | `int`: Left edge, with item decoration insets and left margin included
|
| `top` | `int`: Top edge, with item decoration insets and top margin included
|
| `right` | `int`: Right edge, with item decoration insets and right margin included
|
| `bottom` | `int`: Bottom edge, with item decoration insets and bottom margin included
|
**See also:**
- [layout(int, int, int, int)](https://developer.android.com/https://developer.android.com/reference/android/view/View#layout(int, int, int, int))
- [layoutDecorated(View, int, int, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#layoutDecorated(android.view.View, int, int, int, int))
### measureChild
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void measureChild (View child,
int widthUsed,
int heightUsed)
```
Measure a child view using standard measurement policy, taking the padding of the parent RecyclerView and any added item decorations into account.
If the RecyclerView can be scrolled in either dimension the caller may pass 0 as the widthUsed or heightUsed parameters as they will be irrelevant.
| Parameters ||
|--------------|-------------------------------------------------------------------------------|
| `child` | `View`: Child view to measure
|
| `widthUsed` | `int`: Width in pixels currently consumed by other views, if relevant
|
| `heightUsed` | `int`: Height in pixels currently consumed by other views, if relevant
|
### measureChildWithMargins
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void measureChildWithMargins (View child,
int widthUsed,
int heightUsed)
```
Measure a child view using standard measurement policy, taking the padding of the parent RecyclerView, any added item decorations and the child margins into account.
If the RecyclerView can be scrolled in either dimension the caller may pass 0 as the widthUsed or heightUsed parameters as they will be irrelevant.
| Parameters ||
|--------------|-------------------------------------------------------------------------------|
| `child` | `View`: Child view to measure
|
| `widthUsed` | `int`: Width in pixels currently consumed by other views, if relevant
|
| `heightUsed` | `int`: Height in pixels currently consumed by other views, if relevant
|
### moveView
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void moveView (int fromIndex,
int toIndex)
```
Moves a View from one position to another.
| Parameters ||
|-------------|----------------------------------------|
| `fromIndex` | `int`: The View's initial index
|
| `toIndex` | `int`: The View's target index
|
### offsetChildrenHorizontal
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void offsetChildrenHorizontal (int dx)
```
Offset all child views attached to the parent RecyclerView by dx pixels along the horizontal axis.
| Parameters ||
|------|-----------------------------------|
| `dx` | `int`: Pixels to offset by
|
### offsetChildrenVertical
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void offsetChildrenVertical (int dy)
```
Offset all child views attached to the parent RecyclerView by dy pixels along the vertical axis.
| Parameters ||
|------|-----------------------------------|
| `dy` | `int`: Pixels to offset by
|
### onAdapterChanged
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onAdapterChanged (Adapter oldAdapter,
Adapter newAdapter)
```
Called if the RecyclerView this LayoutManager is bound to has a different adapter set via[setAdapter(Adapter)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#setAdapter(android.support.v7.widget.RecyclerView.Adapter))or[swapAdapter(Adapter, boolean)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#swapAdapter(android.support.v7.widget.RecyclerView.Adapter, boolean)). The LayoutManager may use this opportunity to clear caches and configure state such that it can relayout appropriately with the new data and potentially new view types.
The default implementation removes all currently attached views.
| Parameters ||
|--------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `oldAdapter` | `Adapter`: The previous adapter instance. Will be null if there was previously no adapter.
|
| `newAdapter` | `Adapter`: The new adapter instance. Might be null if[setAdapter(RecyclerView.Adapter)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#setAdapter(android.support.v7.widget.RecyclerView.Adapter))is called with`null`.
|
### onAddFocusables
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean onAddFocusables (RecyclerView recyclerView,
ArrayList views,
int direction,
int focusableMode)
```
Called to populate focusable views within the RecyclerView.
The LayoutManager implementation should return`true`if the default behavior of[addFocusables(java.util.ArrayList, int)](https://developer.android.com/reference/android/view/View.html#addFocusables(java.util.ArrayList, int))should be suppressed.
The default implementation returns`false`to trigger RecyclerView to fall back to the default ViewGroup behavior.
| Parameters ||
|-----------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `recyclerView` | `RecyclerView`: The RecyclerView hosting this LayoutManager
|
| `views` | `ArrayList`: List of output views. This method should add valid focusable views to this list.
|
| `direction` | `int`: One of[FOCUS_UP](https://developer.android.com/reference/android/view/View.html#FOCUS_UP),[FOCUS_DOWN](https://developer.android.com/reference/android/view/View.html#FOCUS_DOWN),[FOCUS_LEFT](https://developer.android.com/reference/android/view/View.html#FOCUS_LEFT),[FOCUS_RIGHT](https://developer.android.com/reference/android/view/View.html#FOCUS_RIGHT),[FOCUS_BACKWARD](https://developer.android.com/reference/android/view/View.html#FOCUS_BACKWARD),[FOCUS_FORWARD](https://developer.android.com/reference/android/view/View.html#FOCUS_FORWARD)
|
| `focusableMode` | `int`: The type of focusables to be added.
|
| Returns ||
|-----------|----------------------------------------------------------------------------------------------------------|
| `boolean` | true to suppress the default behavior, false to add default focusables after this method returns.
|
**See also:**
- [FOCUSABLES_ALL](https://developer.android.com/https://developer.android.com/reference/android/view/View#FOCUSABLES_ALL)
- [FOCUSABLES_TOUCH_MODE](https://developer.android.com/https://developer.android.com/reference/android/view/View#FOCUSABLES_TOUCH_MODE)
### onAttachedToWindow
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onAttachedToWindow (RecyclerView view)
```
Called when this LayoutManager is both attached to a RecyclerView and that RecyclerView is attached to a window.
If the RecyclerView is re-attached with the same LayoutManager and Adapter, it may not call[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))if nothing has changed and a layout was not requested on the RecyclerView while it was detached.
Subclass implementations should always call through to the superclass implementation.
| Parameters ||
|--------|------------------------------------------------------------------------|
| `view` | `RecyclerView`: The RecyclerView this LayoutManager is bound to
|
**See also:**
- [onDetachedFromWindow(RecyclerView, Recycler)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onDetachedFromWindow(android.support.v7.widget.RecyclerView, android.support.v7.widget.RecyclerView.Recycler))
### onDetachedFromWindow
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onDetachedFromWindow (RecyclerView view,
RecyclerView.Recycler recycler)
```
Called when this LayoutManager is detached from its parent RecyclerView or when its parent RecyclerView is detached from its window.
LayoutManager should clear all of its View references as another LayoutManager might be assigned to the RecyclerView.
If the RecyclerView is re-attached with the same LayoutManager and Adapter, it may not call[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))if nothing has changed and a layout was not requested on the RecyclerView while it was detached.
If your LayoutManager has View references that it cleans in on-detach, it should also call[requestLayout()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#requestLayout())to ensure that it is re-laid out when RecyclerView is re-attached.
Subclass implementations should always call through to the superclass implementation.
| Parameters ||
|------------|----------------------------------------------------------------------------------------------------------------------------|
| `view` | `RecyclerView`: The RecyclerView this LayoutManager is bound to
|
| `recycler` | `RecyclerView.Recycler`: The recycler to use if you prefer to recycle your children instead of keeping them around.
|
**See also:**
- [onAttachedToWindow(RecyclerView)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onAttachedToWindow(android.support.v7.widget.RecyclerView))
### onDetachedFromWindow
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onDetachedFromWindow (RecyclerView view)
```
**This method was deprecated in API level 22.1.0.**
override[onDetachedFromWindow(RecyclerView, Recycler)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onDetachedFromWindow(android.support.v7.widget.RecyclerView, android.support.v7.widget.RecyclerView.Recycler))
| Parameters ||
|--------|-----------------------|
| `view` | `RecyclerView`
|
### onFocusSearchFailed
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
View onFocusSearchFailed (View focused,
int direction,
RecyclerView.Recycler recycler,
RecyclerView.State state)
```
Called when searching for a focusable view in the given direction has failed for the current content of the RecyclerView.
This is the LayoutManager's opportunity to populate views in the given direction to fulfill the request if it can. The LayoutManager should attach and return the view to be focused, if a focusable view in the given direction is found. Otherwise, if all the existing (or the newly populated views) are unfocusable, it returns the next unfocusable view to become visible on the screen. This unfocusable view is typically the first view that's either partially or fully out of RV's padded bounded area in the given direction. The default implementation returns null.
| Parameters ||
|-------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `focused` | `View`: The currently focused view
|
| `direction` | `int`: One of[FOCUS_UP](https://developer.android.com/reference/android/view/View.html#FOCUS_UP),[FOCUS_DOWN](https://developer.android.com/reference/android/view/View.html#FOCUS_DOWN),[FOCUS_LEFT](https://developer.android.com/reference/android/view/View.html#FOCUS_LEFT),[FOCUS_RIGHT](https://developer.android.com/reference/android/view/View.html#FOCUS_RIGHT),[FOCUS_BACKWARD](https://developer.android.com/reference/android/view/View.html#FOCUS_BACKWARD),[FOCUS_FORWARD](https://developer.android.com/reference/android/view/View.html#FOCUS_FORWARD)or 0 for not applicable
|
| `recycler` | `RecyclerView.Recycler`: The recycler to use for obtaining views for currently offscreen items
|
| `state` | `RecyclerView.State`: Transient state of RecyclerView
|
| Returns ||
|------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------|
| [View](https://developer.android.com/reference/android/view/View.html) | The chosen view to be focused if a focusable view is found, otherwise an unfocusable view to become visible onto the screen, else null.
|
### onInitializeAccessibilityEvent
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onInitializeAccessibilityEvent (AccessibilityEvent event)
```
| Parameters ||
|---------|-----------------------------|
| `event` | `AccessibilityEvent`
|
### onInitializeAccessibilityEvent
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onInitializeAccessibilityEvent (RecyclerView.Recycler recycler,
RecyclerView.State state,
AccessibilityEvent event)
```
Called by the accessibility delegate to initialize an accessibility event.
Default implementation adds item count and scroll information to the event.
| Parameters ||
|------------|----------------------------------------------------------------------------------------------------------------|
| `recycler` | `RecyclerView.Recycler`: The Recycler that can be used to convert view positions into adapter positions
|
| `state` | `RecyclerView.State`: The current state of RecyclerView
|
| `event` | `AccessibilityEvent`: The event instance to initialize
|
**See also:**
- [onInitializeAccessibilityEvent(android.view.accessibility.AccessibilityEvent)](https://developer.android.com/https://developer.android.com/reference/android/view/View#onInitializeAccessibilityEvent(android.view.accessibility.AccessibilityEvent))
### onInitializeAccessibilityNodeInfo
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onInitializeAccessibilityNodeInfo (RecyclerView.Recycler recycler,
RecyclerView.State state,
AccessibilityNodeInfoCompat info)
```
Called by the AccessibilityDelegate when the information about the current layout should be populated.
Default implementation adds a[AccessibilityNodeInfoCompat.CollectionInfoCompat](https://developer.android.com/reference/android/support/v4/view/accessibility/AccessibilityNodeInfoCompat.CollectionInfoCompat).
You should override[getRowCountForAccessibility(RecyclerView.Recycler, RecyclerView.State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getRowCountForAccessibility(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State)),[getColumnCountForAccessibility(RecyclerView.Recycler, RecyclerView.State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getColumnCountForAccessibility(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State)),[isLayoutHierarchical(RecyclerView.Recycler, RecyclerView.State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isLayoutHierarchical(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))and[getSelectionModeForAccessibility(RecyclerView.Recycler, RecyclerView.State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getSelectionModeForAccessibility(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))for more accurate accessibility information.
| Parameters ||
|------------|----------------------------------------------------------------------------------------------------------------|
| `recycler` | `RecyclerView.Recycler`: The Recycler that can be used to convert view positions into adapter positions
|
| `state` | `RecyclerView.State`: The current state of RecyclerView
|
| `info` | `AccessibilityNodeInfoCompat`: The info that should be filled by the LayoutManager
|
**See also:**
- [onInitializeAccessibilityNodeInfo(android.view.accessibility.AccessibilityNodeInfo)](https://developer.android.com/https://developer.android.com/reference/android/view/View#onInitializeAccessibilityNodeInfo(android.view.accessibility.AccessibilityNodeInfo))
- [getRowCountForAccessibility(RecyclerView.Recycler, RecyclerView.State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getRowCountForAccessibility(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))
- [getColumnCountForAccessibility(RecyclerView.Recycler, RecyclerView.State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getColumnCountForAccessibility(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))
- [isLayoutHierarchical(RecyclerView.Recycler, RecyclerView.State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isLayoutHierarchical(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))
- [getSelectionModeForAccessibility(RecyclerView.Recycler, RecyclerView.State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#getSelectionModeForAccessibility(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))
### onInitializeAccessibilityNodeInfoForItem
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onInitializeAccessibilityNodeInfoForItem (RecyclerView.Recycler recycler,
RecyclerView.State state,
View host,
AccessibilityNodeInfoCompat info)
```
Called by the AccessibilityDelegate when the accessibility information for a specific item should be populated.
Default implementation adds basic positioning information about the item.
| Parameters ||
|------------|----------------------------------------------------------------------------------------------------------------|
| `recycler` | `RecyclerView.Recycler`: The Recycler that can be used to convert view positions into adapter positions
|
| `state` | `RecyclerView.State`: The current state of RecyclerView
|
| `host` | `View`: The child for which accessibility node info should be populated
|
| `info` | `AccessibilityNodeInfoCompat`: The info to fill out about the item
|
**See also:**
- [onInitializeAccessibilityNodeInfoForItem(View, int, android.view.accessibility.AccessibilityNodeInfo)](https://developer.android.com/https://developer.android.com/reference/android/widget/AbsListView#onInitializeAccessibilityNodeInfoForItem(android.view.View, int, android.view.accessibility.AccessibilityNodeInfo))
### onInterceptFocusSearch
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
View onInterceptFocusSearch (View focused,
int direction)
```
This method gives a LayoutManager an opportunity to intercept the initial focus search before the default behavior of[FocusFinder](https://developer.android.com/reference/android/view/FocusFinder.html)is used. If this method returns null FocusFinder will attempt to find a focusable child view. If it fails then[onFocusSearchFailed(View, int, RecyclerView.Recycler, RecyclerView.State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onFocusSearchFailed(android.view.View, int, android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))will be called to give the LayoutManager an opportunity to add new views for items that did not have attached views representing them. The LayoutManager should not add or remove views from this method.
| Parameters ||
|-------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `focused` | `View`: The currently focused view
|
| `direction` | `int`: One of[FOCUS_UP](https://developer.android.com/reference/android/view/View.html#FOCUS_UP),[FOCUS_DOWN](https://developer.android.com/reference/android/view/View.html#FOCUS_DOWN),[FOCUS_LEFT](https://developer.android.com/reference/android/view/View.html#FOCUS_LEFT),[FOCUS_RIGHT](https://developer.android.com/reference/android/view/View.html#FOCUS_RIGHT),[FOCUS_BACKWARD](https://developer.android.com/reference/android/view/View.html#FOCUS_BACKWARD),[FOCUS_FORWARD](https://developer.android.com/reference/android/view/View.html#FOCUS_FORWARD)
|
| Returns ||
|------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------|
| [View](https://developer.android.com/reference/android/view/View.html) | A descendant view to focus or null to fall back to default behavior. The default implementation returns null.
|
### onItemsAdded
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onItemsAdded (RecyclerView recyclerView,
int positionStart,
int itemCount)
```
Called when items have been added to the adapter. The LayoutManager may choose to requestLayout if the inserted items would require refreshing the currently visible set of child views. (e.g. currently empty space would be filled by appended items, etc.)
### onItemsChanged
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onItemsChanged (RecyclerView recyclerView)
```
Called in response to a call to[notifyDataSetChanged()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Adapter#notifyDataSetChanged())or[swapAdapter(Adapter, boolean)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#swapAdapter(android.support.v7.widget.RecyclerView.Adapter, boolean))()} and signals that the the entire data set has changed.
### onItemsMoved
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onItemsMoved (RecyclerView recyclerView,
int from,
int to,
int itemCount)
```
Called when an item is moved withing the adapter.
Note that, an item may also change position in response to another ADD/REMOVE/MOVE operation. This callback is only called if and only if[notifyItemMoved(int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Adapter#notifyItemMoved(int, int))is called.
### onItemsRemoved
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onItemsRemoved (RecyclerView recyclerView,
int positionStart,
int itemCount)
```
Called when items have been removed from the adapter.
### onItemsUpdated
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onItemsUpdated (RecyclerView recyclerView,
int positionStart,
int itemCount)
```
Called when items have been changed in the adapter. To receive payload, override[onItemsUpdated(RecyclerView, int, int, Object)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onItemsUpdated(android.support.v7.widget.RecyclerView, int, int, java.lang.Object))instead, then this callback will not be invoked.
### onItemsUpdated
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onItemsUpdated (RecyclerView recyclerView,
int positionStart,
int itemCount,
Object payload)
```
Called when items have been changed in the adapter and with optional payload. Default implementation calls[onItemsUpdated(RecyclerView, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onItemsUpdated(android.support.v7.widget.RecyclerView, int, int)).
### onLayoutChildren
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onLayoutChildren (RecyclerView.Recycler recycler,
RecyclerView.State state)
```
Lay out all relevant child views from the given adapter. The LayoutManager is in charge of the behavior of item animations. By default, RecyclerView has a non-null[ItemAnimator](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#getItemAnimator()), and simple item animations are enabled. This means that add/remove operations on the adapter will result in animations to add new or appearing items, removed or disappearing items, and moved items. If a LayoutManager returns false from[supportsPredictiveItemAnimations()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#supportsPredictiveItemAnimations()), which is the default, and runs a normal layout operation during[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State)), the RecyclerView will have enough information to run those animations in a simple way. For example, the default ItemAnimator,[DefaultItemAnimator](https://developer.android.com/reference/android/support/v7/widget/DefaultItemAnimator), will simply fade views in and out, whether they are actually added/removed or whether they are moved on or off the screen due to other add/remove operations.
A LayoutManager wanting a better item animation experience, where items can be animated onto and off of the screen according to where the items exist when they are not on screen, then the LayoutManager should return true from[supportsPredictiveItemAnimations()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#supportsPredictiveItemAnimations())and add additional logic to[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State)). Supporting predictive animations means that[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))will be called twice; once as a "pre" layout step to determine where items would have been prior to a real layout, and again to do the "real" layout. In the pre-layout phase, items will remember their pre-layout positions to allow them to be laid out appropriately. Also,[removed](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutParams#isItemRemoved())items will be returned from the scrap to help determine correct placement of other items. These removed items should not be added to the child list, but should be used to help calculate correct positioning of other views, including views that were not previously onscreen (referred to as APPEARING views), but whose pre-layout offscreen position can be determined given the extra information about the pre-layout removed views.
The second layout pass is the real layout in which only non-removed views will be used. The only additional requirement during this pass is, if[supportsPredictiveItemAnimations()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#supportsPredictiveItemAnimations())returns true, to note which views exist in the child list prior to layout and which are not there after layout (referred to as DISAPPEARING views), and to position/layout those views appropriately, without regard to the actual bounds of the RecyclerView. This allows the animation system to know the location to which to animate these disappearing views.
The default LayoutManager implementations for RecyclerView handle all of these requirements for animations already. Clients of RecyclerView can either use one of these layout managers directly or look at their implementations of onLayoutChildren() to see how they account for the APPEARING and DISAPPEARING views.
| Parameters ||
|------------|------------------------------------------------------------------------------------------------------|
| `recycler` | `RecyclerView.Recycler`: Recycler to use for fetching potentially cached views for a position
|
| `state` | `RecyclerView.State`: Transient state of RecyclerView
|
### onLayoutCompleted
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onLayoutCompleted (RecyclerView.State state)
```
Called after a full layout calculation is finished. The layout calculation may include multiple[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))calls due to animations or layout measurement but it will include only one[onLayoutCompleted(State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutCompleted(android.support.v7.widget.RecyclerView.State))call. This method will be called at the end of[layout(int, int, int, int)](https://developer.android.com/reference/android/view/View.html#layout(int, int, int, int))call.
This is a good place for the LayoutManager to do some cleanup like pending scroll position, saved state etc.
| Parameters ||
|---------|--------------------------------------------------------------|
| `state` | `RecyclerView.State`: Transient state of RecyclerView
|
### onMeasure
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onMeasure (RecyclerView.Recycler recycler,
RecyclerView.State state,
int widthSpec,
int heightSpec)
```
Measure the attached RecyclerView. Implementations must call[setMeasuredDimension(int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setMeasuredDimension(int, int))before returning.
It is strongly advised to use the AutoMeasure mechanism by overriding[isAutoMeasureEnabled()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isAutoMeasureEnabled())to return true as AutoMeasure handles all the standard measure cases including when the RecyclerView's layout_width or layout_height have been set to wrap_content. If[isAutoMeasureEnabled()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isAutoMeasureEnabled())is overridden to return true, this method should not be overridden.
The default implementation will handle EXACTLY measurements and respect the minimum width and height properties of the host RecyclerView if measured as UNSPECIFIED. AT_MOST measurements will be treated as EXACTLY and the RecyclerView will consume all available space.
| Parameters ||
|--------------|--------------------------------------------------------------------------------------------------------------------|
| `recycler` | `RecyclerView.Recycler`: Recycler
|
| `state` | `RecyclerView.State`: Transient state of RecyclerView
|
| `widthSpec` | `int`: Width[View.MeasureSpec](https://developer.android.com/reference/android/view/View.MeasureSpec.html)
|
| `heightSpec` | `int`: Height[View.MeasureSpec](https://developer.android.com/reference/android/view/View.MeasureSpec.html)
|
**See also:**
- [isAutoMeasureEnabled()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isAutoMeasureEnabled())
- [setMeasuredDimension(int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setMeasuredDimension(int, int))
### onRequestChildFocus
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean onRequestChildFocus (RecyclerView parent,
View child,
View focused)
```
**This method was deprecated in API level 22.1.0.**
Use[onRequestChildFocus(RecyclerView, State, View, View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onRequestChildFocus(android.support.v7.widget.RecyclerView, android.support.v7.widget.RecyclerView.State, android.view.View, android.view.View))
| Parameters ||
|-----------|-----------------------|
| `parent` | `RecyclerView`
|
| `child` | `View`
|
| `focused` | `View`
|
| Returns ||
|-----------|--------|
| `boolean` |
|
### onRequestChildFocus
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean onRequestChildFocus (RecyclerView parent,
RecyclerView.State state,
View child,
View focused)
```
Called when a descendant view of the RecyclerView requests focus.
A LayoutManager wishing to keep focused views aligned in a specific portion of the view may implement that behavior in an override of this method.
If the LayoutManager executes different behavior that should override the default behavior of scrolling the focused child on screen instead of running alongside it, this method should return true.
| Parameters ||
|-----------|---------------------------------------------------------------------------------------------|
| `parent` | `RecyclerView`: The RecyclerView hosting this LayoutManager
|
| `state` | `RecyclerView.State`: Current state of RecyclerView
|
| `child` | `View`: Direct child of the RecyclerView containing the newly focused view
|
| `focused` | `View`: The newly focused view. This may be the same view as child or it may be null
|
| Returns ||
|-----------|-----------------------------------------------------------------|
| `boolean` | true if the default scroll behavior should be suppressed
|
### onRestoreInstanceState
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onRestoreInstanceState (Parcelable state)
```
| Parameters ||
|---------|---------------------|
| `state` | `Parcelable`
|
### onSaveInstanceState
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
Parcelable onSaveInstanceState ()
```
Called when the LayoutManager should save its state. This is a good time to save your scroll position, configuration and anything else that may be required to restore the same layout state if the LayoutManager is recreated.
RecyclerView does NOT verify if the LayoutManager has changed between state save and restore. This will let you share information between your LayoutManagers but it is also your responsibility to make sure they use the same parcelable class.
| Returns ||
|----------------------------------------------------------------------------------|--------------------------------------------------------------------------------|
| [Parcelable](https://developer.android.com/reference/android/os/Parcelable.html) | Necessary information for LayoutManager to be able to restore its state
|
### onScrollStateChanged
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void onScrollStateChanged (int state)
```
RecyclerView calls this method to notify LayoutManager that scroll state has changed.
| Parameters ||
|---------|-----------------------------------------------------|
| `state` | `int`: The new scroll state for RecyclerView
|
### performAccessibilityAction
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean performAccessibilityAction (RecyclerView.Recycler recycler,
RecyclerView.State state,
int action,
Bundle args)
```
Called by AccessibilityDelegate when an action is requested from the RecyclerView.
| Parameters ||
|------------|----------------------------------------------------------------------------------------------------------------|
| `recycler` | `RecyclerView.Recycler`: The Recycler that can be used to convert view positions into adapter positions
|
| `state` | `RecyclerView.State`: The current state of RecyclerView
|
| `action` | `int`: The action to perform
|
| `args` | `Bundle`: Optional action arguments
|
| Returns ||
|-----------|--------|
| `boolean` |
|
**See also:**
- [performAccessibilityAction(int, android.os.Bundle)](https://developer.android.com/https://developer.android.com/reference/android/view/View#performAccessibilityAction(int, android.os.Bundle))
### performAccessibilityActionForItem
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean performAccessibilityActionForItem (RecyclerView.Recycler recycler,
RecyclerView.State state,
View view,
int action,
Bundle args)
```
Called by AccessibilityDelegate when an accessibility action is requested on one of the children of LayoutManager.
Default implementation does not do anything.
| Parameters ||
|------------|----------------------------------------------------------------------------------------------------------------|
| `recycler` | `RecyclerView.Recycler`: The Recycler that can be used to convert view positions into adapter positions
|
| `state` | `RecyclerView.State`: The current state of RecyclerView
|
| `view` | `View`: The child view on which the action is performed
|
| `action` | `int`: The action to perform
|
| `args` | `Bundle`: Optional action arguments
|
| Returns ||
|-----------|----------------------------------|
| `boolean` | true if action is handled
|
**See also:**
- [performAccessibilityAction(int, android.os.Bundle)](https://developer.android.com/https://developer.android.com/reference/android/view/View#performAccessibilityAction(int, android.os.Bundle))
### postOnAnimation
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void postOnAnimation (Runnable action)
```
Causes the Runnable to execute on the next animation time step. The runnable will be run on the user interface thread.
Calling this method when LayoutManager is not attached to a RecyclerView has no effect.
| Parameters ||
|----------|--------------------------------------------------------|
| `action` | `Runnable`: The Runnable that will be executed.
|
**See also:**
- [removeCallbacks(Runnable)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#removeCallbacks(java.lang.Runnable))
### removeAllViews
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void removeAllViews ()
```
Remove all views from the currently attached RecyclerView. This will not recycle any of the affected views; the LayoutManager is responsible for doing so if desired.
### removeAndRecycleAllViews
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void removeAndRecycleAllViews (RecyclerView.Recycler recycler)
```
Removes all views and recycles them using the given recycler.
If you want to clean cached views as well, you should call[clear()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler#clear())too.
If a View is marked as "ignored", it is not removed nor recycled.
| Parameters ||
|------------|---------------------------------------------------------------------|
| `recycler` | `RecyclerView.Recycler`: Recycler to use to recycle children
|
**See also:**
- [removeAndRecycleView(View, Recycler)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#removeAndRecycleView(android.view.View, android.support.v7.widget.RecyclerView.Recycler))
- [removeAndRecycleViewAt(int, Recycler)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#removeAndRecycleViewAt(int, android.support.v7.widget.RecyclerView.Recycler))
- [ignoreView(View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#ignoreView(android.view.View))
### removeAndRecycleView
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void removeAndRecycleView (View child,
RecyclerView.Recycler recycler)
```
Remove a child view and recycle it using the given Recycler.
| Parameters ||
|------------|------------------------------------------------------------------|
| `child` | `View`: Child to remove and recycle
|
| `recycler` | `RecyclerView.Recycler`: Recycler to use to recycle child
|
### removeAndRecycleViewAt
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void removeAndRecycleViewAt (int index,
RecyclerView.Recycler recycler)
```
Remove a child view and recycle it using the given Recycler.
| Parameters ||
|------------|------------------------------------------------------------------|
| `index` | `int`: Index of child to remove and recycle
|
| `recycler` | `RecyclerView.Recycler`: Recycler to use to recycle child
|
### removeCallbacks
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean removeCallbacks (Runnable action)
```
Removes the specified Runnable from the message queue.
Calling this method when LayoutManager is not attached to a RecyclerView has no effect.
| Parameters ||
|----------|---------------------------------------------------------------------------|
| `action` | `Runnable`: The Runnable to remove from the message handling queue
|
| Returns ||
|-----------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `boolean` | true if RecyclerView could ask the Handler to remove the Runnable, false otherwise. When the returned value is true, the Runnable may or may not have been actually removed from the message queue (for instance, if the Runnable was not in the queue already.)
|
**See also:**
- [postOnAnimation(Runnable)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#postOnAnimation(java.lang.Runnable))
### removeDetachedView
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void removeDetachedView (View child)
```
Finish removing a view that was previously temporarily[detached](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#detachView(android.view.View)).
| Parameters ||
|---------|-----------------------------------------|
| `child` | `View`: Detached child to remove
|
### removeView
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void removeView (View child)
```
Remove a view from the currently attached RecyclerView if needed. LayoutManagers should use this method to completely remove a child view that is no longer needed. LayoutManagers should strongly consider recycling removed views using[recycleView(android.view.View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler#recycleView(android.view.View)).
| Parameters ||
|---------|-------------------------------|
| `child` | `View`: View to remove
|
### removeViewAt
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void removeViewAt (int index)
```
Remove a view from the currently attached RecyclerView if needed. LayoutManagers should use this method to completely remove a child view that is no longer needed. LayoutManagers should strongly consider recycling removed views using[recycleView(android.view.View)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler#recycleView(android.view.View)).
| Parameters ||
|---------|-------------------------------------------------|
| `index` | `int`: Index of the child view to remove
|
### requestChildRectangleOnScreen
added in[version 25.4.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean requestChildRectangleOnScreen (RecyclerView parent,
View child,
Rect rect,
boolean immediate,
boolean focusedChildVisible)
```
Requests that the given child of the RecyclerView be positioned onto the screen. This method can be called for both unfocusable and focusable child views. For unfocusable child views, focusedChildVisible is typically true in which case, layout manager makes the child view visible only if the currently focused child stays in-bounds of RV.
| Parameters ||
|-----------------------|-----------------------------------------------------------------------------------------------|
| `parent` | `RecyclerView`: The parent RecyclerView.
|
| `child` | `View`: The direct child making the request.
|
| `rect` | `Rect`: The rectangle in the child's coordinates the child wishes to be on the screen.
|
| `immediate` | `boolean`: True to forbid animated or delayed scrolling, false otherwise
|
| `focusedChildVisible` | `boolean`: Whether the currently focused view must stay visible.
|
| Returns ||
|-----------|-----------------------------------------------------------|
| `boolean` | Whether the group scrolled to handle the operation
|
### requestChildRectangleOnScreen
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean requestChildRectangleOnScreen (RecyclerView parent,
View child,
Rect rect,
boolean immediate)
```
Called when a child of the RecyclerView wants a particular rectangle to be positioned onto the screen. See[requestChildRectangleOnScreen(android.view.View, android.graphics.Rect, boolean)](https://developer.android.com/reference/android/view/ViewParent.html#requestChildRectangleOnScreen(android.view.View, android.graphics.Rect, boolean))for more details.
The base implementation will attempt to perform a standard programmatic scroll to bring the given rect into view, within the padded area of the RecyclerView.
| Parameters ||
|-------------|-----------------------------------------------------------------------------------------------|
| `parent` | `RecyclerView`
|
| `child` | `View`: The direct child making the request.
|
| `rect` | `Rect`: The rectangle in the child's coordinates the child wishes to be on the screen.
|
| `immediate` | `boolean`: True to forbid animated or delayed scrolling, false otherwise
|
| Returns ||
|-----------|-----------------------------------------------------------|
| `boolean` | Whether the group scrolled to handle the operation
|
### requestLayout
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void requestLayout ()
```
Calls`RecyclerView#requestLayout`on the underlying RecyclerView
### requestSimpleAnimationsInNextLayout
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void requestSimpleAnimationsInNextLayout ()
```
A LayoutManager can call this method to force RecyclerView to run simple animations in the next layout pass, even if there is not any trigger to do so. (e.g. adapter data change).
Note that, calling this method will not guarantee that RecyclerView will run animations at all. For example, if there is not any[RecyclerView.ItemAnimator](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemAnimator)set, RecyclerView will not run any animations but will still clear this flag after the layout is complete.
### scrollHorizontallyBy
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int scrollHorizontallyBy (int dx,
RecyclerView.Recycler recycler,
RecyclerView.State state)
```
Scroll horizontally by dx pixels in screen coordinates and return the distance traveled. The default implementation does nothing and returns 0.
| Parameters ||
|------------|------------------------------------------------------------------------------------------------------|
| `dx` | `int`: distance to scroll by in pixels. X increases as scroll position approaches the right.
|
| `recycler` | `RecyclerView.Recycler`: Recycler to use for fetching potentially cached views for a position
|
| `state` | `RecyclerView.State`: Transient state of RecyclerView
|
| Returns ||
|-------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `int` | The actual distance scrolled. The return value will be negative if dx was negative and scrolling proceeeded in that direction.`Math.abs(result)`may be less than dx if a boundary was reached.
|
### scrollToPosition
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void scrollToPosition (int position)
```
Scroll to the specified adapter position. Actual position of the item on the screen depends on the LayoutManager implementation.
| Parameters ||
|------------|------------------------------------------------|
| `position` | `int`: Scroll to this adapter position.
|
### scrollVerticallyBy
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
int scrollVerticallyBy (int dy,
RecyclerView.Recycler recycler,
RecyclerView.State state)
```
Scroll vertically by dy pixels in screen coordinates and return the distance traveled. The default implementation does nothing and returns 0.
| Parameters ||
|------------|------------------------------------------------------------------------------------------------------|
| `dy` | `int`: distance to scroll in pixels. Y increases as scroll position approaches the bottom.
|
| `recycler` | `RecyclerView.Recycler`: Recycler to use for fetching potentially cached views for a position
|
| `state` | `RecyclerView.State`: Transient state of RecyclerView
|
| Returns ||
|-------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `int` | The actual distance scrolled. The return value will be negative if dy was negative and scrolling proceeeded in that direction.`Math.abs(result)`may be less than dy if a boundary was reached.
|
### setAutoMeasureEnabled
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void setAutoMeasureEnabled (boolean enabled)
```
**This method was deprecated in API level 27.1.0.**
Implementors of LayoutManager should define whether or not it uses AutoMeasure by overriding[isAutoMeasureEnabled()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isAutoMeasureEnabled()).
Defines whether the measuring pass of layout should use the AutoMeasure mechanism of[RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)or if it should be done by the LayoutManager's implementation of[onMeasure(Recycler, State, int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onMeasure(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State, int, int)).
| Parameters ||
|-----------|------------------------------------------------------------------------------------------------------------------------------------|
| `enabled` | `boolean`:`True`if layout measurement should be done by the RecyclerView,`false`if it should be done by this LayoutManager.
|
**See also:**
- [isAutoMeasureEnabled()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isAutoMeasureEnabled())
### setItemPrefetchEnabled
added in[version 25.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void setItemPrefetchEnabled (boolean enabled)
```
Sets whether the LayoutManager should be queried for views outside of its viewport while the UI thread is idle between frames.
If enabled, the LayoutManager will be queried for items to inflate/bind in between view system traversals on devices running API 21 or greater. Default value is true.
On platforms API level 21 and higher, the UI thread is idle between passing a frame to RenderThread and the starting up its next frame at the next VSync pulse. By prefetching out of window views in this time period, delays from inflation and view binding are much less likely to cause jank and stuttering during scrolls and flings.
While prefetch is enabled, it will have the side effect of expanding the effective size of the View cache to hold prefetched views.
| Parameters ||
|-----------|-----------------------------------------------------------------------------|
| `enabled` | `boolean`:`True`if items should be prefetched in between traversals.
|
**See also:**
- [isItemPrefetchEnabled()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isItemPrefetchEnabled())
### setMeasuredDimension
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void setMeasuredDimension (int widthSize,
int heightSize)
```
[Set the measured dimensions](https://developer.android.com/reference/android/view/View.html#setMeasuredDimension(int, int))of the host RecyclerView.
| Parameters ||
|--------------|-------------------------------|
| `widthSize` | `int`: Measured width
|
| `heightSize` | `int`: Measured height
|
### setMeasuredDimension
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void setMeasuredDimension (Rect childrenBounds,
int wSpec,
int hSpec)
```
Sets the measured dimensions from the given bounding box of the children and the measurement specs that were passed into[onMeasure(int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#onMeasure(int, int)). It is only called if a LayoutManager returns`true`from[isAutoMeasureEnabled()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isAutoMeasureEnabled())and it is called after the RecyclerView calls[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State))in the execution of[onMeasure(int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#onMeasure(int, int)).
This method must call[setMeasuredDimension(int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setMeasuredDimension(int, int)).
The default implementation adds the RecyclerView's padding to the given bounding box then caps the value to be within the given measurement specs.
| Parameters ||
|------------------|----------------------------------------------------------------------------|
| `childrenBounds` | `Rect`: The bounding box of all children
|
| `wSpec` | `int`: The widthMeasureSpec that was passed into the RecyclerView.
|
| `hSpec` | `int`: The heightMeasureSpec that was passed into the RecyclerView.
|
**See also:**
- [isAutoMeasureEnabled()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isAutoMeasureEnabled())
- [setMeasuredDimension(int, int)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#setMeasuredDimension(int, int))
### setMeasurementCacheEnabled
added in[version 24.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void setMeasurementCacheEnabled (boolean measurementCacheEnabled)
```
Sets whether RecyclerView should use its own measurement cache for the children. This is a more aggressive cache than the framework uses.
| Parameters ||
|---------------------------|--------------------------------------------------------------------------|
| `measurementCacheEnabled` | `boolean`: True to enable the measurement cache, false otherwise.
|
**See also:**
- [isMeasurementCacheEnabled()](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#isMeasurementCacheEnabled())
### smoothScrollToPosition
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void smoothScrollToPosition (RecyclerView recyclerView,
RecyclerView.State state,
int position)
```
Smooth scroll to the specified adapter position.
To support smooth scrolling, override this method, create your[RecyclerView.SmoothScroller](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.SmoothScroller)instance and call[startSmoothScroll(SmoothScroller)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#startSmoothScroll(android.support.v7.widget.RecyclerView.SmoothScroller)).
| Parameters ||
|----------------|----------------------------------------------------------------------------------|
| `recyclerView` | `RecyclerView`: The RecyclerView to which this layout manager is attached
|
| `state` | `RecyclerView.State`: Current State of RecyclerView
|
| `position` | `int`: Scroll to this adapter position.
|
### startSmoothScroll
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void startSmoothScroll (RecyclerView.SmoothScroller smoothScroller)
```
Starts a smooth scroll using the provided SmoothScroller.
Calling this method will cancel any previous smooth scroll request.
| Parameters ||
|------------------|---------------------------------------------------------------------------------------------------|
| `smoothScroller` | `RecyclerView.SmoothScroller`: Instance which defines how smooth scroll should be animated
|
### stopIgnoringView
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
void stopIgnoringView (View view)
```
View can be scrapped and recycled again.
Note that calling this method removes all information in the view holder.
You can call this method only if your LayoutManger is in onLayout or onScroll callback.
| Parameters ||
|--------|--------------------------------|
| `view` | `View`: View to ignore.
|
### supportsPredictiveItemAnimations
added in[version 22.1.0](https://developer.android.com/topic/libraries/support-library/revisions)
```
boolean supportsPredictiveItemAnimations ()
```
Returns whether this LayoutManager supports "predictive item animations".
"Predictive item animations" are automatically created animations that show where items came from, and where they are going to, as items are added, removed, or moved within a layout.
A LayoutManager wishing to support predictive item animations must override this method to return true (the default implementation returns false) and must obey certain behavioral contracts outlined in[onLayoutChildren(Recycler, State)](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager#onLayoutChildren(android.support.v7.widget.RecyclerView.Recycler, android.support.v7.widget.RecyclerView.State)).
Whether item animations actually occur in a RecyclerView is actually determined by both the return value from this method and the[ItemAnimator](https://developer.android.com/reference/android/support/v7/widget/RecyclerView#setItemAnimator(android.support.v7.widget.RecyclerView.ItemAnimator))set on the RecyclerView itself. If the RecyclerView has a non-null ItemAnimator but this method returns false, then only "simple item animations" will be enabled in the RecyclerView, in which views whose position are changing are simply faded in/out. If the RecyclerView has a non-null ItemAnimator and this method returns true, then predictive item animations will be enabled in the RecyclerView.
| Returns ||
|-----------|-----------------------------------------------------------------------------------------|
| `boolean` | true if this LayoutManager supports predictive item animations, false otherwise.
|
-
## Annotations
- [RecyclerView.EdgeEffectFactory.EdgeDirection](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.EdgeEffectFactory.EdgeDirection)
- [RecyclerView.ItemAnimator.AdapterChanges](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemAnimator.AdapterChanges)
-
## Interfaces
- [ActionMenuView.OnMenuItemClickListener](https://developer.android.com/reference/android/support/v7/widget/ActionMenuView.OnMenuItemClickListener)
- [PopupMenu.OnDismissListener](https://developer.android.com/reference/android/support/v7/widget/PopupMenu.OnDismissListener)
- [PopupMenu.OnMenuItemClickListener](https://developer.android.com/reference/android/support/v7/widget/PopupMenu.OnMenuItemClickListener)
- [RecyclerView.ChildDrawingOrderCallback](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ChildDrawingOrderCallback)
- [RecyclerView.ItemAnimator.ItemAnimatorFinishedListener](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemAnimator.ItemAnimatorFinishedListener)
- [RecyclerView.LayoutManager.LayoutPrefetchRegistry](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager.LayoutPrefetchRegistry)
- [RecyclerView.OnChildAttachStateChangeListener](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.OnChildAttachStateChangeListener)
- [RecyclerView.OnItemTouchListener](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.OnItemTouchListener)
- [RecyclerView.RecyclerListener](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.RecyclerListener)
- [RecyclerView.SmoothScroller.ScrollVectorProvider](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.SmoothScroller.ScrollVectorProvider)
- [SearchView.OnCloseListener](https://developer.android.com/reference/android/support/v7/widget/SearchView.OnCloseListener)
- [SearchView.OnQueryTextListener](https://developer.android.com/reference/android/support/v7/widget/SearchView.OnQueryTextListener)
- [SearchView.OnSuggestionListener](https://developer.android.com/reference/android/support/v7/widget/SearchView.OnSuggestionListener)
- [ShareActionProvider.OnShareTargetSelectedListener](https://developer.android.com/reference/android/support/v7/widget/ShareActionProvider.OnShareTargetSelectedListener)
- [ThemedSpinnerAdapter](https://developer.android.com/reference/android/support/v7/widget/ThemedSpinnerAdapter)
- [Toolbar.OnMenuItemClickListener](https://developer.android.com/reference/android/support/v7/widget/Toolbar.OnMenuItemClickListener)
-
## Classes
- [ActionMenuView](https://developer.android.com/reference/android/support/v7/widget/ActionMenuView)
- [ActionMenuView.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/ActionMenuView.LayoutParams)
- [AppCompatAutoCompleteTextView](https://developer.android.com/reference/android/support/v7/widget/AppCompatAutoCompleteTextView)
- [AppCompatButton](https://developer.android.com/reference/android/support/v7/widget/AppCompatButton)
- [AppCompatCheckBox](https://developer.android.com/reference/android/support/v7/widget/AppCompatCheckBox)
- [AppCompatCheckedTextView](https://developer.android.com/reference/android/support/v7/widget/AppCompatCheckedTextView)
- [AppCompatEditText](https://developer.android.com/reference/android/support/v7/widget/AppCompatEditText)
- [AppCompatImageButton](https://developer.android.com/reference/android/support/v7/widget/AppCompatImageButton)
- [AppCompatImageView](https://developer.android.com/reference/android/support/v7/widget/AppCompatImageView)
- [AppCompatMultiAutoCompleteTextView](https://developer.android.com/reference/android/support/v7/widget/AppCompatMultiAutoCompleteTextView)
- [AppCompatRadioButton](https://developer.android.com/reference/android/support/v7/widget/AppCompatRadioButton)
- [AppCompatRatingBar](https://developer.android.com/reference/android/support/v7/widget/AppCompatRatingBar)
- [AppCompatSeekBar](https://developer.android.com/reference/android/support/v7/widget/AppCompatSeekBar)
- [AppCompatSpinner](https://developer.android.com/reference/android/support/v7/widget/AppCompatSpinner)
- [AppCompatTextView](https://developer.android.com/reference/android/support/v7/widget/AppCompatTextView)
- [CardView](https://developer.android.com/reference/android/support/v7/widget/CardView)
- [DefaultItemAnimator](https://developer.android.com/reference/android/support/v7/widget/DefaultItemAnimator)
- [DividerItemDecoration](https://developer.android.com/reference/android/support/v7/widget/DividerItemDecoration)
- [GridLayout](https://developer.android.com/reference/android/support/v7/widget/GridLayout)
- [GridLayout.Alignment](https://developer.android.com/reference/android/support/v7/widget/GridLayout.Alignment)
- [GridLayout.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/GridLayout.LayoutParams)
- [GridLayout.Spec](https://developer.android.com/reference/android/support/v7/widget/GridLayout.Spec)
- [GridLayoutManager](https://developer.android.com/reference/android/support/v7/widget/GridLayoutManager)
- [GridLayoutManager.DefaultSpanSizeLookup](https://developer.android.com/reference/android/support/v7/widget/GridLayoutManager.DefaultSpanSizeLookup)
- [GridLayoutManager.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/GridLayoutManager.LayoutParams)
- [GridLayoutManager.SpanSizeLookup](https://developer.android.com/reference/android/support/v7/widget/GridLayoutManager.SpanSizeLookup)
- [LinearLayoutCompat](https://developer.android.com/reference/android/support/v7/widget/LinearLayoutCompat)
- [LinearLayoutCompat.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/LinearLayoutCompat.LayoutParams)
- [LinearLayoutManager](https://developer.android.com/reference/android/support/v7/widget/LinearLayoutManager)
- [LinearLayoutManager.LayoutChunkResult](https://developer.android.com/reference/android/support/v7/widget/LinearLayoutManager.LayoutChunkResult)
- [LinearSmoothScroller](https://developer.android.com/reference/android/support/v7/widget/LinearSmoothScroller)
- [LinearSnapHelper](https://developer.android.com/reference/android/support/v7/widget/LinearSnapHelper)
- [ListPopupWindow](https://developer.android.com/reference/android/support/v7/widget/ListPopupWindow)
- [OrientationHelper](https://developer.android.com/reference/android/support/v7/widget/OrientationHelper)
- [PagerSnapHelper](https://developer.android.com/reference/android/support/v7/widget/PagerSnapHelper)
- [PopupMenu](https://developer.android.com/reference/android/support/v7/widget/PopupMenu)
- [RecyclerView](https://developer.android.com/reference/android/support/v7/widget/RecyclerView)
- [RecyclerView.Adapter](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Adapter)
- [RecyclerView.AdapterDataObserver](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.AdapterDataObserver)
- [RecyclerView.EdgeEffectFactory](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.EdgeEffectFactory)
- [RecyclerView.ItemAnimator](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemAnimator)
- [RecyclerView.ItemAnimator.ItemHolderInfo](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemAnimator.ItemHolderInfo)
- [RecyclerView.ItemDecoration](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ItemDecoration)
- [RecyclerView.LayoutManager](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager)
- [RecyclerView.LayoutManager.Properties](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutManager.Properties)
- [RecyclerView.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.LayoutParams)
- [RecyclerView.OnFlingListener](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.OnFlingListener)
- [RecyclerView.OnScrollListener](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.OnScrollListener)
- [RecyclerView.RecycledViewPool](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.RecycledViewPool)
- [RecyclerView.Recycler](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.Recycler)
- [RecyclerView.SimpleOnItemTouchListener](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.SimpleOnItemTouchListener)
- [RecyclerView.SmoothScroller](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.SmoothScroller)
- [RecyclerView.SmoothScroller.Action](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.SmoothScroller.Action)
- [RecyclerView.State](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.State)
- [RecyclerView.ViewCacheExtension](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ViewCacheExtension)
- [RecyclerView.ViewHolder](https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ViewHolder)
- [RecyclerViewAccessibilityDelegate](https://developer.android.com/reference/android/support/v7/widget/RecyclerViewAccessibilityDelegate)
- [RecyclerViewAccessibilityDelegate.ItemDelegate](https://developer.android.com/reference/android/support/v7/widget/RecyclerViewAccessibilityDelegate.ItemDelegate)
- [SearchView](https://developer.android.com/reference/android/support/v7/widget/SearchView)
- [ShareActionProvider](https://developer.android.com/reference/android/support/v7/widget/ShareActionProvider)
- [SimpleItemAnimator](https://developer.android.com/reference/android/support/v7/widget/SimpleItemAnimator)
- [SnapHelper](https://developer.android.com/reference/android/support/v7/widget/SnapHelper)
- [StaggeredGridLayoutManager](https://developer.android.com/reference/android/support/v7/widget/StaggeredGridLayoutManager)
- [StaggeredGridLayoutManager.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/StaggeredGridLayoutManager.LayoutParams)
- [SwitchCompat](https://developer.android.com/reference/android/support/v7/widget/SwitchCompat)
- [ThemedSpinnerAdapter.Helper](https://developer.android.com/reference/android/support/v7/widget/ThemedSpinnerAdapter.Helper)
- [Toolbar](https://developer.android.com/reference/android/support/v7/widget/Toolbar)
- [Toolbar.LayoutParams](https://developer.android.com/reference/android/support/v7/widget/Toolbar.LayoutParams)
- [Toolbar.SavedState](https://developer.android.com/reference/android/support/v7/widget/Toolbar.SavedState)
- [TooltipCompat](https://developer.android.com/reference/android/support/v7/widget/TooltipCompat)