FocusDelegate

Kotlin |Java

abstract class FocusDelegate<K : Any!>

kotlin.Any
↳	androidx.recyclerview.selection.FocusDelegate

Override methods in this class to provide application specific behaviors related to focusing item.

Summary

Public constructors
<init>() Override methods in this class to provide application specific behaviors related to focusing item.

Public methods
abstract Unit	clearFocus() If the environment supports focus and something is focused, unfocus it.
abstract Unit	focusItem(@NonNull item: ItemDetailsLookup.ItemDetails<K>) If environment supports focus, focus item.
abstract Int	getFocusedPosition() Returns the position of the currently focused item, or RecyclerView#NO_POSITION if nothing is focused.
abstract Boolean	hasFocusedItem()

Public constructors

<init>

FocusDelegate()

Override methods in this class to provide application specific behaviors related to focusing item.

Public methods

clearFocus

abstract fun clearFocus(): Unit

If the environment supports focus and something is focused, unfocus it.

focusItem

abstract fun focusItem(@NonNull item: ItemDetailsLookup.ItemDetails<K>): Unit

If environment supports focus, focus item.

getFocusedPosition

abstract fun getFocusedPosition(): Int

Returns the position of the currently focused item, or RecyclerView#NO_POSITION if nothing is focused.

You must implement this feature if you intend your app to work well with mouse and keyboard. Selection ranges are inferred from focused item when there is no explicit last-selected item.

You can manage and advance focus using keyboard arrows, reflecting this state visibly in the view item. Use can then press shift, then click another item with their mouse to select all items between the focused item and the clicked item.

Return
Int: the position of the currently focused item, or RecyclerView#NO_POSITION if none.

hasFocusedItem

abstract fun hasFocusedItem(): Boolean

Return
Boolean: true if there is a focused item.