RecyclerView

public class RecyclerView extends ViewGroup implements ScrollingView, NestedScrollingChild2, NestedScrollingChild3

Known direct subclasses
BaseGridView

An abstract base class for vertically and horizontally scrolling lists.

WearableRecyclerView

Wearable specific implementation of the RecyclerView enabling setCircularScrollingGestureEnabled circular scrolling} and semi-circular layouts.

Known indirect subclasses
HorizontalGridView

A android.view.ViewGroup that shows items in a horizontal scrolling list.

VerticalGridView

A android.view.ViewGroup that shows items in a vertically scrolling list.


A flexible view for providing a limited window into a large data set.

Glossary of terms:

  • Adapter: A subclass of Adapter responsible for providing views that represent items in a data set.
  • Position: The position of a data item within an Adapter.
  • Index: The index of an attached child view as used in a call to getChildAt. Contrast with Position.
  • Binding: The process of preparing a child view to display data corresponding to a position within the adapter.
  • Recycle (view): A view previously used to display data for a specific adapter position may be placed in a cache for later reuse to display the same type of data again later. This can drastically improve performance by skipping initial layout inflation or construction.
  • Scrap (view): A child view that has entered into a temporarily detached state during layout. Scrap views may be reused without becoming fully detached from the parent RecyclerView, either unmodified if no rebinding is required or modified by the adapter if the view was considered dirty.
  • Dirty (view): A child view that must be rebound by the adapter before being displayed.

Positions in RecyclerView:

RecyclerView introduces an additional level of abstraction between the Adapter and LayoutManager to be able to detect data set changes in batches during a layout calculation. This saves LayoutManager from tracking adapter changes to calculate animations. It also helps with performance because all view bindings happen at the same time and unnecessary bindings are avoided.

For this reason, there are two types of position related methods in RecyclerView:

  • layout position: Position of an item in the latest layout calculation. This is the position from the LayoutManager's perspective.
  • adapter position: Position of an item in the adapter. This is the position from the Adapter's perspective.

These two positions are the same except the time between dispatching adapter.notify* events and calculating the updated layout.

Methods that return or receive *LayoutPosition* use position as of the latest layout calculation (e.g. getLayoutPosition, findViewHolderForLayoutPosition). These positions include all changes until the last layout calculation. You can rely on these positions to be consistent with what user is currently seeing on the screen. For example, if you have a list of items on the screen and user asks for the 5th element, you should use these methods as they'll match what user is seeing.

The other set of position related methods are in the form of *AdapterPosition*. (e.g. getAbsoluteAdapterPosition, getBindingAdapterPosition, findViewHolderForAdapterPosition) You should use these methods when you need to work with up-to-date adapter positions even if they may not have been reflected to layout yet. For example, if you want to access the item in the adapter on a ViewHolder click, you should use getBindingAdapterPosition. Beware that these methods may not be able to calculate adapter positions if notifyDataSetChanged has been called and new layout has not yet been calculated. For this reasons, you should carefully handle NO_POSITION or null results from these methods.

When writing a LayoutManager you almost always want to use layout positions whereas when writing an Adapter, you probably want to use adapter positions.

Presenting Dynamic Data

To display updatable data in a RecyclerView, your adapter needs to signal inserts, moves, and deletions to RecyclerView. You can build this yourself by manually calling adapter.notify* methods when content changes, or you can use one of the easier solutions RecyclerView provides: List diffing with DiffUtil If your RecyclerView is displaying a list that is re-fetched from scratch for each update (e.g. from the network, or from a database), DiffUtil can calculate the difference between versions of the list. DiffUtil takes both lists as input and computes the difference, which can be passed to RecyclerView to trigger minimal animations and updates to keep your UI performant, and animations meaningful. This approach requires that each list is represented in memory with immutable content, and relies on receiving updates as new instances of lists. This approach is also ideal if your UI layer doesn't implement sorting, it just presents the data in the order it's given.

The best part of this approach is that it extends to any arbitrary changes - item updates, moves, addition and removal can all be computed and handled the same way. Though you do have to keep two copies of the list in memory while diffing, and must avoid mutating them, it's possible to share unmodified elements between list versions.

There are three primary ways to do this for RecyclerView. We recommend you start with ListAdapter, the higher-level API that builds in List diffing on a background thread, with minimal code. AsyncListDiffer also provides this behavior, but without defining an Adapter to subclass. If you want more control, DiffUtil is the lower-level API you can use to compute the diffs yourself. Each approach allows you to specify how diffs should be computed based on item data.

List mutation with SortedList If your RecyclerView receives updates incrementally, e.g. item X is inserted, or item Y is removed, you can use SortedList to manage your list. You define how to order items, and it will automatically trigger update signals that RecyclerView can use. SortedList works if you only need to handle insert and remove events, and has the benefit that you only ever need to have a single copy of the list in memory. It can also compute differences with replaceAll, but this method is more limited than the list diffing behavior above. Paging Library The Paging library extends the diff-based approach to additionally support paged loading. It provides the androidx.paging.PagedList class that operates as a self-loading list, provided a source of data like a database, or paginated network API. It provides convenient list diffing support out of the box, similar to ListAdapter and AsyncListDiffer. For more information about the Paging library, see the library documentation. layoutManager

Summary

Nested types

public abstract class RecyclerView.Adapter<VH extends RecyclerView.ViewHolder>

Base class for an Adapter

Defines how this Adapter wants to restore its state after a view reconstruction (e.g. configuration change).

public abstract class RecyclerView.AdapterDataObserver

Observer base class for watching changes to an Adapter.

A callback interface that can be used to alter the drawing order of RecyclerView children.

EdgeEffectFactory lets you customize the over-scroll edge effect for RecyclerViews.

@Retention(value = RetentionPolicy.SOURCE)
@IntDef(value = )
public annotation RecyclerView.EdgeEffectFactory.EdgeDirection
public abstract class RecyclerView.ItemAnimator

This class defines the animations that take place on items as changes are made to the adapter.

@IntDef(flag = true, value = )
@Retention(value = RetentionPolicy.SOURCE)
public annotation RecyclerView.ItemAnimator.AdapterChanges

The set of flags that might be passed to recordPreLayoutInformation.

This interface is used to inform listeners when all pending or running animations in an ItemAnimator are finished.

A simple data structure that holds information about an item's bounds.

public abstract class RecyclerView.ItemDecoration

An ItemDecoration allows the application to add a special drawing and layout offset to specific item views from the adapter's data set.

public abstract class RecyclerView.LayoutManager

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.

Interface for LayoutManagers to request items to be prefetched, based on position, with specified distance from viewport, which indicates priority.

Some general properties that a LayoutManager may want to use.

LayoutParams subclass for children of RecyclerView.

A Listener interface that can be attached to a RecylcerView to get notified whenever a ViewHolder is attached to or detached from RecyclerView.

public abstract class RecyclerView.OnFlingListener

This class defines the behavior of fling if the developer wishes to handle it.

An OnItemTouchListener allows the application to intercept touch events in progress at the view hierarchy level of the RecyclerView before those touch events are considered for RecyclerView's own scrolling behavior.

public abstract class RecyclerView.OnScrollListener

An OnScrollListener can be added to a RecyclerView to receive messages when a scrolling event has occurred on that RecyclerView.

RecycledViewPool lets you share Views between multiple RecyclerViews.

public final class RecyclerView.Recycler

A Recycler is responsible for managing scrapped or detached item views for reuse.

A RecyclerListener can be set on a RecyclerView to receive messages whenever a view is recycled.

An implementation of RecyclerView.OnItemTouchListener that has empty method bodies and default return values.

public abstract class RecyclerView.SmoothScroller

Base class for smooth scrolling.

Holds information about a smooth scroll request by a SmoothScroller.

An interface which is optionally implemented by custom RecyclerView.LayoutManager to provide a hint to a SmoothScroller about the location of the target position.

public class RecyclerView.State

Contains useful information about the current RecyclerView state like target scroll position or view focus.

public abstract class RecyclerView.ViewCacheExtension

ViewCacheExtension is a helper class to provide an additional layer of view caching that can be controlled by the developer.

public abstract class RecyclerView.ViewHolder

A ViewHolder describes an item view and metadata about its place within the RecyclerView.

Constants

static final int
static final int
static final long
NO_ID = -1
static final int
static final int

The RecyclerView is currently being dragged by outside input such as user touch input.

static final int

The RecyclerView is not currently scrolling.

static final int

The RecyclerView is currently animating to a final position while not under outside control.

static final int

Constant for use with setScrollingTouchSlop.

static final int

Constant for use with setScrollingTouchSlop.

static final int
UNDEFINED_DURATION = -2147483648

Constant that represents that a duration has not been defined.

static final int

Public constructors

RecyclerView(
    @NonNull Context context,
    @Nullable AttributeSet attrs,
    int defStyleAttr
)

Public methods

void
addFocusables(ArrayList<View> views, int direction, int focusableMode)
void

Add an ItemDecoration to this RecyclerView.

void

Add an ItemDecoration to this RecyclerView.

void

Register a listener that will be notified whenever a child view is attached to or detached from RecyclerView.

void

Add an OnItemTouchListener to intercept touch events before they are dispatched to child views or this view's standard scrolling behavior.

void

Add a listener that will be notified of any changes in scroll state or position.

void

Register a listener that will be notified whenever a child view is recycled.

void

Removes all listeners that were added via addOnChildAttachStateChangeListener.

void

Remove all secondary listener that were notified of any changes in scroll state or position.

int

Compute the horizontal extent of the horizontal scrollbar's thumb within the horizontal range.

int

Compute the horizontal offset of the horizontal scrollbar's thumb within the horizontal range.

int

Compute the horizontal range that the horizontal scrollbar represents.

int

Compute the vertical extent of the vertical scrollbar's thumb within the vertical range.

int

Compute the vertical offset of the vertical scrollbar's thumb within the vertical range.

int

Compute the vertical range that the vertical scrollbar represents.

boolean
boolean
dispatchNestedFling(float velocityX, float velocityY, boolean consumed)
boolean
dispatchNestedPreFling(float velocityX, float velocityY)
boolean
dispatchNestedPreScroll(
    int dx,
    int dy,
    int[] consumed,
    int[] offsetInWindow
)
boolean
dispatchNestedPreScroll(
    int dx,
    int dy,
    int[] consumed,
    int[] offsetInWindow,
    int type
)

Dispatch one step of a nested scroll in progress before this view consumes any portion of it.

boolean
dispatchNestedScroll(
    int dxConsumed,
    int dyConsumed,
    int dxUnconsumed,
    int dyUnconsumed,
    int[] offsetInWindow
)
boolean
dispatchNestedScroll(
    int dxConsumed,
    int dyConsumed,
    int dxUnconsumed,
    int dyUnconsumed,
    int[] offsetInWindow,
    int type
)

Dispatch one step of a nested scroll in progress.

final void
dispatchNestedScroll(
    int dxConsumed,
    int dyConsumed,
    int dxUnconsumed,
    int dyUnconsumed,
    int[] offsetInWindow,
    int type,
    @NonNull int[] consumed
)

Dispatch one step of a nested scroll in progress.

boolean
void
boolean
drawChild(@NonNull Canvas canvas, View child, long drawingTime)
@Nullable View
findChildViewUnder(float x, float y)

Find the topmost view under the given point.

@Nullable View

Traverses the ancestors of the given view and returns the item view that contains it and also a direct child of the RecyclerView.

@Nullable RecyclerView.ViewHolder

Returns the ViewHolder that contains the given view.

@Nullable RecyclerView.ViewHolder

Return the ViewHolder for the item in the given position of the data set.

RecyclerView.ViewHolder

Return the ViewHolder for the item with the given id.

@Nullable RecyclerView.ViewHolder

Return the ViewHolder for the item in the given position of the data set as of the latest layout pass.

@Nullable RecyclerView.ViewHolder

This method is deprecated.

use findViewHolderForLayoutPosition or findViewHolderForAdapterPosition

boolean
fling(int velocityX, int velocityY)

Begin a standard fling with an initial velocity along each axis in pixels per second.

View
focusSearch(View focused, int direction)

Since RecyclerView is a collection ViewGroup that includes virtual children (items that are in the Adapter but not visible in the UI), it employs a more involved focus search strategy that differs from other ViewGroups.

ViewGroup.LayoutParams
CharSequence
@Nullable RecyclerView.Adapter

Retrieves the previously set adapter or null if no adapter is set.

int

Return the offset of the RecyclerView's text baseline from the its top boundary.

int

Return the adapter position that the given child view corresponds to.

long

Return the stable item id that the given child view corresponds to.

int

Return the adapter position of the given child view as of the latest completed layout pass.

int

This method is deprecated.

use getChildAdapterPosition or getChildLayoutPosition.

RecyclerView.ViewHolder

Retrieve the ViewHolder for the given child view.

boolean

Returns whether this RecyclerView will clip its children to its padding, and resize (but not clip) any EdgeEffect to the padded region, if padding is present.

@Nullable RecyclerViewAccessibilityDelegate

Returns the accessibility delegate compatibility implementation used by the RecyclerView.

void

Returns the bounds of the view including its decoration and margins.

@NonNull RecyclerView.EdgeEffectFactory

Retrieves the previously set EdgeEffectFactory or the default factory if nothing was set.

@Nullable RecyclerView.ItemAnimator

Gets the current ItemAnimator for this RecyclerView.

@NonNull RecyclerView.ItemDecoration

Returns an ItemDecoration previously added to this RecyclerView.

int

Returns the number of ItemDecoration currently added to this RecyclerView.

@Nullable RecyclerView.LayoutManager

Return the LayoutManager currently responsible for layout policy for this RecyclerView.

int

Returns the maximum fling velocity used by this RecyclerView.

int

Returns the minimum velocity to start a fling.

@Nullable RecyclerView.OnFlingListener

Get the current OnFlingListener from this RecyclerView.

boolean

Returns true if the RecyclerView should attempt to preserve currently focused Adapter Item's focus even if the View representing the Item is replaced during a layout calculation.

@NonNull RecyclerView.RecycledViewPool

Retrieve this RecyclerView's RecycledViewPool.

int

Return the current scrolling state of the RecyclerView.

boolean
boolean
boolean

Returns true if this view has a nested scrolling parent for the given input type.

boolean

Returns whether there are pending adapter updates which are not yet applied to the layout.

void

Invalidates all ItemDecorations.

boolean

Returns true if RecyclerView is currently running some animations.

boolean

Returns true if RecyclerView is attached to window.

boolean

Returns whether RecyclerView is currently computing a layout.

boolean

This method is deprecated.

Use isLayoutSuppressed.

final boolean

Returns whether layout and scroll calls on this container are currently being suppressed, due to an earlier call to suppressLayout.

boolean
void
nestedScrollBy(int x, int y)

Same as scrollBy, but also participates in nested scrolling.

void

Offset the bounds of all child views by dx pixels.

void

Offset the bounds of all child views by dy pixels.

void

Called when an item view is attached to this RecyclerView.

void

Called when an item view is detached from this RecyclerView.

void
boolean
boolean
void

Called when the scroll state of this RecyclerView changes.

void
onScrolled(@Px int dx, @Px int dy)

Called when the scroll position of this RecyclerView changes.

boolean
void

Remove an ItemDecoration from this RecyclerView.

void

Removes the ItemDecoration associated with the supplied index position.

void

Removes the provided listener from child attached state listeners list.

void

Remove an OnItemTouchListener.

void

Remove a listener that was notified of any changes in scroll state or position.

void

Removes the provided listener from RecyclerListener list.

void
requestChildFocus(View child, View focused)
boolean
requestChildRectangleOnScreen(View child, Rect rect, boolean immediate)
void
requestDisallowInterceptTouchEvent(boolean disallowIntercept)
void
void
scrollBy(int x, int y)
void
scrollTo(int x, int y)
void
scrollToPosition(int position)

Convenience method to scroll to a certain position.

void
void

Sets the accessibility delegate compatibility implementation used by RecyclerView.

void

Set a new adapter to provide child views on demand.

void

Sets the ChildDrawingOrderCallback to be used for drawing children.

void
setClipToPadding(boolean clipToPadding)
static void
setDebugAssertionsEnabled(boolean debugAssertionsEnabled)

Enable internal assertions about RecyclerView's state and throw exceptions if the assertions are violated.

void

Set a EdgeEffectFactory for this RecyclerView.

void
setHasFixedSize(boolean hasFixedSize)

RecyclerView can perform several optimizations if it can know in advance that RecyclerView's size is not affected by the adapter contents.

void

Sets the ItemAnimator that will handle animations involving changes to the items in this RecyclerView.

void

Set the number of offscreen views to retain before adding them to the potentially shared recycled view pool.

void
setLayoutFrozen(boolean frozen)

This method is deprecated.

Use suppressLayout.

void

Set the LayoutManager that this RecyclerView will use.

void

This method is deprecated.

Use setItemAnimator ()}.

void
setNestedScrollingEnabled(boolean enabled)
void

Set a OnFlingListener for this RecyclerView.

void

This method is deprecated.

Use addOnScrollListener and removeOnScrollListener

void
setPreserveFocusAfterLayout(boolean preserveFocusAfterLayout)

Set whether the RecyclerView should try to keep the same Item focused after a layout calculation or not.

void

Recycled view pools allow multiple RecyclerViews to share a common pool of scrap views.

void

This method is deprecated.

Use addRecyclerListener and removeRecyclerListener

void
setScrollingTouchSlop(int slopConstant)

Configure the scrolling touch slop for a specific use case.

static void
setVerboseLoggingEnabled(boolean verboseLoggingEnabled)

Enable verbose logging within RecyclerView itself.

void

Sets a new ViewCacheExtension to be used by the Recycler.

void
smoothScrollBy(@Px int dx, @Px int dy)

Animate a scroll by the given amount of pixels along either axis.

void
smoothScrollBy(@Px int dx, @Px int dy, @Nullable Interpolator interpolator)

Animate a scroll by the given amount of pixels along either axis.

void
smoothScrollBy(
    @Px int dx,
    @Px int dy,
    @Nullable Interpolator interpolator,
    int duration
)

Smooth scrolls the RecyclerView by a given distance.

void
smoothScrollToPosition(int position)

Starts a smooth scroll to an adapter position.

boolean
boolean
startNestedScroll(int axes, int type)

Begin a nestable scroll operation along the given axes, for the given input type.

void
void
stopNestedScroll(int type)

Stop a nested scroll in progress for the given input type.

void

Stop any current scroll in progress, such as one started by smoothScrollBy, fling or a touch-initiated fling.

final void
suppressLayout(boolean suppress)

Tells this RecyclerView to suppress all layout and scroll calls until layout suppression is disabled with a later call to suppressLayout(false).

void
swapAdapter(
    @Nullable RecyclerView.Adapter adapter,
    boolean removeAndRecycleExistingViews
)

Swaps the current adapter with the provided one.

Protected methods

boolean
void

Override to prevent thawing of any views created by the adapter.

void

Override to prevent freezing of any views created by the adapter.

ViewGroup.LayoutParams
ViewGroup.LayoutParams
int
getChildDrawingOrder(int childCount, int i)
void
void
void
onLayout(boolean changed, int l, int t, int r, int b)
void
onMeasure(int widthSpec, int heightSpec)
boolean
onRequestFocusInDescendants(int direction, Rect previouslyFocusedRect)
void
Parcelable
void
onSizeChanged(int w, int h, int oldw, int oldh)
void
removeDetachedView(View child, boolean animate)

Inherited Constants

From android.view.View
static final int
static final int
static final int
static final int
static final int
static final int
static final Property<ViewFloat>
static final int
static final String
AUTOFILL_HINT_CREDIT_CARD_EXPIRATION_DATE = "creditCardExpirationDate"
static final String
AUTOFILL_HINT_CREDIT_CARD_EXPIRATION_DAY = "creditCardExpirationDay"
static final String
AUTOFILL_HINT_CREDIT_CARD_EXPIRATION_MONTH = "creditCardExpirationMonth"
static final String
AUTOFILL_HINT_CREDIT_CARD_EXPIRATION_YEAR = "creditCardExpirationYear"
static final String
static final String
AUTOFILL_HINT_CREDIT_CARD_SECURITY_CODE = "creditCardSecurityCode"
static final String
static final String
static final String
static final String
static final String
static final String
static final String
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int

This field is deprecated.

static final int

This field is deprecated.

static final int

This field is deprecated.

static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int
static final int
static final int
static final int
static final int
static final int
static final int[]
static final int[]
static final int[]
static final int[]
static final int
static final int
static final int
static final int
static final int
static final int
static final int
GONE = 8
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
KEEP_SCREEN_ON = 67108864
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
NO_ID = -1
static final int
static final int
static final int
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final int[]
static final Property<ViewFloat>
static final Property<ViewFloat>
static final Property<ViewFloat>
static final Property<ViewFloat>
static final Property<ViewFloat>
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int[]
static final int[]
static final int
static final int

This field is deprecated.

static final int

This field is deprecated.

static final int

This field is deprecated.

static final int

This field is deprecated.

static final int

This field is deprecated.

static final int

This field is deprecated.

static final int

This field is deprecated.

static final int

This field is deprecated.

static final int

This field is deprecated.

static final int

This field is deprecated.

static final int

This field is deprecated.

static final int

This field is deprecated.

static final int

This field is deprecated.

static final int

This field is deprecated.

static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final int
static final Property<ViewFloat>
static final Property<ViewFloat>
static final Property<ViewFloat>
static final String
VIEW_LOG_TAG = "View"
static final int
static final int[]
static final Property<ViewFloat>
static final Property<ViewFloat>
static final Property<ViewFloat>
From android.view.ViewGroup
static final int
static final int
static final int
static final int
static final int
static final int
static final int

This field is deprecated.

static final int

This field is deprecated.

static final int

This field is deprecated.

static final int

This field is deprecated.

Inherited methods

From android.view.View
void
void
void
ViewPropertyAnimator
void
void
boolean
void
void

This method is deprecated.

void
boolean
boolean
boolean
boolean
boolean
canScrollHorizontally(int direction)
boolean
canScrollVertically(int direction)
final void
void
final void
boolean
void
void
static int
combineMeasuredStates(int curState, int newState)
void
WindowInsets
AccessibilityNodeInfo
void
void

This method is deprecated.

boolean
boolean
dispatchNestedPrePerformAccessibilityAction(
    int action,
    Bundle arguments
)
void
drawableHotspotChanged(float x, float y)
final OnBackInvokedDispatcher
final T
<T extends View> findViewById(int id)
final T
<T extends View> findViewWithTag(Object tag)
boolean

This method is deprecated.

void
forceHasOverlappingRendering(boolean hasOverlappingRendering)
void
void
generateDisplayHash(
    String hashAlgorithm,
    Rect bounds,
    Executor executor,
    DisplayHashResultCallback callback
)
static int
View.AccessibilityDelegate
int
AccessibilityNodeProvider
CharSequence
int
int
String
String
float
Animation
Matrix
IBinder
int[]
Map<IntegerInteger>
String[]
final AutofillId
int
AutofillValue
Drawable
BlendMode
ColorStateList
PorterDuff.Mode
final int
float
int
float
Rect
boolean
final boolean
final ContentCaptureSession
CharSequence
final Context
ContextMenu.ContextMenuInfo
final boolean
static int
getDefaultSize(int size, int measureSpec)
Display
final int[]
Bitmap

This method is deprecated.

int

This method is deprecated.

int

This method is deprecated.

void
long
float
int
boolean
boolean
int
ArrayList<View>
getFocusables(int direction)
void
Drawable
int
BlendMode
ColorStateList
PorterDuff.Mode
boolean
getGlobalVisibleRect(Rect r, Point globalOffset)
Handler
float
float
float
float
Runnable
final boolean
final int
void
getHitRect(Rect outRect)
int
int
Drawable
Drawable
int
int
int
int
boolean
KeyEvent.DispatcherState
int
int
int
ViewGroup.LayoutParams
final int
float
int
final boolean
void
getLocationInSurface(int[] location)
void
getLocationInWindow(int[] outLocation)
void
getLocationOnScreen(int[] outLocation)
Matrix
final int
final int
final int
final int
final int
int
int
int
int
int
int
int
int
View.OnFocusChangeListener
int
ViewOutlineProvider
int
int
ViewOverlay
int
int
int
int
int
int
final ViewParent
ViewParent
float
float
PointerIcon
final List<Rect>
String[]
Resources
final boolean
final int
float
int
AttachedSurfaceControl
View
WindowInsets
float
float
float
float
float
int
int
int
int
int
int
final int
final int
int
int
final CharSequence
StateListAnimator
int
int
List<Rect>
int

This method is deprecated.

Object
int
int
CharSequence
final int
float
int
TouchDelegate
ArrayList<View>
float
String
float
float
float
long
int
int
Drawable
Drawable
int
ViewTranslationResponse
ViewTreeObserver
int
final int
int
WindowId
WindowInsetsController
int

This method is deprecated.

IBinder
int
void
float
float
float
boolean
boolean
boolean
boolean
boolean
boolean
boolean
static View
inflate(Context context, int resource, ViewGroup root)
void

This method is deprecated.

void
void
boolean
boolean
boolean
boolean
boolean
boolean
boolean
boolean
boolean
boolean

This method is deprecated.

boolean
boolean
final boolean
final boolean
boolean
final boolean
boolean
boolean
boolean
boolean
boolean
boolean
boolean
boolean
final boolean
final boolean
boolean
boolean
boolean
final boolean
boolean
boolean
boolean
boolean
boolean
boolean
boolean
boolean
final boolean
boolean
boolean
boolean
boolean
boolean
boolean
boolean
final boolean
boolean
boolean
final boolean
boolean
boolean
boolean
boolean
boolean
View
keyboardNavigationClusterSearch(View currentCluster, int direction)
final void
measure(int widthMeasureSpec, int heightMeasureSpec)
static int[]
mergeDrawableStates(int[] baseState, int[] additionalState)
void
offsetLeftAndRight(int offset)
void
offsetTopAndBottom(int offset)
void
void
WindowInsets
void
boolean
boolean
void
void
InputConnection
void
onCreateViewTranslationRequest(
    int[] supportedFormats,
    Consumer<ViewTranslationRequest> requestsCollector
)
void
onCreateVirtualViewTranslationRequests(
    long[] virtualIds,
    int[] supportedFormats,
    Consumer<ViewTranslationRequest> requestsCollector
)
void
onDisplayHint(int hint)
boolean
void
final void
boolean
void
void
void
onFocusChanged(
    boolean gainFocus,
    int direction,
    Rect previouslyFocusedRect
)
void
onHoverChanged(boolean hovered)
boolean
void
void
boolean
onKeyDown(int keyCode, KeyEvent event)
boolean
onKeyLongPress(int keyCode, KeyEvent event)
boolean
onKeyMultiple(int keyCode, int repeatCount, KeyEvent event)
boolean
onKeyPreIme(int keyCode, KeyEvent event)
boolean
onKeyShortcut(int keyCode, KeyEvent event)
boolean
onKeyUp(int keyCode, KeyEvent event)
void
onOverScrolled(
    int scrollX,
    int scrollY,
    boolean clampedX,
    boolean clampedY
)
void
onPointerCaptureChange(boolean hasCapture)
void
void
onProvideAutofillStructure(ViewStructure structure, int flags)
void
void
void
void
ContentInfo
void
onRtlPropertiesChanged(int layoutDirection)
void
onScreenStateChanged(int screenState)
void
onScrollCaptureSearch(
    Rect localVisibleRect,
    Point windowOffset,
    Consumer<ScrollCaptureTarget> targets
)
void
onScrollChanged(int l, int t, int oldl, int oldt)
boolean
onSetAlpha(int alpha)
void
boolean
void
void
void
onVisibilityAggregated(boolean isVisible)
void
onVisibilityChanged(View changedView, int visibility)
void
onWindowFocusChanged(boolean hasWindowFocus)
void

This method is deprecated.

void
onWindowVisibilityChanged(int visibility)
boolean
overScrollBy(
    int deltaX,
    int deltaY,
    int scrollX,
    int scrollY,
    int scrollRangeX,
    int scrollRangeY,
    int maxOverScrollX,
    int maxOverScrollY,
    boolean isTouchEvent
)
boolean
performAccessibilityAction(int action, Bundle arguments)
boolean
boolean
performContextClick(float x, float y)
boolean
performHapticFeedback(int feedbackConstant)
boolean
ContentInfo
void
playSoundEffect(int soundConstant)
boolean
post(Runnable action)
boolean
postDelayed(Runnable action, long delayMillis)
void
void
postInvalidateDelayed(long delayMilliseconds)
void
void
void
postOnAnimationDelayed(Runnable action, long delayMillis)
void
void
boolean
void
void
void
void
void

This method is deprecated.

final boolean
void
boolean
final void
final T
<T extends View> requireViewById(int id)
void
static int
resolveSize(int size, int measureSpec)
static int
resolveSizeAndState(int size, int measureSpec, int childMeasuredState)
void
final void
saveAttributeDataForStyleable(
    Context context,
    int[] styleable,
    AttributeSet attrs,
    TypedArray t,
    int defStyleAttr,
    int defStyleRes
)
void
void
scheduleDrawable(Drawable who, Runnable what, long when)
void
sendAccessibilityEvent(int eventType)
void
setAccessibilityDataSensitive(int accessibilityDataSensitive)
void
void
setAccessibilityHeading(boolean isHeading)
void
void
setAccessibilityPaneTitle(CharSequence accessibilityPaneTitle)
void
void
void
setActivated(boolean activated)
void
setAllowClickWhenDisabled(boolean clickableWhenDisabled)
void
void
void
setAlpha(float alpha)
void
void
void
setAutoHandwritingEnabled(boolean enabled)
void
setAutofillHints(String[] autofillHints)
void
void
setBackground(Drawable background)
void
setBackgroundColor(int color)
void

This method is deprecated.

void
void
void
void
final void
setBottom(int bottom)
void
setCameraDistance(float distance)
void
setClickable(boolean clickable)
void
setClipBounds(Rect clipBounds)
void
setClipToOutline(boolean clipToOutline)
void
void
setContentDescription(CharSequence contentDescription)
void
setContextClickable(boolean contextClickable)
void
setDefaultFocusHighlightEnabled(boolean defaultFocusHighlightEnabled)
void

This method is deprecated.

void
setDrawingCacheEnabled(boolean enabled)

This method is deprecated.

void

This method is deprecated.

void
void
setElevation(float elevation)
void
setEnabled(boolean enabled)
void
setFadingEdgeLength(int length)
void
void
setFitsSystemWindows(boolean fitSystemWindows)
void
setFocusable(boolean focusable)
void
setFocusableInTouchMode(boolean focusableInTouchMode)
void
setFocusedByDefault(boolean isFocusedByDefault)
void
setForceDarkAllowed(boolean allow)
void
setForeground(Drawable foreground)
void
setForegroundGravity(int gravity)
void
void
void
void
setHandwritingBoundsOffsets(
    float offsetLeft,
    float offsetTop,
    float offsetRight,
    float offsetBottom
)
void
void
setHapticFeedbackEnabled(boolean hapticFeedbackEnabled)
void
setHasTransientState(boolean hasTransientState)
void
setHorizontalFadingEdgeEnabled(boolean horizontalFadingEdgeEnabled)
void
setHorizontalScrollBarEnabled(boolean horizontalScrollBarEnabled)
void
void
void
setHovered(boolean hovered)
void
setId(int id)
void
void
void
void
setIsCredential(boolean isCredential)
void
setIsHandwritingDelegate(boolean isHandwritingDelegate)
void
setKeepScreenOn(boolean keepScreenOn)
void
setKeyboardNavigationCluster(boolean isCluster)
void
setLabelFor(int id)
void
void
setLayerType(int layerType, Paint paint)
void
setLayoutDirection(int layoutDirection)
void
final void
setLeft(int left)
final void
setLeftTopRightBottom(int left, int top, int right, int bottom)
void
setLongClickable(boolean longClickable)
final void
setMeasuredDimension(int measuredWidth, int measuredHeight)
void
setMinimumHeight(int minHeight)
void
setMinimumWidth(int minWidth)
void
setNextClusterForwardId(int nextClusterForwardId)
void
setNextFocusDownId(int nextFocusDownId)
void
setNextFocusForwardId(int nextFocusForwardId)
void
setNextFocusLeftId(int nextFocusLeftId)
void
setNextFocusRightId(int nextFocusRightId)
void
setNextFocusUpId(int nextFocusUpId)
void
void
void
void
void
void
void
void
void
void
void
void
setOnReceiveContentListener(
    String[] mimeTypes,
    OnReceiveContentListener listener
)
void
void

This method is deprecated.

void
void
void
void
void
setOverScrollMode(int overScrollMode)
void
setPadding(int left, int top, int right, int bottom)
void
setPaddingRelative(int start, int top, int end, int bottom)
void
setPivotX(float pivotX)
void
setPivotY(float pivotY)
void
final void
setPreferKeepClear(boolean preferKeepClear)
final void
void
setPressed(boolean pressed)
void
final void
setRevealOnFocusHint(boolean revealOnFocus)
final void
setRight(int right)
void
setRotation(float rotation)
void
setRotationX(float rotationX)
void
setRotationY(float rotationY)
void
setSaveEnabled(boolean enabled)
void
setSaveFromParentEnabled(boolean enabled)
void
setScaleX(float scaleX)
void
setScaleY(float scaleY)
void
setScreenReaderFocusable(boolean screenReaderFocusable)
void
setScrollBarDefaultDelayBeforeFade(
    int scrollBarDefaultDelayBeforeFade
)
void
setScrollBarFadeDuration(int scrollBarFadeDuration)
void
setScrollBarSize(int scrollBarSize)
void
setScrollBarStyle(int style)
final void
void
void
setScrollContainer(boolean isScrollContainer)
void
setScrollIndicators(int indicators)
void
setScrollX(int value)
void
setScrollY(int value)
void
setScrollbarFadingEnabled(boolean fadeScrollbars)
void
setSelected(boolean selected)
void
setSoundEffectsEnabled(boolean soundEffectsEnabled)
void
void
void
void
setSystemUiVisibility(int visibility)

This method is deprecated.

void
void
setTextAlignment(int textAlignment)
void
setTextDirection(int textDirection)
void
final void
setTop(int top)
void
void
setTransitionAlpha(float alpha)
final void
setTransitionName(String transitionName)
void
setTransitionVisibility(int visibility)
void
setTranslationX(float translationX)
void
setTranslationY(float translationY)
void
setTranslationZ(float translationZ)
void
setVerticalFadingEdgeEnabled(boolean verticalFadingEdgeEnabled)
void
setVerticalScrollBarEnabled(boolean verticalScrollBarEnabled)
void
void
void
void
void
setVisibility(int visibility)
void
setWillNotCacheDrawing(boolean willNotCacheDrawing)

This method is deprecated.

void
setWillNotDraw(boolean willNotDraw)
void
setX(float x)
void
setY(float y)
void
setZ(float z)
boolean
ActionMode
void
final boolean
startDrag(
    ClipData data,
    View.DragShadowBuilder shadowBuilder,
    Object myLocalState,
    int flags
)

This method is deprecated.

final boolean
startDragAndDrop(
    ClipData data,
    View.DragShadowBuilder shadowBuilder,
    Object myLocalState,
    int flags
)
String
void
void
void
final void
boolean
boolean

This method is deprecated.

boolean
From android.view.ViewGroup
void
void
addExtraDataToAccessibilityNodeInfo(
    AccessibilityNodeInfo info,
    String extraDataKey,
    Bundle arguments
)
void
boolean
void
void
addView(View child)
boolean
addViewInLayout(View child, int index, ViewGroup.LayoutParams params)
void
attachLayoutAnimationParameters(
    View child,
    ViewGroup.LayoutParams params,
    int index,
    int count
)
void
attachViewToParent(View child, int index, ViewGroup.LayoutParams params)
void
boolean
void
void
childHasTransientStateChanged(
    View child,
    boolean childHasTransientState
)
void
void
void
void
void
debug(int depth)
void
void
void
detachViewsFromParent(int start, int count)
WindowInsets
boolean
void
void
dispatchCreateViewTranslationRequest(
    Map<AutofillId, long[]> viewIds,
    int[] supportedFormats,
    TranslationCapability capability,
    List<ViewTranslationRequest> requests
)
void
boolean
void
void
dispatchDrawableHotspotChanged(float x, float y)
void
void
boolean
boolean
boolean
boolean
boolean
void
dispatchPointerCaptureChanged(boolean hasCapture)
void
void
void
dispatchScrollCaptureSearch(
    Rect localVisibleRect,
    Point windowOffset,
    Consumer<ScrollCaptureTarget> targets
)
void
dispatchSetActivated(boolean activated)
void
dispatchSetPressed(boolean pressed)
void
dispatchSetSelected(boolean selected)
void
void

This method is deprecated.

void
boolean
boolean
boolean
dispatchUnhandledMove(View focused, int direction)
void
dispatchVisibilityChanged(View changedView, int visibility)
void
dispatchWindowFocusChanged(boolean hasFocus)
void
void
WindowInsets
WindowInsetsAnimation.Bounds
void

This method is deprecated.

void
void
void
View
OnBackInvokedDispatcher
void
findViewsWithText(
    ArrayList<View> outViews,
    CharSequence text,
    int flags
)
void
boolean
View
getChildAt(int index)
int
static int
getChildMeasureSpec(int spec, int padding, int childDimension)
boolean
boolean
getChildVisibleRect(View child, Rect r, Point offset)
boolean
int
View
LayoutAnimationController
Animation.AnimationListener
int
LayoutTransition
int
ViewGroupOverlay
int

This method is deprecated.

boolean
boolean
boolean
int
final void
invalidateChild(View child, Rect dirty)

This method is deprecated.

ViewParent
invalidateChildInParent(int[] location, Rect dirty)

This method is deprecated.

boolean

This method is deprecated.

boolean

This method is deprecated.

boolean
boolean

This method is deprecated.

boolean
boolean
void
final void
layout(int l, int t, int r, int b)
void
measureChild(
    View child,
    int parentWidthMeasureSpec,
    int parentHeightMeasureSpec
)
void
measureChildWithMargins(
    View child,
    int parentWidthMeasureSpec,
    int widthUsed,
    int parentHeightMeasureSpec,
    int heightUsed
)
void
measureChildren(int widthMeasureSpec, int heightMeasureSpec)
void
notifySubtreeAccessibilityStateChanged(
    View child,
    View source,
    int changeType
)
final void
final void
int[]
onCreateDrawableState(int extraSpace)
void
boolean
boolean
onNestedFling(
    View target,
    float velocityX,
    float velocityY,
    boolean consumed
)
boolean
onNestedPreFling(View target, float velocityX, float velocityY)
boolean
onNestedPrePerformAccessibilityAction(
    View target,
    int action,
    Bundle args
)
void
onNestedPreScroll(View target, int dx, int dy, int[] consumed)
void
onNestedScroll(
    View target,
    int dxConsumed,
    int dyConsumed,
    int dxUnconsumed,
    int dyUnconsumed
)
void
onNestedScrollAccepted(View child, View target, int axes)
boolean
PointerIcon
onResolvePointerIcon(MotionEvent event, int pointerIndex)
boolean
onStartNestedScroll(View child, View target, int nestedScrollAxes)
void
void
void
void
void
void
void
void
removeViewAt(int index)
void
void
removeViews(int start, int count)
void
removeViewsInLayout(int start, int count)
boolean
requestFocus(int direction, Rect previouslyFocusedRect)
boolean
void
boolean
void
void
setAddStatesFromChildren(boolean addsStates)
void

This method is deprecated.

void
setAnimationCacheEnabled(boolean enabled)

This method is deprecated.

void

This method is deprecated.

void
void

This method is deprecated.

void
setClipChildren(boolean clipChildren)
void
setDescendantFocusability(int focusability)
void
void
void
setLayoutMode(int layoutMode)
void
void
void
setPersistentDrawingCache(int drawingCacheToKeep)

This method is deprecated.

void
void
setTouchscreenBlocksFocus(boolean touchscreenBlocksFocus)
void
setTransitionGroup(boolean isTransitionGroup)
void
boolean
boolean
ActionMode
startActionModeForChild(
    View originalView,
    ActionMode.Callback callback
)
void
void
void

Constants

HORIZONTAL

Added in 1.0.0
public static final int HORIZONTAL = 0

INVALID_TYPE

Added in 1.0.0
public static final int INVALID_TYPE = -1

NO_ID

Added in 1.0.0
public static final long NO_ID = -1

NO_POSITION

Added in 1.0.0
public static final int NO_POSITION = -1

SCROLL_STATE_DRAGGING

Added in 1.0.0
public static final int SCROLL_STATE_DRAGGING = 1

The RecyclerView is currently being dragged by outside input such as user touch input.

See also
getScrollState

SCROLL_STATE_IDLE

Added in 1.0.0
public static final int SCROLL_STATE_IDLE = 0

The RecyclerView is not currently scrolling.

See also
getScrollState

SCROLL_STATE_SETTLING

Added in 1.0.0
public static final int SCROLL_STATE_SETTLING = 2

The RecyclerView is currently animating to a final position while not under outside control.

See also
getScrollState

TOUCH_SLOP_DEFAULT

Added in 1.0.0
public static final int TOUCH_SLOP_DEFAULT = 0

Constant for use with setScrollingTouchSlop. Indicates that the RecyclerView should use the standard touch slop for smooth, continuous scrolling.

TOUCH_SLOP_PAGING

Added in 1.0.0
public static final int TOUCH_SLOP_PAGING = 1

Constant for use with setScrollingTouchSlop. Indicates that the RecyclerView should use the standard touch slop for scrolling widgets that snap to a page or other coarse-grained barrier.

UNDEFINED_DURATION

Added in 1.1.0
public static final int UNDEFINED_DURATION = -2147483648

Constant that represents that a duration has not been defined.

VERTICAL

Added in 1.0.0
public static final int VERTICAL = 1

Public constructors

RecyclerView

Added in 1.0.0
public RecyclerView(@NonNull Context context)

RecyclerView

Added in 1.0.0
public RecyclerView(@NonNull Context context, @Nullable AttributeSet attrs)

RecyclerView

Added in 1.0.0
public RecyclerView(
    @NonNull Context context,
    @Nullable AttributeSet attrs,
    int defStyleAttr
)

Public methods

addFocusables

public void addFocusables(ArrayList<View> views, int direction, int focusableMode)

addItemDecoration

Added in 1.0.0
public void addItemDecoration(@NonNull RecyclerView.ItemDecoration decor)

Add an ItemDecoration to this RecyclerView. Item decorations can affect both measurement and drawing of individual item views.

Item decorations are ordered. Decorations placed earlier in the list will be run/queried/drawn first for their effects on item views. Padding added to views will be nested; a padding added by an earlier decoration will mean further item decorations in the list will be asked to draw/pad within the previous decoration's given area.

Parameters
@NonNull RecyclerView.ItemDecoration decor

Decoration to add

addItemDecoration

Added in 1.0.0
public void addItemDecoration(@NonNull RecyclerView.ItemDecoration decor, int index)

Add an ItemDecoration to this RecyclerView. Item decorations can affect both measurement and drawing of individual item views.

Item decorations are ordered. Decorations placed earlier in the list will be run/queried/drawn first for their effects on item views. Padding added to views will be nested; a padding added by an earlier decoration will mean further item decorations in the list will be asked to draw/pad within the previous decoration's given area.

Parameters
@NonNull RecyclerView.ItemDecoration decor

Decoration to add

int index

Position in the decoration chain to insert this decoration at. If this value is negative the decoration will be added at the end.

addOnChildAttachStateChangeListener

Added in 1.0.0
public void addOnChildAttachStateChangeListener(
    @NonNull RecyclerView.OnChildAttachStateChangeListener listener
)

Register a listener that will be notified whenever a child view is attached to or detached from RecyclerView.

This listener will be called when a LayoutManager or the RecyclerView decides that a child view is no longer needed. If an application associates expensive or heavyweight data with item views, this may be a good place to release or free those resources.

Parameters
@NonNull RecyclerView.OnChildAttachStateChangeListener listener

Listener to register

addOnItemTouchListener

Added in 1.0.0
public void addOnItemTouchListener(
    @NonNull RecyclerView.OnItemTouchListener listener
)

Add an OnItemTouchListener to intercept touch events before they are dispatched to child views or this view's standard scrolling behavior.

Client code may use listeners to implement item manipulation behavior. Once a listener returns true from onInterceptTouchEvent its onTouchEvent method will be called for each incoming MotionEvent until the end of the gesture.

Parameters
@NonNull RecyclerView.OnItemTouchListener listener

Listener to add

addOnScrollListener

Added in 1.0.0
public void addOnScrollListener(@NonNull RecyclerView.OnScrollListener listener)

Add a listener that will be notified of any changes in scroll state or position.

Components that add a listener should take care to remove it when finished. Other components that take ownership of a view may call clearOnScrollListeners to remove all attached listeners.

Parameters
@NonNull RecyclerView.OnScrollListener listener

listener to set

addRecyclerListener

Added in 1.2.0
public void addRecyclerListener(@NonNull RecyclerView.RecyclerListener listener)

Register a listener that will be notified whenever a child view is recycled.

The listeners will be called when a LayoutManager or the RecyclerView decides that a child view is no longer needed. If an application associates data with the item views being recycled, this may be a good place to release or free those resources.

Parameters
@NonNull RecyclerView.RecyclerListener listener

Listener to register.

clearOnChildAttachStateChangeListeners

Added in 1.0.0
public void clearOnChildAttachStateChangeListeners()

Removes all listeners that were added via addOnChildAttachStateChangeListener.

clearOnScrollListeners

Added in 1.0.0
public void clearOnScrollListeners()

Remove all secondary listener that were notified of any changes in scroll state or position.

computeHorizontalScrollExtent

Added in 1.0.0
public int computeHorizontalScrollExtent()

Compute the horizontal extent of the horizontal scrollbar's thumb within the horizontal range. This value is used to compute the length of the thumb within the scrollbar's track.

The range is expressed in arbitrary units that must be the same as the units used by computeHorizontalScrollRange and computeHorizontalScrollOffset.

Default implementation returns 0.

If you want to support scroll bars, override computeHorizontalScrollExtent in your LayoutManager.

Returns
int

The horizontal extent of the scrollbar's thumb

computeHorizontalScrollOffset

Added in 1.0.0
public int computeHorizontalScrollOffset()

Compute the horizontal offset of the horizontal scrollbar's thumb within the horizontal range. This value is used to compute the position of the thumb within the scrollbar's track.

The range is expressed in arbitrary units that must be the same as the units used by computeHorizontalScrollRange and computeHorizontalScrollExtent.

Default implementation returns 0.

If you want to support scroll bars, override computeHorizontalScrollOffset in your LayoutManager.

Returns
int

The horizontal offset of the scrollbar's thumb

See also
computeHorizontalScrollOffset

(RecyclerView.State)

computeHorizontalScrollRange

Added in 1.0.0
public int computeHorizontalScrollRange()

Compute the horizontal range that the horizontal scrollbar represents.

The range is expressed in arbitrary units that must be the same as the units used by computeHorizontalScrollExtent and computeHorizontalScrollOffset.

Default implementation returns 0.

If you want to support scroll bars, override computeHorizontalScrollRange in your LayoutManager.

Returns
int

The total horizontal range represented by the horizontal scrollbar

computeVerticalScrollExtent

Added in 1.0.0
public int computeVerticalScrollExtent()

Compute the vertical extent of the vertical scrollbar's thumb within the vertical range. This value is used to compute the length of the thumb within the scrollbar's track.

The range is expressed in arbitrary units that must be the same as the units used by computeVerticalScrollRange and computeVerticalScrollOffset.

Default implementation returns 0.

If you want to support scroll bars, override computeVerticalScrollExtent in your LayoutManager.

Returns
int

The vertical extent of the scrollbar's thumb

computeVerticalScrollOffset

Added in 1.0.0
public int computeVerticalScrollOffset()

Compute the vertical offset of the vertical scrollbar's thumb within the vertical range. This value is used to compute the position of the thumb within the scrollbar's track.

The range is expressed in arbitrary units that must be the same as the units used by computeVerticalScrollRange and computeVerticalScrollExtent.

Default implementation returns 0.

If you want to support scroll bars, override computeVerticalScrollOffset in your LayoutManager.

Returns
int

The vertical offset of the scrollbar's thumb

See also
computeVerticalScrollOffset

(RecyclerView.State)

computeVerticalScrollRange

Added in 1.0.0
public int computeVerticalScrollRange()

Compute the vertical range that the vertical scrollbar represents.

The range is expressed in arbitrary units that must be the same as the units used by computeVerticalScrollExtent and computeVerticalScrollOffset.

Default implementation returns 0.

If you want to support scroll bars, override computeVerticalScrollRange in your LayoutManager.

Returns
int

The total vertical range represented by the vertical scrollbar

dispatchKeyEvent

public boolean dispatchKeyEvent(@Nullable KeyEvent event)

dispatchNestedFling

public boolean dispatchNestedFling(float velocityX, float velocityY, boolean consumed)

dispatchNestedPreFling

public boolean dispatchNestedPreFling(float velocityX, float velocityY)

dispatchNestedPreScroll

public boolean dispatchNestedPreScroll(
    int dx,
    int dy,
    int[] consumed,
    int[] offsetInWindow
)

dispatchNestedPreScroll

Added in 1.0.0
public boolean dispatchNestedPreScroll(
    int dx,
    int dy,
    int[] consumed,
    int[] offsetInWindow,
    int type
)

Dispatch one step of a nested scroll in progress before this view consumes any portion of it.

Nested pre-scroll events are to nested scroll events what touch intercept is to touch. dispatchNestedPreScroll offers an opportunity for the parent view in a nested scrolling operation to consume some or all of the scroll operation before the child view consumes it.

Parameters
int dx

Horizontal scroll distance in pixels

int dy

Vertical scroll distance in pixels

int[] consumed

Output. If not null, consumed[0] will contain the consumed component of dx and consumed[1] the consumed dy.

int[] offsetInWindow

Optional. If not null, on return this will contain the offset in local view coordinates of this view from before this operation to after it completes. View implementations may use this to adjust expected input coordinate tracking.

int type

the type of input which cause this scroll event

Returns
boolean

true if the parent consumed some or all of the scroll delta

dispatchNestedScroll

public boolean dispatchNestedScroll(
    int dxConsumed,
    int dyConsumed,
    int dxUnconsumed,
    int dyUnconsumed,
    int[] offsetInWindow
)

dispatchNestedScroll

Added in 1.0.0
public boolean dispatchNestedScroll(
    int dxConsumed,
    int dyConsumed,
    int dxUnconsumed,
    int dyUnconsumed,
    int[] offsetInWindow,
    int type
)

Dispatch one step of a nested scroll in progress.

Implementations of views that support nested scrolling should call this to report info about a scroll in progress to the current nested scrolling parent. If a nested scroll is not currently in progress or nested scrolling is not enabled for this view this method does nothing.

Compatible View implementations should also call dispatchNestedPreScroll before consuming a component of the scroll event themselves.

Parameters
int dxConsumed

Horizontal distance in pixels consumed by this view during this scroll step

int dyConsumed

Vertical distance in pixels consumed by this view during this scroll step

int dxUnconsumed

Horizontal scroll distance in pixels not consumed by this view

int dyUnconsumed

Horizontal scroll distance in pixels not consumed by this view

int[] offsetInWindow

Optional. If not null, on return this will contain the offset in local view coordinates of this view from before this operation to after it completes. View implementations may use this to adjust expected input coordinate tracking.

int type

the type of input which cause this scroll event

Returns
boolean

true if the event was dispatched, false if it could not be dispatched.

dispatchNestedScroll

Added in 1.1.0
public final void dispatchNestedScroll(
    int dxConsumed,
    int dyConsumed,
    int dxUnconsumed,
    int dyUnconsumed,
    int[] offsetInWindow,
    int type,
    @NonNull int[] consumed
)

Dispatch one step of a nested scroll in progress.

Implementations of views that support nested scrolling should call this to report info about a scroll in progress to the current nested scrolling parent. If a nested scroll is not currently in progress or nested scrolling is not enabled for this view this method does nothing.

Compatible View implementations should also call dispatchNestedPreScroll before consuming a component of the scroll event themselves.

The original nested scrolling child (where the input events were received to start the scroll) must provide a non-null consumed parameter with values {0, 0}.

Parameters
int dxConsumed

Horizontal distance in pixels consumed by this view during this scroll step

int dyConsumed

Vertical distance in pixels consumed by this view during this scroll step

int dxUnconsumed

Horizontal scroll distance in pixels not consumed by this view

int dyUnconsumed

Horizontal scroll distance in pixels not consumed by this view

int[] offsetInWindow

Optional. If not null, on return this will contain the offset in local view coordinates of this view from before this operation to after it completes. View implementations may use this to adjust expected input coordinate tracking.

int type

the type of input which cause this scroll event

@NonNull int[] consumed

Output. Upon this method returning, will contain the original values plus any scroll distances consumed by all of this view's nested scrolling parents up the view hierarchy. Index 0 for the x dimension, and index 1 for the y dimension

See also
onNestedScroll

dispatchPopulateAccessibilityEvent

public boolean dispatchPopulateAccessibilityEvent(AccessibilityEvent event)

draw

public void draw(@NonNull Canvas c)

drawChild

Added in 1.0.0
public boolean drawChild(@NonNull Canvas canvas, View child, long drawingTime)

findChildViewUnder

Added in 1.0.0
public @Nullable View findChildViewUnder(float x, float y)

Find the topmost view under the given point.

Parameters
float x

Horizontal position in pixels to search

float y

Vertical position in pixels to search

Returns
@Nullable View

The child view under (x, y) or null if no matching child is found

findContainingItemView

Added in 1.0.0
public @Nullable View findContainingItemView(@NonNull View view)

Traverses the ancestors of the given view and returns the item view that contains it and also a direct child of the RecyclerView. This returned view can be used to get the ViewHolder by calling getChildViewHolder.

Parameters
@NonNull View view

The view that is a descendant of the RecyclerView.

Returns
@Nullable View

The direct child of the RecyclerView which contains the given view or null if the provided view is not a descendant of this RecyclerView.

findContainingViewHolder

Added in 1.0.0
public @Nullable RecyclerView.ViewHolder findContainingViewHolder(@NonNull View view)

Returns the ViewHolder that contains the given view.

Parameters
@NonNull View view

The view that is a descendant of the RecyclerView.

Returns
@Nullable RecyclerView.ViewHolder

The ViewHolder that contains the given view or null if the provided view is not a descendant of this RecyclerView.

findViewHolderForAdapterPosition

Added in 1.0.0
public @Nullable RecyclerView.ViewHolder findViewHolderForAdapterPosition(int position)

Return the ViewHolder for the item in the given position of the data set. Unlike findViewHolderForLayoutPosition this method takes into account any pending adapter changes that may not be reflected to the layout yet. On the other hand, if notifyDataSetChanged has been called but the new layout has not been calculated yet, this method will return null since the new positions of views are unknown until the layout is calculated.

This method checks only the children of RecyclerView. If the item at the given position is not laid out, it will not create a new one.

When the ItemAnimator is running a change animation, there might be 2 ViewHolders representing the same Item. In this case, the updated ViewHolder will be returned.

Parameters
int position

The position of the item in the data set of the adapter

Returns
@Nullable RecyclerView.ViewHolder

The ViewHolder at position or null if there is no such item

findViewHolderForItemId

Added in 1.0.0
public RecyclerView.ViewHolder findViewHolderForItemId(long id)

Return the ViewHolder for the item with the given id. The RecyclerView must use an Adapter with stableIds to return a non-null value.

This method checks only the children of RecyclerView. If the item with the given id is not laid out, it will not create a new one. When the ItemAnimator is running a change animation, there might be 2 ViewHolders with the same id. In this case, the updated ViewHolder will be returned.

Parameters
long id

The id for the requested item

Returns
RecyclerView.ViewHolder

The ViewHolder with the given id or null if there is no such item

findViewHolderForLayoutPosition

Added in 1.0.0
public @Nullable RecyclerView.ViewHolder findViewHolderForLayoutPosition(int position)

Return the ViewHolder for the item in the given position of the data set as of the latest layout pass.

This method checks only the children of RecyclerView. If the item at the given position is not laid out, it will not create a new one.

Note that when Adapter contents change, ViewHolder positions are not updated until the next layout calculation. If there are pending adapter updates, the return value of this method may not match your adapter contents. You can use #getBindingAdapterPosition to get the current adapter position of a ViewHolder. If the Adapter that is assigned to the RecyclerView is an adapter that combines other adapters (e.g. ConcatAdapter), you can use the getBindingAdapter) to find the position relative to the Adapter that bound the ViewHolder.

When the ItemAnimator is running a change animation, there might be 2 ViewHolders with the same layout position representing the same Item. In this case, the updated ViewHolder will be returned.

Parameters
int position

The position of the item in the data set of the adapter

Returns
@Nullable RecyclerView.ViewHolder

The ViewHolder at position or null if there is no such item

findViewHolderForPosition

Added in 1.0.0
Deprecated in 1.0.0
public @Nullable RecyclerView.ViewHolder findViewHolderForPosition(int position)

fling

Added in 1.0.0
public boolean fling(int velocityX, int velocityY)

Begin a standard fling with an initial velocity along each axis in pixels per second. If the velocity given is below the system-defined minimum this method will return false and no fling will occur.

Parameters
int velocityX

Initial horizontal velocity in pixels per second

int velocityY

Initial vertical velocity in pixels per second

Returns
boolean

true if the fling was started, false if the velocity was too low to fling or LayoutManager does not support scrolling in the axis fling is issued.

focusSearch

public View focusSearch(View focused, int direction)

Since RecyclerView is a collection ViewGroup that includes virtual children (items that are in the Adapter but not visible in the UI), it employs a more involved focus search strategy that differs from other ViewGroups.

It first does a focus search within the RecyclerView. If this search finds a View that is in the focus direction with respect to the currently focused View, RecyclerView returns that child as the next focus target. When it cannot find such child, it calls onFocusSearchFailed to layout more Views in the focus search direction. If LayoutManager adds a View that matches the focus search criteria, it will be returned as the focus search result. Otherwise, RecyclerView will call parent to handle the focus search like a regular ViewGroup.

When the direction is FOCUS_FORWARD or FOCUS_BACKWARD, a View that is not in the focus direction is still valid focus target which may not be the desired behavior if the Adapter has more children in the focus direction. To handle this case, RecyclerView converts the focus direction to an absolute direction and makes a preliminary focus search in that direction. If there are no Views to gain focus, it will call onFocusSearchFailed before running a focus search with the original (relative) direction. This allows RecyclerView to provide better candidates to the focus search while still allowing the view system to take focus from the RecyclerView and give it to a more suitable child if such child exists.

Parameters
View focused

The view that currently has focus

int direction

One of FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT, FOCUS_FORWARD, FOCUS_BACKWARD or 0 for not applicable.

Returns
View

A new View that can be the next focus after the focused View

generateLayoutParams

public ViewGroup.LayoutParams generateLayoutParams(AttributeSet attrs)

getAccessibilityClassName

public CharSequence getAccessibilityClassName()

getAdapter

Added in 1.0.0
public @Nullable RecyclerView.Adapter getAdapter()

Retrieves the previously set adapter or null if no adapter is set.

Returns
@Nullable RecyclerView.Adapter

The previously set adapter

See also
setAdapter

getBaseline

public int getBaseline()

Return the offset of the RecyclerView's text baseline from the its top boundary. If the LayoutManager of this RecyclerView does not support baseline alignment, this method returns -1.

Returns
int

the offset of the baseline within the RecyclerView's bounds or -1 if baseline alignment is not supported

getChildAdapterPosition

Added in 1.0.0
public int getChildAdapterPosition(@NonNull View child)

Return the adapter position that the given child view corresponds to.

Parameters
@NonNull View child

Child View to query

Returns
int

Adapter position corresponding to the given view or NO_POSITION

getChildItemId

Added in 1.0.0
public long getChildItemId(@NonNull View child)

Return the stable item id that the given child view corresponds to.

Parameters
@NonNull View child

Child View to query

Returns
long

Item id corresponding to the given view or NO_ID

getChildLayoutPosition

Added in 1.0.0
public int getChildLayoutPosition(@NonNull View child)

Return the adapter position of the given child view as of the latest completed layout pass.

This position may not be equal to Item's adapter position if there are pending changes in the adapter which have not been reflected to the layout yet.

Parameters
@NonNull View child

Child View to query

Returns
int

Adapter position of the given View as of last layout pass or NO_POSITION if the View is representing a removed item.

getChildPosition

Added in 1.0.0
Deprecated in 1.0.0
public int getChildPosition(@NonNull View child)

getChildViewHolder

Added in 1.0.0
public RecyclerView.ViewHolder getChildViewHolder(@NonNull View child)

Retrieve the ViewHolder for the given child view.

Parameters
@NonNull View child

Child of this RecyclerView to query for its ViewHolder

Returns
RecyclerView.ViewHolder

The child view's ViewHolder

getClipToPadding

public boolean getClipToPadding()

Returns whether this RecyclerView will clip its children to its padding, and resize (but not clip) any EdgeEffect to the padded region, if padding is present.

By default, children are clipped to the padding of their parent RecyclerView. This clipping behavior is only enabled if padding is non-zero.

name android:clipToPadding

Returns
boolean

true if this RecyclerView clips children to its padding and resizes (but doesn't clip) any EdgeEffect to the padded region, false otherwise.

getCompatAccessibilityDelegate

Added in 1.0.0
public @Nullable RecyclerViewAccessibilityDelegate getCompatAccessibilityDelegate()

Returns the accessibility delegate compatibility implementation used by the RecyclerView.

Returns
@Nullable RecyclerViewAccessibilityDelegate

An instance of AccessibilityDelegateCompat used by RecyclerView

getDecoratedBoundsWithMargins

Added in 1.0.0
public void getDecoratedBoundsWithMargins(@NonNull View view, @NonNull Rect outBounds)

Returns the bounds of the view including its decoration and margins.

Parameters
@NonNull View view

The view element to check

@NonNull Rect outBounds

A rect that will receive the bounds of the element including its decoration and margins.

getEdgeEffectFactory

Added in 1.0.0
public @NonNull RecyclerView.EdgeEffectFactory getEdgeEffectFactory()

Retrieves the previously set EdgeEffectFactory or the default factory if nothing was set.

getItemAnimator

Added in 1.0.0
public @Nullable RecyclerView.ItemAnimator getItemAnimator()

Gets the current ItemAnimator for this RecyclerView. A null return value indicates that there is no animator and that item changes will happen without any animations. By default, RecyclerView instantiates and uses an instance of DefaultItemAnimator.

Returns
@Nullable RecyclerView.ItemAnimator

ItemAnimator The current ItemAnimator. If null, no animations will occur when changes occur to the items in this RecyclerView.

getItemDecorationAt

Added in 1.0.0
public @NonNull RecyclerView.ItemDecoration getItemDecorationAt(int index)

Returns an ItemDecoration previously added to this RecyclerView.

Parameters
int index

The index position of the desired ItemDecoration.

Returns
@NonNull RecyclerView.ItemDecoration

the ItemDecoration at index position

Throws
java.lang.IndexOutOfBoundsException

on invalid index

getItemDecorationCount

Added in 1.0.0
public int getItemDecorationCount()

Returns the number of ItemDecoration currently added to this RecyclerView.

Returns
int

number of ItemDecorations currently added added to this RecyclerView.

getLayoutManager

Added in 1.0.0
public @Nullable RecyclerView.LayoutManager getLayoutManager()

Return the LayoutManager currently responsible for layout policy for this RecyclerView.

Returns
@Nullable RecyclerView.LayoutManager

The currently bound LayoutManager

getMaxFlingVelocity

Added in 1.0.0
public int getMaxFlingVelocity()

Returns the maximum fling velocity used by this RecyclerView.

Returns
int

The maximum fling velocity used by this RecyclerView.

getMinFlingVelocity

Added in 1.0.0
public int getMinFlingVelocity()

Returns the minimum velocity to start a fling.

Returns
int

The minimum velocity to start a fling

getOnFlingListener

Added in 1.0.0
public @Nullable RecyclerView.OnFlingListener getOnFlingListener()

Get the current OnFlingListener from this RecyclerView.

Returns
@Nullable RecyclerView.OnFlingListener

The OnFlingListener instance currently set (can be null).

getPreserveFocusAfterLayout

Added in 1.0.0
public boolean getPreserveFocusAfterLayout()

Returns true if the RecyclerView should attempt to preserve currently focused Adapter Item's focus even if the View representing the Item is replaced during a layout calculation.

By default, this value is true.

Returns
boolean

True if the RecyclerView will try to preserve focused Item after a layout if it loses focus.

getRecycledViewPool

Added in 1.0.0
public @NonNull RecyclerView.RecycledViewPool getRecycledViewPool()

Retrieve this RecyclerView's RecycledViewPool. This method will never return null; if no pool is set for this view a new one will be created. See setRecycledViewPool for more information.

Returns
@NonNull RecyclerView.RecycledViewPool

The pool used to store recycled item views for reuse.

getScrollState

Added in 1.0.0
public int getScrollState()

Return the current scrolling state of the RecyclerView.

hasFixedSize

Added in 1.0.0
public boolean hasFixedSize()
Returns
boolean

true if the app has specified that changes in adapter content cannot change the size of the RecyclerView itself.

hasNestedScrollingParent

public boolean hasNestedScrollingParent()

hasNestedScrollingParent

Added in 1.0.0
public boolean hasNestedScrollingParent(int type)

Returns true if this view has a nested scrolling parent for the given input type.

The presence of a nested scrolling parent indicates that this view has initiated a nested scroll and it was accepted by an ancestor view further up the view hierarchy.

Parameters
int type

the type of input which cause this scroll event

Returns
boolean

whether this view has a nested scrolling parent

hasPendingAdapterUpdates

Added in 1.0.0
public boolean hasPendingAdapterUpdates()

Returns whether there are pending adapter updates which are not yet applied to the layout.

If this method returns true, it means that what user is currently seeing may not reflect them adapter contents (depending on what has changed). You may use this information to defer or cancel some operations.

This method returns true if RecyclerView has not yet calculated the first layout after it is attached to the Window or the Adapter has been replaced.

Returns
boolean

True if there are some adapter updates which are not yet reflected to layout or false if layout is up to date.

invalidateItemDecorations

Added in 1.0.0
public void invalidateItemDecorations()

Invalidates all ItemDecorations. If RecyclerView has item decorations, calling this method will trigger a requestLayout call.

isAnimating

Added in 1.0.0
public boolean isAnimating()

Returns true if RecyclerView is currently running some animations.

If you want to be notified when animations are finished, use isRunning.

Returns
boolean

True if there are some item animations currently running or waiting to be started.

isAttachedToWindow

public boolean isAttachedToWindow()

Returns true if RecyclerView is attached to window.

isComputingLayout

Added in 1.0.0
public boolean isComputingLayout()

Returns whether RecyclerView is currently computing a layout.

If this method returns true, it means that RecyclerView is in a lockdown state and any attempt to update adapter contents will result in an exception because adapter contents cannot be changed while RecyclerView is trying to compute the layout.

It is very unlikely that your code will be running during this state as it is called by the framework when a layout traversal happens or RecyclerView starts to scroll in response to system events (touch, accessibility etc).

This case may happen if you have some custom logic to change adapter contents in response to a View callback (e.g. focus change callback) which might be triggered during a layout calculation. In these cases, you should just postpone the change using a Handler or a similar mechanism.

Returns
boolean

true if RecyclerView is currently computing a layout, false otherwise

isLayoutFrozen

Added in 1.0.0
Deprecated in 1.1.0
public boolean isLayoutFrozen()
Returns
boolean

true if layout and scroll are frozen

isLayoutSuppressed

Added in 1.1.0
public final boolean isLayoutSuppressed()

Returns whether layout and scroll calls on this container are currently being suppressed, due to an earlier call to suppressLayout.

Returns
boolean

true if layout and scroll are currently suppressed, false otherwise.

isNestedScrollingEnabled

public boolean isNestedScrollingEnabled()

nestedScrollBy

Added in 1.2.0
public void nestedScrollBy(int x, int y)

Same as scrollBy, but also participates in nested scrolling.

Parameters
int x

The amount of horizontal scroll requested

int y

The amount of vertical scroll requested

offsetChildrenHorizontal

Added in 1.0.0
public void offsetChildrenHorizontal(@Px int dx)

Offset the bounds of all child views by dx pixels. Useful for implementing simple scrolling in LayoutManagers.

Parameters
@Px int dx

Horizontal pixel offset to apply to the bounds of all child views

offsetChildrenVertical

Added in 1.0.0
public void offsetChildrenVertical(@Px int dy)

Offset the bounds of all child views by dy pixels. Useful for implementing simple scrolling in LayoutManagers.

Parameters
@Px int dy

Vertical pixel offset to apply to the bounds of all child views

onChildAttachedToWindow

Added in 1.0.0
public void onChildAttachedToWindow(@NonNull View child)

Called when an item view is attached to this RecyclerView.

Subclasses of RecyclerView may want to perform extra bookkeeping or modifications of child views as they become attached. This will be called before a LayoutManager measures or lays out the view and is a good time to perform these changes.

Parameters
@NonNull View child

Child view that is now attached to this RecyclerView and its associated window

onChildDetachedFromWindow

Added in 1.0.0
public void onChildDetachedFromWindow(@NonNull View child)

Called when an item view is detached from this RecyclerView.

Subclasses of RecyclerView may want to perform extra bookkeeping or modifications of child views as they become detached. This will be called as a LayoutManager fully detaches the child view from the parent and its window.

Parameters
@NonNull View child

Child view that is now detached from this RecyclerView and its associated window

onDraw

Added in 1.0.0
public void onDraw(@NonNull Canvas c)

onGenericMotionEvent

public boolean onGenericMotionEvent(MotionEvent event)

onInterceptTouchEvent

public boolean onInterceptTouchEvent(MotionEvent e)

onScrollStateChanged

Added in 1.0.0
public void onScrollStateChanged(int state)

Called when the scroll state of this RecyclerView changes. Subclasses should use this method to respond to state changes instead of an explicit listener.

This method will always be invoked before listeners, but after the LayoutManager responds to the scroll state change.

Parameters
int state

the new scroll state, one of SCROLL_STATE_IDLE, SCROLL_STATE_DRAGGING or SCROLL_STATE_SETTLING

onScrolled

Added in 1.0.0
public void onScrolled(@Px int dx, @Px int dy)

Called when the scroll position of this RecyclerView changes. Subclasses should use this method to respond to scrolling within the adapter's data set instead of an explicit listener.

This method will always be invoked before listeners. If a subclass needs to perform any additional upkeep or bookkeeping after scrolling but before listeners run, this is a good place to do so.

This differs from onScrollChanged in that it receives the distance scrolled in either direction within the adapter's data set instead of absolute scroll coordinates. Since RecyclerView cannot compute the absolute scroll position from any arbitrary point in the data set, onScrollChanged will always receive the current getScrollX and getScrollY values which do not correspond to the data set scroll position. However, some subclasses may choose to use these fields as special offsets.

Parameters
@Px int dx

horizontal distance scrolled in pixels

@Px int dy

vertical distance scrolled in pixels

onTouchEvent

public boolean onTouchEvent(MotionEvent e)

removeItemDecoration

Added in 1.0.0
public void removeItemDecoration(@NonNull RecyclerView.ItemDecoration decor)

Remove an ItemDecoration from this RecyclerView.

The given decoration will no longer impact the measurement and drawing of item views.

Parameters
@NonNull RecyclerView.ItemDecoration decor

Decoration to remove

removeItemDecorationAt

Added in 1.0.0
public void removeItemDecorationAt(int index)

Removes the ItemDecoration associated with the supplied index position.

Parameters
int index

The index position of the ItemDecoration to be removed.

removeOnChildAttachStateChangeListener

Added in 1.0.0
public void removeOnChildAttachStateChangeListener(
    @NonNull RecyclerView.OnChildAttachStateChangeListener listener
)

Removes the provided listener from child attached state listeners list.

Parameters
@NonNull RecyclerView.OnChildAttachStateChangeListener listener

Listener to unregister

removeOnItemTouchListener

Added in 1.0.0
public void removeOnItemTouchListener(
    @NonNull RecyclerView.OnItemTouchListener listener
)

Remove an OnItemTouchListener. It will no longer be able to intercept touch events.

Parameters
@NonNull RecyclerView.OnItemTouchListener listener

Listener to remove

removeOnScrollListener

Added in 1.0.0
public void removeOnScrollListener(@NonNull RecyclerView.OnScrollListener listener)

Remove a listener that was notified of any changes in scroll state or position.

Parameters
@NonNull RecyclerView.OnScrollListener listener

listener to set or null to clear

removeRecyclerListener

Added in 1.2.0
public void removeRecyclerListener(@NonNull RecyclerView.RecyclerListener listener)

Removes the provided listener from RecyclerListener list.

Parameters
@NonNull RecyclerView.RecyclerListener listener

Listener to unregister.

requestChildFocus

public void requestChildFocus(View child, View focused)

requestChildRectangleOnScreen

public boolean requestChildRectangleOnScreen(View child, Rect rect, boolean immediate)

requestDisallowInterceptTouchEvent

public void requestDisallowInterceptTouchEvent(boolean disallowIntercept)

requestLayout

public void requestLayout()

scrollBy

public void scrollBy(int x, int y)

scrollTo

public void scrollTo(int x, int y)

scrollToPosition

Added in 1.0.0
public void scrollToPosition(int position)

Convenience method to scroll to a certain position. RecyclerView does not implement scrolling logic, rather forwards the call to scrollToPosition

Parameters
int position

Scroll to this adapter position

See also
scrollToPosition

sendAccessibilityEventUnchecked

public void sendAccessibilityEventUnchecked(AccessibilityEvent event)

setAccessibilityDelegateCompat

Added in 1.0.0
public void setAccessibilityDelegateCompat(
    @Nullable RecyclerViewAccessibilityDelegate accessibilityDelegate
)

Sets the accessibility delegate compatibility implementation used by RecyclerView.

Parameters
@Nullable RecyclerViewAccessibilityDelegate accessibilityDelegate

The accessibility delegate to be used by RecyclerView.

setAdapter

Added in 1.0.0
public void setAdapter(@Nullable RecyclerView.Adapter adapter)

Set a new adapter to provide child views on demand.

When adapter is changed, all existing views are recycled back to the pool. If the pool has only one adapter, it will be cleared.

Parameters
@Nullable RecyclerView.Adapter adapter

The new adapter to set, or null to set no adapter.

See also
swapAdapter

setChildDrawingOrderCallback

Added in 1.0.0
public void setChildDrawingOrderCallback(
    @Nullable RecyclerView.ChildDrawingOrderCallback childDrawingOrderCallback
)

Sets the ChildDrawingOrderCallback to be used for drawing children.

See getChildDrawingOrder for details. Calling this method will always call setChildrenDrawingOrderEnabled. The parameter will be true if childDrawingOrderCallback is not null, false otherwise.

Note that child drawing order may be overridden by View's elevation.

Parameters
@Nullable RecyclerView.ChildDrawingOrderCallback childDrawingOrderCallback

The ChildDrawingOrderCallback to be used by the drawing system.

setClipToPadding

public void setClipToPadding(boolean clipToPadding)

setDebugAssertionsEnabled

Added in 1.4.0-alpha01
public static void setDebugAssertionsEnabled(boolean debugAssertionsEnabled)

Enable internal assertions about RecyclerView's state and throw exceptions if the assertions are violated.

This is primarily intended to diagnose problems with RecyclerView, and should not be enabled in production unless you have a specific reason to do so.

Enabling this may negatively affect performance and/or stability.

Parameters
boolean debugAssertionsEnabled

true to enable assertions; false to disable them

setEdgeEffectFactory

Added in 1.0.0
public void setEdgeEffectFactory(
    @NonNull RecyclerView.EdgeEffectFactory edgeEffectFactory
)

Set a EdgeEffectFactory for this RecyclerView.

When a new EdgeEffectFactory is set, any existing over-scroll effects are cleared and new effects are created as needed using createEdgeEffect

Parameters
@NonNull RecyclerView.EdgeEffectFactory edgeEffectFactory

The EdgeEffectFactory instance.

setHasFixedSize

Added in 1.0.0
public void setHasFixedSize(boolean hasFixedSize)

RecyclerView can perform several optimizations if it can know in advance that RecyclerView's size is not affected by the adapter contents. RecyclerView can still change its size based on other factors (e.g. its parent's size) but this size calculation cannot depend on the size of its children or contents of its adapter (except the number of items in the adapter).

If your use of RecyclerView falls into this category, set this to true. It will allow RecyclerView to avoid invalidating the whole layout when its adapter contents change.

Parameters
boolean hasFixedSize

true if adapter changes cannot affect the size of the RecyclerView.

setItemAnimator

Added in 1.0.0
public void setItemAnimator(@Nullable RecyclerView.ItemAnimator animator)

Sets the ItemAnimator that will handle animations involving changes to the items in this RecyclerView. By default, RecyclerView instantiates and uses an instance of DefaultItemAnimator. Whether item animations are enabled for the RecyclerView depends on the ItemAnimator and whether the LayoutManager supports item animations.

Parameters
@Nullable RecyclerView.ItemAnimator animator

The ItemAnimator being set. If null, no animations will occur when changes occur to the items in this RecyclerView.

setItemViewCacheSize

Added in 1.0.0
public void setItemViewCacheSize(int size)

Set the number of offscreen views to retain before adding them to the potentially shared recycled view pool.

The offscreen view cache stays aware of changes in the attached adapter, allowing a LayoutManager to reuse those views unmodified without needing to return to the adapter to rebind them.

Parameters
int size

Number of views to cache offscreen before returning them to the general recycled view pool

setLayoutFrozen

Added in 1.0.0
Deprecated in 1.1.0
public void setLayoutFrozen(boolean frozen)

Enable or disable layout and scroll. After setLayoutFrozen(true) is called, Layout requests will be postponed until setLayoutFrozen(false) is called; child views are not updated when RecyclerView is frozen, smoothScrollBy, scrollBy, scrollToPosition and smoothScrollToPosition are dropped; TouchEvents and GenericMotionEvents are dropped; onFocusSearchFailed will not be called.

setLayoutFrozen(true) does not prevent app from directly calling scrollToPosition, smoothScrollToPosition.

setAdapter and swapAdapter will automatically stop frozen.

Note: Running ItemAnimator is not stopped automatically, it's caller's responsibility to call ItemAnimator.end().

Parameters
boolean frozen

true to freeze layout and scroll, false to re-enable.

setLayoutManager

Added in 1.0.0
public void setLayoutManager(@Nullable RecyclerView.LayoutManager layout)

Set the LayoutManager that this RecyclerView will use.

In contrast to other adapter-backed views such as android.widget.ListView or android.widget.GridView, RecyclerView allows client code to provide custom layout arrangements for child views. These arrangements are controlled by the LayoutManager. A LayoutManager must be provided for RecyclerView to function.

Several default strategies are provided for common uses such as lists and grids.

Parameters
@Nullable RecyclerView.LayoutManager layout

LayoutManager to use

setLayoutTransition

Added in 1.1.0
Deprecated in 1.1.0
public void setLayoutTransition(LayoutTransition transition)

setNestedScrollingEnabled

public void setNestedScrollingEnabled(boolean enabled)

setOnFlingListener

Added in 1.0.0
public void setOnFlingListener(
    @Nullable RecyclerView.OnFlingListener onFlingListener
)

Set a OnFlingListener for this RecyclerView.

If the OnFlingListener is set then it will receive calls to fling and will be able to intercept them.

Parameters
@Nullable RecyclerView.OnFlingListener onFlingListener

The OnFlingListener instance.

setOnScrollListener

Added in 1.0.0
Deprecated in 1.0.0
public void setOnScrollListener(@Nullable RecyclerView.OnScrollListener listener)

Set a listener that will be notified of any changes in scroll state or position.

Parameters
@Nullable RecyclerView.OnScrollListener listener

Listener to set or null to clear

setPreserveFocusAfterLayout

Added in 1.0.0
public void setPreserveFocusAfterLayout(boolean preserveFocusAfterLayout)

Set whether the RecyclerView should try to keep the same Item focused after a layout calculation or not.

Usually, LayoutManagers keep focused views visible before and after layout but sometimes, views may lose focus during a layout calculation as their state changes or they are replaced with another view due to type change or animation. In these cases, RecyclerView can request focus on the new view automatically.

Parameters
boolean preserveFocusAfterLayout

Whether RecyclerView should preserve focused Item during a layout calculations. Defaults to true.

setRecycledViewPool

Added in 1.0.0
public void setRecycledViewPool(@Nullable RecyclerView.RecycledViewPool pool)

Recycled view pools allow multiple RecyclerViews to share a common pool of scrap views. This can be useful if you have multiple RecyclerViews with adapters that use the same view types, for example if you have several data sets with the same kinds of item views displayed by a androidx.viewpager.widget.ViewPager.

Parameters
@Nullable RecyclerView.RecycledViewPool pool

Pool to set. If this parameter is null a new pool will be created and used.

setRecyclerListener

Added in 1.0.0
Deprecated in 1.2.0
public void setRecyclerListener(@Nullable RecyclerView.RecyclerListener listener)

Register a listener that will be notified whenever a child view is recycled.

This listener will be called when a LayoutManager or the RecyclerView decides that a child view is no longer needed. If an application associates expensive or heavyweight data with item views, this may be a good place to release or free those resources.

Parameters
@Nullable RecyclerView.RecyclerListener listener

Listener to register, or null to clear

setScrollingTouchSlop

Added in 1.0.0
public void setScrollingTouchSlop(int slopConstant)

Configure the scrolling touch slop for a specific use case. Set up the RecyclerView's scrolling motion threshold based on common usages. Valid arguments are TOUCH_SLOP_DEFAULT and TOUCH_SLOP_PAGING.

Parameters
int slopConstant

One of the TOUCH_SLOP_ constants representing the intended usage of this RecyclerView

setVerboseLoggingEnabled

Added in 1.4.0-alpha01
public static void setVerboseLoggingEnabled(boolean verboseLoggingEnabled)

Enable verbose logging within RecyclerView itself.

Enabling this may negatively affect performance and reduce the utility of logcat due to high-volume logging. This generally should not be enabled in production unless you have a specific reason for doing so.

Parameters
boolean verboseLoggingEnabled

true to enable logging; false to disable it

setViewCacheExtension

Added in 1.0.0
public void setViewCacheExtension(
    @Nullable RecyclerView.ViewCacheExtension extension
)

Sets a new ViewCacheExtension to be used by the Recycler.

Parameters
@Nullable RecyclerView.ViewCacheExtension extension

ViewCacheExtension to be used or null if you want to clear the existing one.

smoothScrollBy

Added in 1.0.0
public void smoothScrollBy(@Px int dx, @Px int dy)

Animate a scroll by the given amount of pixels along either axis.

Parameters
@Px int dx

Pixels to scroll horizontally

@Px int dy

Pixels to scroll vertically

smoothScrollBy

Added in 1.0.0
public void smoothScrollBy(@Px int dx, @Px int dy, @Nullable Interpolator interpolator)

Animate a scroll by the given amount of pixels along either axis.

Parameters
@Px int dx

Pixels to scroll horizontally

@Px int dy

Pixels to scroll vertically

@Nullable Interpolator interpolator

Interpolator to be used for scrolling. If it is null, RecyclerView will use an internal default interpolator.

smoothScrollBy

Added in 1.1.0
public void smoothScrollBy(
    @Px int dx,
    @Px int dy,
    @Nullable Interpolator interpolator,
    int duration
)

Smooth scrolls the RecyclerView by a given distance.

Parameters
@Px int dx

x distance in pixels.

@Px int dy

y distance in pixels.

@Nullable Interpolator interpolator

Interpolator to be used for scrolling. If it is null, RecyclerView will use an internal default interpolator.

int duration

Duration of the animation in milliseconds. Set to UNDEFINED_DURATION to have the duration be automatically calculated based on an internally defined standard initial velocity. A duration less than 1 (that does not equal UNDEFINED_DURATION), will result in a call to scrollBy.

smoothScrollToPosition

Added in 1.0.0
public void smoothScrollToPosition(int position)

Starts a smooth scroll to an adapter position.

To support smooth scrolling, you must override smoothScrollToPosition and create a SmoothScroller.

LayoutManager is responsible for creating the actual scroll action. If you want to provide a custom smooth scroll logic, override smoothScrollToPosition in your LayoutManager.

Parameters
int position

The adapter position to scroll to

startNestedScroll

public boolean startNestedScroll(int axes)

startNestedScroll

Added in 1.0.0
public boolean startNestedScroll(int axes, int type)

Begin a nestable scroll operation along the given axes, for the given input type.

A view starting a nested scroll promises to abide by the following contract:

The view will call startNestedScroll upon initiating a scroll operation. In the case of a touch scroll type this corresponds to the initial ACTION_DOWN. In the case of touch scrolling the nested scroll will be terminated automatically in the same manner as requestDisallowInterceptTouchEvent. In the event of programmatic scrolling the caller must explicitly call stopNestedScroll to indicate the end of the nested scroll.

If startNestedScroll returns true, a cooperative parent was found. If it returns false the caller may ignore the rest of this contract until the next scroll. Calling startNestedScroll while a nested scroll is already in progress will return true.

At each incremental step of the scroll the caller should invoke dispatchNestedPreScroll once it has calculated the requested scrolling delta. If it returns true the nested scrolling parent at least partially consumed the scroll and the caller should adjust the amount it scrolls by.

After applying the remainder of the scroll delta the caller should invoke dispatchNestedScroll, passing both the delta consumed and the delta unconsumed. A nested scrolling parent may treat these values differently. See onNestedScroll.

Parameters
int axes

Flags consisting of a combination of SCROLL_AXIS_HORIZONTAL and/or SCROLL_AXIS_VERTICAL.

int type

the type of input which cause this scroll event

Returns
boolean

true if a cooperative parent was found and nested scrolling has been enabled for the current gesture.

stopNestedScroll

public void stopNestedScroll()

stopNestedScroll

Added in 1.0.0
public void stopNestedScroll(int type)

Stop a nested scroll in progress for the given input type.

Calling this method when a nested scroll is not currently in progress is harmless.

Parameters
int type

the type of input which cause this scroll event

stopScroll

Added in 1.0.0
public void stopScroll()

Stop any current scroll in progress, such as one started by smoothScrollBy, fling or a touch-initiated fling.

suppressLayout

Added in 1.1.0
public final void suppressLayout(boolean suppress)

Tells this RecyclerView to suppress all layout and scroll calls until layout suppression is disabled with a later call to suppressLayout(false). When layout suppression is disabled, a requestLayout() call is sent if requestLayout() was attempted while layout was being suppressed.

In addition to the layout suppression smoothScrollBy, scrollBy, scrollToPosition and smoothScrollToPosition are dropped; TouchEvents and GenericMotionEvents are dropped; onFocusSearchFailed will not be called.

suppressLayout(true) does not prevent app from directly calling scrollToPosition, smoothScrollToPosition.

setAdapter and swapAdapter will automatically stop suppressing.

Note: Running ItemAnimator is not stopped automatically, it's caller's responsibility to call ItemAnimator.end().

Parameters
boolean suppress

true to suppress layout and scroll, false to re-enable.

swapAdapter

Added in 1.0.0
public void swapAdapter(
    @Nullable RecyclerView.Adapter adapter,
    boolean removeAndRecycleExistingViews
)

Swaps the current adapter with the provided one. It is similar to setAdapter but assumes existing adapter and the new adapter uses the same ViewHolder and does not clear the RecycledViewPool.

Note that it still calls onAdapterChanged callbacks.

Parameters
@Nullable RecyclerView.Adapter adapter

The new adapter to set, or null to set no adapter.

boolean removeAndRecycleExistingViews

If set to true, RecyclerView will recycle all existing Views. If adapters have stable ids and/or you want to animate the disappearing views, you may prefer to set this to false.

See also
setAdapter

Protected methods

checkLayoutParams

protected boolean checkLayoutParams(ViewGroup.LayoutParams p)

dispatchRestoreInstanceState

protected void dispatchRestoreInstanceState(SparseArray<Parcelable> container)

Override to prevent thawing of any views created by the adapter.

dispatchSaveInstanceState

protected void dispatchSaveInstanceState(SparseArray<Parcelable> container)

Override to prevent freezing of any views created by the adapter.

generateDefaultLayoutParams

protected ViewGroup.LayoutParams generateDefaultLayoutParams()

getChildDrawingOrder

protected int getChildDrawingOrder(int childCount, int i)

onAttachedToWindow

protected void onAttachedToWindow()

onDetachedFromWindow

protected void onDetachedFromWindow()

onLayout

protected void onLayout(boolean changed, int l, int t, int r, int b)

onMeasure

protected void onMeasure(int widthSpec, int heightSpec)

onRequestFocusInDescendants

protected boolean onRequestFocusInDescendants(int direction, Rect previouslyFocusedRect)

onRestoreInstanceState

protected void onRestoreInstanceState(Parcelable state)

onSaveInstanceState

protected Parcelable onSaveInstanceState()

onSizeChanged

protected void onSizeChanged(int w, int h, int oldw, int oldh)

removeDetachedView

protected void removeDetachedView(View child, boolean animate)