FragmentStateAdapter

abstract class FragmentStateAdapter : RecyclerView.Adapter<FragmentViewHolder!>, StatefulAdapter

kotlin.Any
↳	androidx.recyclerview.widget.RecyclerView.Adapter<androidx.viewpager2.adapter.FragmentViewHolder>
	↳	androidx.viewpager2.adapter.FragmentStateAdapter

Similar in behavior to FragmentStatePagerAdapter

Lifecycle within RecyclerView:

• RecyclerView.ViewHolder initially an empty FrameLayout, serves as a re-usable container for a Fragment in later stages.
• RecyclerView.Adapter#onBindViewHolder we ask for a Fragment for the position. If we already have the fragment, or have previously saved its state, we use those.
• RecyclerView.Adapter#onAttachedToWindow we attach the Fragment to a container.
• RecyclerView.Adapter#onViewRecycled we remove, save state, destroy the Fragment.

Summary

Nested classes
abstract	FragmentTransactionCallback Callback interface for listening to fragment lifecycle changes that happen inside the adapter.

Public constructors
<init>(@NonNull fragmentActivity: FragmentActivity)
<init>(@NonNull fragment: Fragment)
<init>(@NonNull fragmentManager: FragmentManager, @NonNull lifecycle: Lifecycle)

Public methods
open Boolean	containsItem(itemId: Long) Default implementation works for collections that don't add, move, remove items.
abstract Fragment	createFragment(position: Int) Provide a new Fragment associated with the specified position.
open Long	getItemId(position: Int) Default implementation works for collections that don't add, move, remove items.
open Unit	onAttachedToRecyclerView(@NonNull recyclerView: RecyclerView)
Unit	onBindViewHolder(@NonNull holder: FragmentViewHolder, position: Int)
FragmentViewHolder	onCreateViewHolder(@NonNull parent: ViewGroup, viewType: Int)
open Unit	onDetachedFromRecyclerView(@NonNull recyclerView: RecyclerView)
Boolean	onFailedToRecycleView(@NonNull holder: FragmentViewHolder)
Unit	onViewAttachedToWindow(@NonNull holder: FragmentViewHolder)
Unit	onViewRecycled(@NonNull holder: FragmentViewHolder)
open Unit	registerFragmentTransactionCallback(@NonNull callback: FragmentStateAdapter.FragmentTransactionCallback) Registers a FragmentTransactionCallback to listen to fragment lifecycle changes that happen inside the adapter.
Unit	restoreState(@NonNull savedState: Parcelable)
Parcelable	saveState()
Unit	setHasStableIds(hasStableIds: Boolean)
open Unit	unregisterFragmentTransactionCallback(@NonNull callback: FragmentStateAdapter.FragmentTransactionCallback) Unregisters a FragmentTransactionCallback.

Inherited functions

From class Adapter Unit bindViewHolder(@NonNull holder: VH, position: Int) This method internally calls onBindViewHolder(ViewHolder, int) to update the ViewHolder contents with the item at the given position and also sets up some private fields to be used by RecyclerView. Adapters that merge other adapters should use bindViewHolder(ViewHolder, int) when calling nested adapters so that RecyclerView can track which adapter bound the ViewHolder to return the correct position from ViewHolder#getBindingAdapterPosition() method. They should also override the findRelativeAdapterPositionIn(Adapter, ViewHolder, int) method.