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ListUpdateCallback

interface ListUpdateCallback
androidx.recyclerview.widget.ListUpdateCallback

An interface that can receive Update operations that are applied to a list.

This class can be used together with DiffUtil to detect changes between two lists.

Summary

Public methods

abstract Unit
onChanged(position: Int, count: Int, @Nullable payload: Any?)

Called when count number of items are updated at the given position.

abstract Unit
onInserted(position: Int, count: Int)

Called when count number of items are inserted at the given position.

abstract Unit
onMoved(fromPosition: Int, toPosition: Int)

Called when an item changes its position in the list.

abstract Unit
onRemoved(position: Int, count: Int)

Called when count number of items are removed from the given position.

Public methods

onChanged

abstract fun onChanged(position: Int, count: Int, @Nullable payload: Any?): Unit

Called when count number of items are updated at the given position.

Parameters
position Int: The position of the item which has been updated.
count Int: The number of items which has changed.

onInserted

abstract fun onInserted(position: Int, count: Int): Unit

Called when count number of items are inserted at the given position.

Parameters
position Int: The position of the new item.
count Int: The number of items that have been added.

onMoved

abstract fun onMoved(fromPosition: Int, toPosition: Int): Unit

Called when an item changes its position in the list.

Parameters
fromPosition Int: The previous position of the item before the move.
toPosition Int: The new position of the item.

onRemoved

abstract fun onRemoved(position: Int, count: Int): Unit

Called when count number of items are removed from the given position.

Parameters
position Int: The position of the item which has been removed.
count Int: The number of items which have been removed.