# ItemBridgeAdapter
# ItemBridgeAdapter
Artifact:[androidx.leanback:leanback](https://developer.android.com/jetpack/androidx/releases/leanback)
[View Source](https://cs.android.com/search?q=file:androidx/leanback/widget/ItemBridgeAdapter.java+class:androidx.leanback.widget.ItemBridgeAdapter)
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
*** ** * ** ***
Kotlin\|[Java](https://developer.android.com/reference/androidx/leanback/widget/ItemBridgeAdapter "View this page in Java")
```
class ItemBridgeAdapter : RecyclerView.Adapter, FacetProviderAdapter
```
|---|---|-----------------------------------------------------------------------------------------------------------------------------------------|
| [kotlin.Any](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-any/index.html) |||
| ↳ | [androidx.recyclerview.widget.RecyclerView.Adapter](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter) ||
| | ↳ | [androidx.leanback.widget.ItemBridgeAdapter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter) |
*** ** * ** ***
Bridge from[Presenter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/Presenter)to[RecyclerView.Adapter](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter). Public to allow use by third party Presenters.
## Summary
| ### Nested types |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `class `[ItemBridgeAdapter.AdapterListener](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter.AdapterListener) Interface for listening to ViewHolder operations. |
| `class `[ItemBridgeAdapter.ViewHolder](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter.ViewHolder)` : `[RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`, `[FacetProvider](https://developer.android.com/reference/kotlin/androidx/leanback/widget/FacetProvider) ViewHolder for the ItemBridgeAdapter. |
| `abstract class `[ItemBridgeAdapter.Wrapper](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter.Wrapper) Interface for wrapping a view created by a Presenter into another view. |
| ### Public constructors |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [ItemBridgeAdapter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#ItemBridgeAdapter())`()` |
| [ItemBridgeAdapter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#ItemBridgeAdapter(androidx.leanback.widget.ObjectAdapter))`(adapter: `[ObjectAdapter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ObjectAdapter)`!)` |
| [ItemBridgeAdapter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#ItemBridgeAdapter(androidx.leanback.widget.ObjectAdapter,androidx.leanback.widget.PresenterSelector))`(` ` adapter: `[ObjectAdapter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ObjectAdapter)`!,` ` presenterSelector: `[PresenterSelector](https://developer.android.com/reference/kotlin/androidx/leanback/widget/PresenterSelector)`!` `)` |
| ### Public functions |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [clear](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#clear())`()` Clears the adapter. |
| [FacetProvider](https://developer.android.com/reference/kotlin/androidx/leanback/widget/FacetProvider)`!` | [getFacetProvider](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#getFacetProvider(int))`(type: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`)` Queries[FacetProvider](https://developer.android.com/reference/kotlin/androidx/leanback/widget/FacetProvider)for a given type within Adapter. |
| [Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html) | [getItemCount](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#getItemCount())`()` Returns the total number of items in the data set held by the adapter. |
| [Long](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-long/index.html) | [getItemId](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#getItemId(int))`(position: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`)` Return the stable ID for the item at`position`. |
| [Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html) | [getItemViewType](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#getItemViewType(int))`(position: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`)` Return the view type of the item at`position`for the purposes of view recycling. |
| [ArrayList](https://developer.android.com/reference/java/util/ArrayList.html)`<`[Presenter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/Presenter)`!>!` | [getPresenterMapper](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#getPresenterMapper())`()` Returns the presenter mapper array. |
| [ItemBridgeAdapter.Wrapper](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter.Wrapper)`!` | [getWrapper](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#getWrapper())`()` Returns the[Wrapper](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter.Wrapper). |
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [onBindViewHolder](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#onBindViewHolder(androidx.recyclerview.widget.RecyclerView.ViewHolder,int))`(holder: `[RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`!, position: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`)` Called by RecyclerView to display the data at the specified position. |
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [onBindViewHolder](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#onBindViewHolder(androidx.recyclerview.widget.RecyclerView.ViewHolder,int,java.util.List))`(` ` holder: `[RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`!,` ` position: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`,` ` payloads: (`[Mutable](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-mutable-list/index.html)`)`[List](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-list/index.html)`!` `)` Called by RecyclerView to display the data at the specified position. |
| [RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`!` | [onCreateViewHolder](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#onCreateViewHolder(android.view.ViewGroup,int))`(parent: `[ViewGroup](https://developer.android.com/reference/android/view/ViewGroup.html)`!, viewType: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`)` [View.OnFocusChangeListener](https://developer.android.com/reference/android/view/View.OnFocusChangeListener.html)that assigned in[onCreateViewHolder](https://developer.android.com/reference/kotlin/androidx/leanback/widget/Presenter#onCreateViewHolder(android.view.ViewGroup))may be chained, user should never change[View.OnFocusChangeListener](https://developer.android.com/reference/android/view/View.OnFocusChangeListener.html)after that. |
| [Boolean](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-boolean/index.html) | [onFailedToRecycleView](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#onFailedToRecycleView(androidx.recyclerview.widget.RecyclerView.ViewHolder))`(holder: `[RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`!)` Called by the RecyclerView if a ViewHolder created by this Adapter cannot be recycled due to its transient state. |
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [onViewAttachedToWindow](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#onViewAttachedToWindow(androidx.recyclerview.widget.RecyclerView.ViewHolder))`(holder: `[RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`!)` Called when a view created by this adapter has been attached to a window. |
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [onViewDetachedFromWindow](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#onViewDetachedFromWindow(androidx.recyclerview.widget.RecyclerView.ViewHolder))`(holder: `[RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`!)` Called when a view created by this adapter has been detached from its window. |
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [onViewRecycled](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#onViewRecycled(androidx.recyclerview.widget.RecyclerView.ViewHolder))`(holder: `[RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`!)` Called when a view created by this adapter has been recycled. |
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [setAdapter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#setAdapter(androidx.leanback.widget.ObjectAdapter))`(adapter: `[ObjectAdapter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ObjectAdapter)`!)` Sets the[ObjectAdapter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ObjectAdapter). |
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [setAdapterListener](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#setAdapterListener(androidx.leanback.widget.ItemBridgeAdapter.AdapterListener))`(listener: `[ItemBridgeAdapter.AdapterListener](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter.AdapterListener)`!)` Sets the AdapterListener. |
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [setPresenter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#setPresenter(androidx.leanback.widget.PresenterSelector))`(presenterSelector: `[PresenterSelector](https://developer.android.com/reference/kotlin/androidx/leanback/widget/PresenterSelector)`!)` Changes Presenter that creates and binds the view. |
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [setPresenterMapper](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#setPresenterMapper(java.util.ArrayList))`(presenters: `[ArrayList](https://developer.android.com/reference/java/util/ArrayList.html)`<`[Presenter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/Presenter)`!>!)` Sets the presenter mapper array. |
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [setWrapper](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#setWrapper(androidx.leanback.widget.ItemBridgeAdapter.Wrapper))`(wrapper: `[ItemBridgeAdapter.Wrapper](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter.Wrapper)`!)` Sets the[Wrapper](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter.Wrapper). |
| ### Protected functions |
|-------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [onAddPresenter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#onAddPresenter(androidx.leanback.widget.Presenter,int))`(presenter: `[Presenter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/Presenter)`!, type: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`)` Called when presenter is added to Adapter. |
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [onAttachedToWindow](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#onAttachedToWindow(androidx.leanback.widget.ItemBridgeAdapter.ViewHolder))`(viewHolder: `[ItemBridgeAdapter.ViewHolder](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter.ViewHolder)`!)` Called when ViewHolder has been attached to window. |
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [onBind](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#onBind(androidx.leanback.widget.ItemBridgeAdapter.ViewHolder))`(viewHolder: `[ItemBridgeAdapter.ViewHolder](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter.ViewHolder)`!)` Called when ViewHolder has been bound to data. |
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [onCreate](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#onCreate(androidx.leanback.widget.ItemBridgeAdapter.ViewHolder))`(viewHolder: `[ItemBridgeAdapter.ViewHolder](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter.ViewHolder)`!)` Called when ViewHolder is created. |
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [onDetachedFromWindow](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#onDetachedFromWindow(androidx.leanback.widget.ItemBridgeAdapter.ViewHolder))`(viewHolder: `[ItemBridgeAdapter.ViewHolder](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter.ViewHolder)`!)` Called when ViewHolder has been detached from window. |
| [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [onUnbind](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter#onUnbind(androidx.leanback.widget.ItemBridgeAdapter.ViewHolder))`(viewHolder: `[ItemBridgeAdapter.ViewHolder](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter.ViewHolder)`!)` Called when ViewHolder has been unbound from data. |
| ### Inherited functions |
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| From[androidx.recyclerview.widget.RecyclerView.Adapter](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter) |------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [bindViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#bindViewHolder(VH,int))`(holder: VH, position: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`)` This method internally calls[onBindViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#onBindViewHolder(VH,int))to update the[ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)contents with the item at the given position and also sets up some private fields to be used by RecyclerView. | | `VH` | [createViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#createViewHolder(android.view.ViewGroup,int))`(parent: `[ViewGroup](https://developer.android.com/reference/android/view/ViewGroup.html)`, viewType: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`)` This method calls[onCreateViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#onCreateViewHolder(android.view.ViewGroup,int))to create a new[ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)and initializes some private fields to be used by RecyclerView. | | [Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html) | [findRelativeAdapterPositionIn](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#findRelativeAdapterPositionIn(androidx.recyclerview.widget.RecyclerView.Adapter,androidx.recyclerview.widget.RecyclerView.ViewHolder,int))`(` ` adapter: `[RecyclerView.Adapter](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter)`<`[RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`!>,` ` viewHolder: `[RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`,` ` localPosition: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html) `)` Returns the position of the given[ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)in the given[Adapter](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter). | | [RecyclerView.Adapter.StateRestorationPolicy](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter.StateRestorationPolicy) | [getStateRestorationPolicy](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#getStateRestorationPolicy())`()` Returns when this Adapter wants to restore the state. | | [Boolean](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-boolean/index.html) | [hasObservers](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#hasObservers())`()` Returns true if one or more observers are attached to this adapter. | | [Boolean](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-boolean/index.html) | [hasStableIds](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#hasStableIds())`()` Returns true if this adapter publishes a unique`long`value that can act as a key for the item at a given position in the data set. | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [notifyDataSetChanged](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#notifyDataSetChanged())`()` Notify any registered observers that the data set has changed. | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [notifyItemChanged](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#notifyItemChanged(int))`(position: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`)` Notify any registered observers that the item at`position`has changed. | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [notifyItemChanged](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#notifyItemChanged(int,java.lang.Object))`(position: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`, payload: `[Any](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-any/index.html)`?)` Notify any registered observers that the item at`position`has changed with an optional payload object. | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [notifyItemInserted](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#notifyItemInserted(int))`(position: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`)` Notify any registered observers that the item reflected at`position`has been newly inserted. | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [notifyItemMoved](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#notifyItemMoved(int,int))`(fromPosition: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`, toPosition: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`)` Notify any registered observers that the item reflected at`fromPosition`has been moved to`toPosition`. | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [notifyItemRangeChanged](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#notifyItemRangeChanged(int,int))`(positionStart: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`, itemCount: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`)` Notify any registered observers that the`itemCount`items starting at position`positionStart`have changed. | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [notifyItemRangeChanged](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#notifyItemRangeChanged(int,int,java.lang.Object))`(positionStart: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`, itemCount: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`, payload: `[Any](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-any/index.html)`?)` Notify any registered observers that the`itemCount`items starting at position`positionStart`have changed. | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [notifyItemRangeInserted](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#notifyItemRangeInserted(int,int))`(positionStart: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`, itemCount: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`)` Notify any registered observers that the currently reflected`itemCount`items starting at`positionStart`have been newly inserted. | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [notifyItemRangeRemoved](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#notifyItemRangeRemoved(int,int))`(positionStart: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`, itemCount: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`)` Notify any registered observers that the`itemCount`items previously located at`positionStart`have been removed from the data set. | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [notifyItemRemoved](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#notifyItemRemoved(int))`(position: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html)`)` Notify any registered observers that the item previously located at`position`has been removed from the data set. | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [onAttachedToRecyclerView](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#onAttachedToRecyclerView(androidx.recyclerview.widget.RecyclerView))`(recyclerView: `[RecyclerView](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView)`)` Called by RecyclerView when it starts observing this Adapter. | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [onDetachedFromRecyclerView](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#onDetachedFromRecyclerView(androidx.recyclerview.widget.RecyclerView))`(recyclerView: `[RecyclerView](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView)`)` Called by RecyclerView when it stops observing this Adapter. | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [registerAdapterDataObserver](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#registerAdapterDataObserver(androidx.recyclerview.widget.RecyclerView.AdapterDataObserver))`(observer: `[RecyclerView.AdapterDataObserver](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.AdapterDataObserver)`)` Register a new observer to listen for data changes. | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [setHasStableIds](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#setHasStableIds(boolean))`(hasStableIds: `[Boolean](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-boolean/index.html)`)` Indicates whether each item in the data set can be represented with a unique identifier of type[java.lang.Long](https://developer.android.com/reference/java/lang/Long.html). | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [setStateRestorationPolicy](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#setStateRestorationPolicy(androidx.recyclerview.widget.RecyclerView.Adapter.StateRestorationPolicy))`(` ` strategy: `[RecyclerView.Adapter.StateRestorationPolicy](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter.StateRestorationPolicy) `)` Sets the state restoration strategy for the Adapter. | | [Unit](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html) | [unregisterAdapterDataObserver](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#unregisterAdapterDataObserver(androidx.recyclerview.widget.RecyclerView.AdapterDataObserver))`(` ` observer: `[RecyclerView.AdapterDataObserver](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.AdapterDataObserver) `)` Unregister an observer currently listening for data changes. | |
## Public constructors
### ItemBridgeAdapter
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
ItemBridgeAdapter()
```
### ItemBridgeAdapter
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
ItemBridgeAdapter(adapter: ObjectAdapter!)
```
### ItemBridgeAdapter
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
ItemBridgeAdapter(
adapter: ObjectAdapter!,
presenterSelector: PresenterSelector!
)
```
## Public functions
### clear
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun clear(): Unit
```
Clears the adapter.
### getFacetProvider
```
fun getFacetProvider(type: Int): FacetProvider!
```
Queries[FacetProvider](https://developer.android.com/reference/kotlin/androidx/leanback/widget/FacetProvider)for a given type within Adapter.
| Parameters |
|-------------------------------------------------------------------------------------|-------------------|
| `type: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html) | type of the item. |
| Returns |
|-----------------------------------------------------------------------------------------------------------|------------------------------|
| [FacetProvider](https://developer.android.com/reference/kotlin/androidx/leanback/widget/FacetProvider)`!` | Facet provider for the type. |
### getItemCount
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun getItemCount(): Int
```
Returns the total number of items in the data set held by the adapter.
| Returns |
|-----------------------------------------------------------------------------|--------------------------------------------|
| [Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html) | The total number of items in this adapter. |
### getItemId
```
fun getItemId(position: Int): Long
```
Return the stable ID for the item at`position`. If[hasStableIds](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#hasStableIds())would return false this method should return[NO_ID](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView#NO_ID()). The default implementation of this method returns[NO_ID](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView#NO_ID()).
| Parameters |
|-----------------------------------------------------------------------------------------|---------------------------|
| `position: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html) | Adapter position to query |
| Returns |
|-------------------------------------------------------------------------------|---------------------------------------|
| [Long](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-long/index.html) | the stable ID of the item at position |
### getItemViewType
```
fun getItemViewType(position: Int): Int
```
Return the view type of the item at`position`for the purposes of view recycling.
The default implementation of this method returns 0, making the assumption of a single view type for the adapter. Unlike ListView adapters, types need not be contiguous. Consider using id resources to uniquely identify item view types.
| Parameters |
|-----------------------------------------------------------------------------------------|-------------------|
| `position: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html) | position to query |
| Returns |
|-----------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------|
| [Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html) | integer value identifying the type of the view needed to represent the item at`position`. Type codes need not be contiguous. |
### getPresenterMapper
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun getPresenterMapper(): ArrayList!
```
Returns the presenter mapper array.
### getWrapper
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun getWrapper(): ItemBridgeAdapter.Wrapper!
```
Returns the[Wrapper](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter.Wrapper).
### onBindViewHolder
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun onBindViewHolder(holder: RecyclerView.ViewHolder!, position: Int): Unit
```
Called by RecyclerView to display the data at the specified position. This method should update the contents of the[itemView](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder#itemView())to reflect the item at the given position.
Note that unlike[android.widget.ListView](https://developer.android.com/reference/android/widget/ListView.html), RecyclerView will not call this method again if the position of the item changes in the data set unless the item itself is invalidated or the new position cannot be determined. For this reason, you should only use the`position`parameter while acquiring the related data item inside this method and should not keep a copy of it. If you need the position of an item later on (e.g. in a click listener), use[getBindingAdapterPosition](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder#getBindingAdapterPosition())which will have the updated adapter position. Override[onBindViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#onBindViewHolder(VH,int,java.util.List))instead if Adapter can handle efficient partial bind.
| Parameters |
|---------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------|
| `holder: `[RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`!` | The ViewHolder which should be updated to represent the contents of the item at the given position in the data set. |
| `position: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html) | The position of the item within the adapter's data set. |
### onBindViewHolder
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun onBindViewHolder(
holder: RecyclerView.ViewHolder!,
position: Int,
payloads: (Mutable)List!
): Unit
```
Called by RecyclerView to display the data at the specified position. This method should update the contents of the[itemView](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder#itemView())to reflect the item at the given position.
Note that unlike[android.widget.ListView](https://developer.android.com/reference/android/widget/ListView.html), RecyclerView will not call this method again if the position of the item changes in the data set unless the item itself is invalidated or the new position cannot be determined. For this reason, you should only use the`position`parameter while acquiring the related data item inside this method and should not keep a copy of it. If you need the position of an item later on (e.g. in a click listener), use[getBindingAdapterPosition](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder#getBindingAdapterPosition())which will have the updated adapter position.
Partial bind vs full bind:
The payloads parameter is a merge list from[notifyItemChanged](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#notifyItemChanged(int,java.lang.Object))or[notifyItemRangeChanged](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#notifyItemRangeChanged(int,int,java.lang.Object)). If the payloads list is not empty, the ViewHolder is currently bound to old data and Adapter may run an efficient partial update using the payload info. If the payload is empty, Adapter must run a full bind. Adapter should not assume that the payload passed in notify methods will be received by onBindViewHolder(). For example when the view is not attached to the screen, the payload in notifyItemChange() will be simply dropped.
| Parameters |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------|
| `holder: `[RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`!` | The ViewHolder which should be updated to represent the contents of the item at the given position in the data set. |
| `position: `[Int](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html) | The position of the item within the adapter's data set. |
| `payloads: (`[Mutable](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-mutable-list/index.html)`)`[List](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-list/index.html)`!` | A non-null list of merged payloads. Can be empty list if requires full update. |
### onCreateViewHolder
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun onCreateViewHolder(parent: ViewGroup!, viewType: Int): RecyclerView.ViewHolder!
```
[View.OnFocusChangeListener](https://developer.android.com/reference/android/view/View.OnFocusChangeListener.html)that assigned in[onCreateViewHolder](https://developer.android.com/reference/kotlin/androidx/leanback/widget/Presenter#onCreateViewHolder(android.view.ViewGroup))may be chained, user should never change[View.OnFocusChangeListener](https://developer.android.com/reference/android/view/View.OnFocusChangeListener.html)after that.
### onFailedToRecycleView
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun onFailedToRecycleView(holder: RecyclerView.ViewHolder!): Boolean
```
Called by the RecyclerView if a ViewHolder created by this Adapter cannot be recycled due to its transient state. Upon receiving this callback, Adapter can clear the animation(s) that effect the View's transient state and return`true`so that the View can be recycled. Keep in mind that the View in question is already removed from the RecyclerView.
In some cases, it is acceptable to recycle a View although it has transient state. Most of the time, this is a case where the transient state will be cleared in[onBindViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#onBindViewHolder(VH,int))call when View is rebound to a new position. For this reason, RecyclerView leaves the decision to the Adapter and uses the return value of this method to decide whether the View should be recycled or not.
Note that when all animations are created by[RecyclerView.ItemAnimator](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ItemAnimator), you should never receive this callback because RecyclerView keeps those Views as children until their animations are complete. This callback is useful when children of the item views create animations which may not be easy to implement using an[ItemAnimator](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ItemAnimator).
You should*never* fix this issue by calling`holder.itemView.setHasTransientState(false);`unless you've previously called`holder.itemView.setHasTransientState(true);`. Each`View.setHasTransientState(true)`call must be matched by a`View.setHasTransientState(false)`call, otherwise, the state of the View may become inconsistent. You should always prefer to end or cancel animations that are triggering the transient state instead of handling it manually.
| Parameters |
|---------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------|
| `holder: `[RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`!` | The ViewHolder containing the View that could not be recycled due to its transient state. |
| Returns |
|-------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [Boolean](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-boolean/index.html) | True if the View should be recycled, false otherwise. Note that if this method returns`true`, RecyclerView*will ignore* the transient state of the View and recycle it regardless. If this method returns`false`, RecyclerView will check the View's transient state again before giving a final decision. Default implementation returns false. |
### onViewAttachedToWindow
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun onViewAttachedToWindow(holder: RecyclerView.ViewHolder!): Unit
```
Called when a view created by this adapter has been attached to a window.
This can be used as a reasonable signal that the view is about to be seen by the user. If the adapter previously freed any resources in[onViewDetachedFromWindow](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.Adapter#onViewDetachedFromWindow(VH))those resources should be restored here.
| Parameters |
|---------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------|
| `holder: `[RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`!` | Holder of the view being attached |
### onViewDetachedFromWindow
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun onViewDetachedFromWindow(holder: RecyclerView.ViewHolder!): Unit
```
Called when a view created by this adapter has been detached from its window.
Becoming detached from the window is not necessarily a permanent condition; the consumer of an Adapter's views may choose to cache views offscreen while they are not visible, attaching and detaching them as appropriate.
| Parameters |
|---------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------|
| `holder: `[RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`!` | Holder of the view being detached |
### onViewRecycled
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun onViewRecycled(holder: RecyclerView.ViewHolder!): Unit
```
Called when a view created by this adapter has been recycled.
A view is recycled when a[LayoutManager](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.LayoutManager)decides that it no longer needs to be attached to its parent[RecyclerView](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView). This can be because it has fallen out of visibility or a set of cached views represented by views still attached to the parent RecyclerView. If an item view has large or expensive data bound to it such as large bitmaps, this may be a good place to release those resources.
RecyclerView calls this method right before clearing ViewHolder's internal data and sending it to RecycledViewPool. This way, if ViewHolder was holding valid information before being recycled, you can call[getBindingAdapterPosition](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder#getBindingAdapterPosition())to get its adapter position.
| Parameters |
|---------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------|
| `holder: `[RecyclerView.ViewHolder](https://developer.android.com/reference/kotlin/androidx/recyclerview/widget/RecyclerView.ViewHolder)`!` | The ViewHolder for the view being recycled |
### setAdapter
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun setAdapter(adapter: ObjectAdapter!): Unit
```
Sets the[ObjectAdapter](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ObjectAdapter).
### setAdapterListener
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun setAdapterListener(listener: ItemBridgeAdapter.AdapterListener!): Unit
```
Sets the AdapterListener.
### setPresenter
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun setPresenter(presenterSelector: PresenterSelector!): Unit
```
Changes Presenter that creates and binds the view.
| Parameters |
|----------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------|
| `presenterSelector: `[PresenterSelector](https://developer.android.com/reference/kotlin/androidx/leanback/widget/PresenterSelector)`!` | Presenter that creates and binds the view. |
### setPresenterMapper
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun setPresenterMapper(presenters: ArrayList!): Unit
```
Sets the presenter mapper array.
### setWrapper
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
fun setWrapper(wrapper: ItemBridgeAdapter.Wrapper!): Unit
```
Sets the[Wrapper](https://developer.android.com/reference/kotlin/androidx/leanback/widget/ItemBridgeAdapter.Wrapper).
## Protected functions
### onAddPresenter
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
protected fun onAddPresenter(presenter: Presenter!, type: Int): Unit
```
Called when presenter is added to Adapter.
### onAttachedToWindow
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
protected fun onAttachedToWindow(viewHolder: ItemBridgeAdapter.ViewHolder!): Unit
```
Called when ViewHolder has been attached to window.
### onBind
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
protected fun onBind(viewHolder: ItemBridgeAdapter.ViewHolder!): Unit
```
Called when ViewHolder has been bound to data.
### onCreate
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
protected fun onCreate(viewHolder: ItemBridgeAdapter.ViewHolder!): Unit
```
Called when ViewHolder is created.
### onDetachedFromWindow
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
protected fun onDetachedFromWindow(viewHolder: ItemBridgeAdapter.ViewHolder!): Unit
```
Called when ViewHolder has been detached from window.
### onUnbind
Added in[1.1.0](https://developer.android.com/jetpack/androidx/releases/leanback#1.1.0)
```
protected fun onUnbind(viewHolder: ItemBridgeAdapter.ViewHolder!): Unit
```
Called when ViewHolder has been unbound from data.