SimpleItemAnimator

Kotlin |Java

abstract class SimpleItemAnimator : RecyclerView.ItemAnimator

kotlin.Any
↳	androidx.recyclerview.widget.RecyclerView.ItemAnimator
	↳	androidx.recyclerview.widget.SimpleItemAnimator

Known Direct Subclasses DefaultItemAnimator DefaultItemAnimator This implementation of RecyclerView.ItemAnimator provides basic animations on remove, add, and move events that happen to the items in a RecyclerView.

A wrapper class for ItemAnimator that records View bounds and decides whether it should run move, change, add or remove animations. This class also replicates the original ItemAnimator API.

It uses RecyclerView.ItemAnimator.ItemHolderInfo to track the bounds information of the Views. If you would like to extend this class, you can override obtainHolderInfo() method to provide your own info class that extends RecyclerView.ItemAnimator.ItemHolderInfo.

Summary

Inherited constants

From class ItemAnimator Int FLAG_APPEARED_IN_PRE_LAYOUT This ViewHolder was not laid out but has been added to the layout in pre-layout state by the LayoutManager. This means that the item was already in the Adapter but invisible and it may become visible in the post layout phase. LayoutManagers may prefer to add new items in pre-layout to specify their virtual location when they are invisible (e.g. to specify the item should animate in from below the visible area). Int FLAG_CHANGED The Item represented by this ViewHolder is updated. Int FLAG_INVALIDATED Adapter Adapter#notifyDataSetChanged() has been called and the content represented by this ViewHolder is invalid. Int FLAG_MOVED The position of the Item represented by this ViewHolder has been changed. This flag is not bound to Adapter#notifyItemMoved(int, int). It might be set in response to any adapter change that may have a side effect on this item. (e.g. The item before this one has been removed from the Adapter). Int FLAG_REMOVED The Item represented by this ViewHolder is removed from the adapter.

Public constructors
<init>() A wrapper class for ItemAnimator that records View bounds and decides whether it should run move, change, add or remove animations.

Public methods
abstract Boolean	animateAdd(holder: RecyclerView.ViewHolder!) Called when an item is added to the RecyclerView.
open Boolean	animateAppearance(@NonNull viewHolder: RecyclerView.ViewHolder, @Nullable preLayoutInfo: RecyclerView.ItemAnimator.ItemHolderInfo?, @NonNull postLayoutInfo: RecyclerView.ItemAnimator.ItemHolderInfo)
open Boolean	animateChange(@NonNull oldHolder: RecyclerView.ViewHolder, @NonNull newHolder: RecyclerView.ViewHolder, @NonNull preInfo: RecyclerView.ItemAnimator.ItemHolderInfo, @NonNull postInfo: RecyclerView.ItemAnimator.ItemHolderInfo)
abstract Boolean	animateChange(oldHolder: RecyclerView.ViewHolder!, newHolder: RecyclerView.ViewHolder!, fromLeft: Int, fromTop: Int, toLeft: Int, toTop: Int) Called when an item is changed in the RecyclerView, as indicated by a call to RecyclerView.Adapter#notifyItemChanged(int) or RecyclerView.Adapter#notifyItemRangeChanged(int, int).
open Boolean	animateDisappearance(@NonNull viewHolder: RecyclerView.ViewHolder, @NonNull preLayoutInfo: RecyclerView.ItemAnimator.ItemHolderInfo, @Nullable postLayoutInfo: RecyclerView.ItemAnimator.ItemHolderInfo?)
abstract Boolean	animateMove(holder: RecyclerView.ViewHolder!, fromX: Int, fromY: Int, toX: Int, toY: Int) Called when an item is moved in the RecyclerView.
open Boolean	animatePersistence(@NonNull viewHolder: RecyclerView.ViewHolder, @NonNull preInfo: RecyclerView.ItemAnimator.ItemHolderInfo, @NonNull postInfo: RecyclerView.ItemAnimator.ItemHolderInfo)
abstract Boolean	animateRemove(holder: RecyclerView.ViewHolder!) Called when an item is removed from the RecyclerView.
open Boolean	canReuseUpdatedViewHolder(@NonNull viewHolder: RecyclerView.ViewHolder) When an item is changed, ItemAnimator can decide whether it wants to re-use the same ViewHolder for animations or RecyclerView should create a copy of the item and ItemAnimator will use both to run the animation (e.g. cross-fade).
Unit	dispatchAddFinished(item: RecyclerView.ViewHolder!) Method to be called by subclasses when an add animation is done.
Unit	dispatchAddStarting(item: RecyclerView.ViewHolder!) Method to be called by subclasses when an add animation is being started.
Unit	dispatchChangeFinished(item: RecyclerView.ViewHolder!, oldItem: Boolean) Method to be called by subclasses when a change animation is done.
Unit	dispatchChangeStarting(item: RecyclerView.ViewHolder!, oldItem: Boolean) Method to be called by subclasses when a change animation is being started.
Unit	dispatchMoveFinished(item: RecyclerView.ViewHolder!) Method to be called by subclasses when a move animation is done.
Unit	dispatchMoveStarting(item: RecyclerView.ViewHolder!) Method to be called by subclasses when a move animation is being started.
Unit	dispatchRemoveFinished(item: RecyclerView.ViewHolder!) Method to be called by subclasses when a remove animation is done.
Unit	dispatchRemoveStarting(item: RecyclerView.ViewHolder!) Method to be called by subclasses when a remove animation is being started.
open Boolean	getSupportsChangeAnimations() Returns whether this ItemAnimator supports animations of change events.
open Unit	onAddFinished(item: RecyclerView.ViewHolder!) Called when an add animation has ended on the given ViewHolder.
open Unit	onAddStarting(item: RecyclerView.ViewHolder!) Called when an add animation is being started on the given ViewHolder.
open Unit	onChangeFinished(item: RecyclerView.ViewHolder!, oldItem: Boolean) Called when a change animation has ended on the given ViewHolder.
open Unit	onChangeStarting(item: RecyclerView.ViewHolder!, oldItem: Boolean) Called when a change animation is being started on the given ViewHolder.
open Unit	onMoveFinished(item: RecyclerView.ViewHolder!) Called when a move animation has ended on the given ViewHolder.
open Unit	onMoveStarting(item: RecyclerView.ViewHolder!) Called when a move animation is being started on the given ViewHolder.
open Unit	onRemoveFinished(item: RecyclerView.ViewHolder!) Called when a remove animation has ended on the given ViewHolder.
open Unit	onRemoveStarting(item: RecyclerView.ViewHolder!) Called when a remove animation is being started on the given ViewHolder.
open Unit	setSupportsChangeAnimations(supportsChangeAnimations: Boolean) Sets whether this ItemAnimator supports animations of item change events.

Inherited functions

From class ItemAnimator Boolean canReuseUpdatedViewHolder(@NonNull viewHolder: RecyclerView.ViewHolder, @NonNull payloads: MutableList<Any!>) When an item is changed, ItemAnimator can decide whether it wants to re-use the same ViewHolder for animations or RecyclerView should create a copy of the item and ItemAnimator will use both to run the animation (e.g. cross-fade). Note that this method will only be called if the ViewHolder still has the same type (Adapter#getItemViewType(int)). Otherwise, ItemAnimator will always receive both ViewHolders in the animateChange(ViewHolder, ViewHolder, ItemHolderInfo, ItemHolderInfo) method. Unit dispatchAnimationFinished(@NonNull viewHolder: RecyclerView.ViewHolder) Method to be called by subclasses when an animation is finished. For each call RecyclerView makes to animateAppearance(), animatePersistence(), or animateDisappearance(), there should be a matching dispatchAnimationFinished(ViewHolder) call by the subclass. For animateChange(), subclass should call this method for both the oldHolder and newHolder (if they are not the same instance). Unit dispatchAnimationStarted(@NonNull viewHolder: RecyclerView.ViewHolder) Method to be called by subclasses when an animation is started. For each call RecyclerView makes to animateAppearance(), animatePersistence(), or animateDisappearance(), there should be a matching dispatchAnimationStarted(ViewHolder) call by the subclass. For animateChange(), subclass should call this method for both the oldHolder and newHolder (if they are not the same instance). If your ItemAnimator decides not to animate a ViewHolder, it should call dispatchAnimationFinished(ViewHolder) without calling dispatchAnimationStarted(ViewHolder). Unit dispatchAnimationsFinished() This method should be called by ItemAnimator implementations to notify any listeners that all pending and active item animations are finished. Unit endAnimation(@NonNull item: RecyclerView.ViewHolder) Method called when an animation on a view should be ended immediately. This could happen when other events, like scrolling, occur, so that animating views can be quickly put into their proper end locations. Implementations should ensure that any animations running on the item are canceled and affected properties are set to their end values. Also, dispatchAnimationFinished(ViewHolder) should be called for each finished animation since the animations are effectively done when this method is called. Unit endAnimations() Method called when all item animations should be ended immediately. This could happen when other events, like scrolling, occur, so that animating views can be quickly put into their proper end locations. Implementations should ensure that any animations running on any items are canceled and affected properties are set to their end values. Also, dispatchAnimationFinished(ViewHolder) should be called for each finished animation since the animations are effectively done when this method is called. Long getAddDuration() Gets the current duration for which all add animations will run. Long getChangeDuration() Gets the current duration for which all change animations will run. Long getMoveDuration() Gets the current duration for which all move animations will run. Long getRemoveDuration() Gets the current duration for which all remove animations will run. Boolean isRunning() Method which returns whether there are any item animations currently running. This method can be used to determine whether to delay other actions until animations end. Boolean isRunning(@Nullable listener: RecyclerView.ItemAnimator.ItemAnimatorFinishedListener?) Like isRunning(), this method returns whether there are any item animations currently running. Additionally, the listener passed in will be called when there are no item animations running, either immediately (before the method returns) if no animations are currently running, or when the currently running animations are finished. Note that the listener is transient - it is either called immediately and not stored at all, or stored only until it is called when running animations are finished sometime later. RecyclerView.ItemAnimator.ItemHolderInfo obtainHolderInfo() Returns a new ItemHolderInfo which will be used to store information about the ViewHolder. This information will later be passed into animate** methods. You can override this method if you want to extend ItemHolderInfo and provide your own instances. Unit onAnimationFinished(@NonNull viewHolder: RecyclerView.ViewHolder) Called after dispatchAnimationFinished(ViewHolder) is called by the ItemAnimator. Unit onAnimationStarted(@NonNull viewHolder: RecyclerView.ViewHolder) Called when a new animation is started on the given ViewHolder. RecyclerView.ItemAnimator.ItemHolderInfo recordPostLayoutInformation(@NonNull state: RecyclerView.State, @NonNull viewHolder: RecyclerView.ViewHolder) Called by the RecyclerView after the layout is complete. Item animator should record necessary information about the View's final state. The data returned from this method will be passed to the related animate** methods. The default implementation returns an ItemHolderInfo which holds the bounds of the View. RecyclerView.ItemAnimator.ItemHolderInfo recordPreLayoutInformation(@NonNull state: RecyclerView.State, @NonNull viewHolder: RecyclerView.ViewHolder, changeFlags: Int, @NonNull payloads: MutableList<Any!>) Called by the RecyclerView before the layout begins. Item animator should record necessary information about the View before it is potentially rebound, moved or removed. The data returned from this method will be passed to the related animate** methods. Note that this method may be called after pre-layout phase if LayoutManager adds new Views to the layout in pre-layout pass. The default implementation returns an ItemHolderInfo which holds the bounds of the View and the adapter change flags. Unit runPendingAnimations() Called when there are pending animations waiting to be started. This state is governed by the return values from animateAppearance(), animateChange() animatePersistence(), and animateDisappearance(), which inform the RecyclerView that the ItemAnimator wants to be called later to start the associated animations. runPendingAnimations() will be scheduled to be run on the next frame. Unit setAddDuration(addDuration: Long) Sets the duration for which all add animations will run. Unit setChangeDuration(changeDuration: Long) Sets the duration for which all change animations will run. Unit setMoveDuration(moveDuration: Long) Sets the duration for which all move animations will run. Unit setRemoveDuration(removeDuration: Long) Sets the duration for which all remove animations will run.

Public constructors

<init>

SimpleItemAnimator()

A wrapper class for ItemAnimator that records View bounds and decides whether it should run move, change, add or remove animations. This class also replicates the original ItemAnimator API.

It uses RecyclerView.ItemAnimator.ItemHolderInfo to track the bounds information of the Views. If you would like to extend this class, you can override obtainHolderInfo() method to provide your own info class that extends RecyclerView.ItemAnimator.ItemHolderInfo.

Public methods

animateAdd

abstract fun animateAdd(holder: RecyclerView.ViewHolder!): Boolean

Called when an item is added to the RecyclerView. Implementors can choose whether and how to animate that change, but must always call dispatchAddFinished(RecyclerView.ViewHolder) when done, either immediately (if no animation will occur) or after the animation actually finishes. The return value indicates whether an animation has been set up and whether the ItemAnimator's runPendingAnimations() method should be called at the next opportunity. This mechanism allows ItemAnimator to set up individual animations as separate calls to animateAdd(), animateMove(), animateRemove(), and animateChange(RecyclerView.ViewHolder, RecyclerView.ViewHolder, int, int, int, int) come in one by one, then start the animations together in the later call to runPendingAnimations().

This method may also be called for appearing items which were already in the RecyclerView, but for which the system does not have enough information to animate them into view. In that case, the default animation for adding items is run on those items as well.

Parameters
holder	RecyclerView.ViewHolder!: The item that is being added.

Return
Boolean	true if a later call to runPendingAnimations() is requested, false otherwise.

animateAppearance

open fun animateAppearance(
    @NonNull viewHolder: RecyclerView.ViewHolder, 
    @Nullable preLayoutInfo: RecyclerView.ItemAnimator.ItemHolderInfo?, 
    @NonNull postLayoutInfo: RecyclerView.ItemAnimator.ItemHolderInfo
): Boolean

animateChange

open fun animateChange(
    @NonNull oldHolder: RecyclerView.ViewHolder, 
    @NonNull newHolder: RecyclerView.ViewHolder, 
    @NonNull preInfo: RecyclerView.ItemAnimator.ItemHolderInfo, 
    @NonNull postInfo: RecyclerView.ItemAnimator.ItemHolderInfo
): Boolean

animateChange

abstract fun animateChange(
    oldHolder: RecyclerView.ViewHolder!, 
    newHolder: RecyclerView.ViewHolder!, 
    fromLeft: Int, 
    fromTop: Int, 
    toLeft: Int, 
    toTop: Int
): Boolean

Called when an item is changed in the RecyclerView, as indicated by a call to RecyclerView.Adapter#notifyItemChanged(int) or RecyclerView.Adapter#notifyItemRangeChanged(int, int).

Implementers can choose whether and how to animate changes, but must always call dispatchChangeFinished(RecyclerView.ViewHolder, boolean) for each non-null distinct ViewHolder, either immediately (if no animation will occur) or after the animation actually finishes. If the oldHolder is the same ViewHolder as the newHolder, you must call dispatchChangeFinished(RecyclerView.ViewHolder, boolean) once and only once. In that case, the second parameter of dispatchChangeFinished is ignored.

The return value indicates whether an animation has been set up and whether the ItemAnimator's runPendingAnimations() method should be called at the next opportunity. This mechanism allows ItemAnimator to set up individual animations as separate calls to animateAdd(), animateMove(), animateRemove(), and animateChange(RecyclerView.ViewHolder, RecyclerView.ViewHolder, int, int, int, int) come in one by one, then start the animations together in the later call to runPendingAnimations().

Parameters
oldHolder	RecyclerView.ViewHolder!: The original item that changed.
newHolder	RecyclerView.ViewHolder!: The new item that was created with the changed content. Might be null
fromLeft	Int: Left of the old view holder
fromTop	Int: Top of the old view holder
toLeft	Int: Left of the new view holder
toTop	Int: Top of the new view holder

Return
Boolean	true if a later call to runPendingAnimations() is requested, false otherwise.

animateDisappearance

open fun animateDisappearance(
    @NonNull viewHolder: RecyclerView.ViewHolder, 
    @NonNull preLayoutInfo: RecyclerView.ItemAnimator.ItemHolderInfo, 
    @Nullable postLayoutInfo: RecyclerView.ItemAnimator.ItemHolderInfo?
): Boolean

animateMove

abstract fun animateMove(
    holder: RecyclerView.ViewHolder!, 
    fromX: Int, 
    fromY: Int, 
    toX: Int, 
    toY: Int
): Boolean

Called when an item is moved in the RecyclerView. Implementors can choose whether and how to animate that change, but must always call dispatchMoveFinished(RecyclerView.ViewHolder) when done, either immediately (if no animation will occur) or after the animation actually finishes. The return value indicates whether an animation has been set up and whether the ItemAnimator's runPendingAnimations() method should be called at the next opportunity. This mechanism allows ItemAnimator to set up individual animations as separate calls to animateAdd(), animateMove(), animateRemove(), and animateChange(RecyclerView.ViewHolder, RecyclerView.ViewHolder, int, int, int, int) come in one by one, then start the animations together in the later call to runPendingAnimations().

Parameters
holder	RecyclerView.ViewHolder!: The item that is being moved.

Return
Boolean	true if a later call to runPendingAnimations() is requested, false otherwise.

animatePersistence

open fun animatePersistence(
    @NonNull viewHolder: RecyclerView.ViewHolder, 
    @NonNull preInfo: RecyclerView.ItemAnimator.ItemHolderInfo, 
    @NonNull postInfo: RecyclerView.ItemAnimator.ItemHolderInfo
): Boolean

animateRemove

abstract fun animateRemove(holder: RecyclerView.ViewHolder!): Boolean

Called when an item is removed from the RecyclerView. Implementors can choose whether and how to animate that change, but must always call dispatchRemoveFinished(RecyclerView.ViewHolder) when done, either immediately (if no animation will occur) or after the animation actually finishes. The return value indicates whether an animation has been set up and whether the ItemAnimator's runPendingAnimations() method should be called at the next opportunity. This mechanism allows ItemAnimator to set up individual animations as separate calls to animateAdd(), animateMove(), animateRemove(), and animateChange(RecyclerView.ViewHolder, RecyclerView.ViewHolder, int, int, int, int) come in one by one, then start the animations together in the later call to runPendingAnimations().

This method may also be called for disappearing items which continue to exist in the RecyclerView, but for which the system does not have enough information to animate them out of view. In that case, the default animation for removing items is run on those items as well.

Parameters
holder	RecyclerView.ViewHolder!: The item that is being removed.

Return
Boolean	true if a later call to runPendingAnimations() is requested, false otherwise.

canReuseUpdatedViewHolder

open fun canReuseUpdatedViewHolder(@NonNull viewHolder: RecyclerView.ViewHolder): Boolean

When an item is changed, ItemAnimator can decide whether it wants to re-use the same ViewHolder for animations or RecyclerView should create a copy of the item and ItemAnimator will use both to run the animation (e.g. cross-fade).

Note that this method will only be called if the ViewHolder still has the same type (Adapter#getItemViewType(int)). Otherwise, ItemAnimator will always receive both ViewHolders in the animateChange(ViewHolder, ViewHolder, ItemHolderInfo, ItemHolderInfo) method.

If your application is using change payloads, you can override canReuseUpdatedViewHolder(ViewHolder, List) to decide based on payloads.

Parameters
viewHolder	RecyclerView.ViewHolder: The ViewHolder which represents the changed item's old content.

Return
Boolean	True if change animations are not supported or the ViewHolder is invalid, false otherwise.

See Also

• #setSupportsChangeAnimations(boolean)

dispatchAddFinished

fun dispatchAddFinished(item: RecyclerView.ViewHolder!): Unit

Method to be called by subclasses when an add animation is done.

Parameters
item	RecyclerView.ViewHolder!: The item which has been added

dispatchAddStarting

fun dispatchAddStarting(item: RecyclerView.ViewHolder!): Unit

Method to be called by subclasses when an add animation is being started.

Parameters
item	RecyclerView.ViewHolder!: The item being added

dispatchChangeFinished

fun dispatchChangeFinished(
    item: RecyclerView.ViewHolder!, 
    oldItem: Boolean
): Unit

Method to be called by subclasses when a change animation is done.

Parameters
item	RecyclerView.ViewHolder!: The item which has been changed (this method must be called for each non-null ViewHolder passed into animateChange(RecyclerView.ViewHolder, RecyclerView.ViewHolder, int, int, int, int)).
oldItem	Boolean: true if this is the old item that was changed, false if it is the new item that replaced the old item.

See Also

• #animateChange(RecyclerView.ViewHolder, RecyclerView.ViewHolder, int, int, int, int)

dispatchChangeStarting

fun dispatchChangeStarting(
    item: RecyclerView.ViewHolder!, 
    oldItem: Boolean
): Unit

Method to be called by subclasses when a change animation is being started.

Parameters
item	RecyclerView.ViewHolder!: The item which has been changed (this method must be called for each non-null ViewHolder passed into animateChange(RecyclerView.ViewHolder, RecyclerView.ViewHolder, int, int, int, int)).
oldItem	Boolean: true if this is the old item that was changed, false if it is the new item that replaced the old item.

dispatchMoveFinished

fun dispatchMoveFinished(item: RecyclerView.ViewHolder!): Unit

Method to be called by subclasses when a move animation is done.

Parameters
item	RecyclerView.ViewHolder!: The item which has been moved

See Also

• RecyclerView.ItemAnimator#animateDisappearance(RecyclerView.ViewHolder, ItemHolderInfo, * ItemHolderInfo)
• RecyclerView.ItemAnimator#animatePersistence(RecyclerView.ViewHolder, ItemHolderInfo, ItemHolderInfo)
• RecyclerView.ItemAnimator#animateAppearance(RecyclerView.ViewHolder, ItemHolderInfo, ItemHolderInfo)

dispatchMoveStarting

fun dispatchMoveStarting(item: RecyclerView.ViewHolder!): Unit

Method to be called by subclasses when a move animation is being started.

Parameters
item	RecyclerView.ViewHolder!: The item being moved

dispatchRemoveFinished

fun dispatchRemoveFinished(item: RecyclerView.ViewHolder!): Unit

Method to be called by subclasses when a remove animation is done.

Parameters
item	RecyclerView.ViewHolder!: The item which has been removed

See Also

• RecyclerView.ItemAnimator#animateDisappearance(RecyclerView.ViewHolder, ItemHolderInfo, * ItemHolderInfo)

dispatchRemoveStarting

fun dispatchRemoveStarting(item: RecyclerView.ViewHolder!): Unit

Method to be called by subclasses when a remove animation is being started.

Parameters
item	RecyclerView.ViewHolder!: The item being removed

getSupportsChangeAnimations

open fun getSupportsChangeAnimations(): Boolean

Returns whether this ItemAnimator supports animations of change events.

Return
Boolean	true if change animations are supported, false otherwise

onAddFinished

open fun onAddFinished(item: RecyclerView.ViewHolder!): Unit

Called when an add animation has ended on the given ViewHolder. The default implementation does nothing. Subclasses may wish to override this method to handle any ViewHolder-specific operations linked to animation lifecycles.

Parameters
item	RecyclerView.ViewHolder!: The ViewHolder being animated.

onAddStarting

open fun onAddStarting(item: RecyclerView.ViewHolder!): Unit

Called when an add animation is being started on the given ViewHolder. The default implementation does nothing. Subclasses may wish to override this method to handle any ViewHolder-specific operations linked to animation lifecycles.

Parameters
item	RecyclerView.ViewHolder!: The ViewHolder being animated.

onChangeFinished

open fun onChangeFinished(
    item: RecyclerView.ViewHolder!, 
    oldItem: Boolean
): Unit

Called when a change animation has ended on the given ViewHolder. The default implementation does nothing. Subclasses may wish to override this method to handle any ViewHolder-specific operations linked to animation lifecycles.

Parameters
item	RecyclerView.ViewHolder!: The ViewHolder being animated.
oldItem	Boolean: true if this is the old item that was changed, false if it is the new item that replaced the old item.

onChangeStarting

open fun onChangeStarting(
    item: RecyclerView.ViewHolder!, 
    oldItem: Boolean
): Unit

Called when a change animation is being started on the given ViewHolder. The default implementation does nothing. Subclasses may wish to override this method to handle any ViewHolder-specific operations linked to animation lifecycles.

Parameters
item	RecyclerView.ViewHolder!: The ViewHolder being animated.
oldItem	Boolean: true if this is the old item that was changed, false if it is the new item that replaced the old item.

onMoveFinished

open fun onMoveFinished(item: RecyclerView.ViewHolder!): Unit

Called when a move animation has ended on the given ViewHolder. The default implementation does nothing. Subclasses may wish to override this method to handle any ViewHolder-specific operations linked to animation lifecycles.

Parameters
item	RecyclerView.ViewHolder!: The ViewHolder being animated.

onMoveStarting

open fun onMoveStarting(item: RecyclerView.ViewHolder!): Unit

Called when a move animation is being started on the given ViewHolder. The default implementation does nothing. Subclasses may wish to override this method to handle any ViewHolder-specific operations linked to animation lifecycles.

Parameters
item	RecyclerView.ViewHolder!: The ViewHolder being animated.

onRemoveFinished

open fun onRemoveFinished(item: RecyclerView.ViewHolder!): Unit

Called when a remove animation has ended on the given ViewHolder. The default implementation does nothing. Subclasses may wish to override this method to handle any ViewHolder-specific operations linked to animation lifecycles.

Parameters
item	RecyclerView.ViewHolder!: The ViewHolder being animated.

onRemoveStarting

open fun onRemoveStarting(item: RecyclerView.ViewHolder!): Unit

Called when a remove animation is being started on the given ViewHolder. The default implementation does nothing. Subclasses may wish to override this method to handle any ViewHolder-specific operations linked to animation lifecycles.

Parameters
item	RecyclerView.ViewHolder!: The ViewHolder being animated.

setSupportsChangeAnimations

open fun setSupportsChangeAnimations(supportsChangeAnimations: Boolean): Unit

Sets whether this ItemAnimator supports animations of item change events. If you set this property to false, actions on the data set which change the contents of items will not be animated. What those animations do is left up to the discretion of the ItemAnimator subclass, in its animateChange(RecyclerView.ViewHolder, RecyclerView.ViewHolder, int, int, int, int) implementation. The value of this property is true by default.

Parameters
supportsChangeAnimations	Boolean: true if change animations are supported by this ItemAnimator, false otherwise. If the property is false, the ItemAnimator will not receive a call to animateChange(RecyclerView.ViewHolder, RecyclerView.ViewHolder, int, int, int, * int) when changes occur.

See Also

• RecyclerView.Adapter#notifyItemChanged(int)
• RecyclerView.Adapter#notifyItemRangeChanged(int, int)