SelectionTracker.SelectionPredicate
public
static
abstract
class
SelectionTracker.SelectionPredicate
extends Object
java.lang.Object | |
↳ | androidx.recyclerview.selection.SelectionTracker.SelectionPredicate<K> |
Implement SelectionPredicate to control when items can be selected or unselected.
See SelectionTracker.Builder.withSelectionPredicate(SelectionPredicate)
.
Summary
Public constructors | |
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SelectionPredicate()
|
Public methods | |
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abstract
boolean
|
canSelectMultiple()
Permits restriction to single selection mode. |
abstract
boolean
|
canSetStateAtPosition(int position, boolean nextState)
Validates a change to selection for a specific position. |
abstract
boolean
|
canSetStateForKey(K key, boolean nextState)
Validates a change to selection for a specific key. |
Inherited methods | |
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Public constructors
SelectionPredicate
public SelectionPredicate ()
Public methods
canSelectMultiple
public abstract boolean canSelectMultiple ()
Permits restriction to single selection mode. Single selection mode has unique behaviors in that it'll deselect an item already selected in order to select the new item.
In order to limit the number of items that can be selected,
use canSetStateForKey(Object, boolean)
and
canSetStateAtPosition(int, boolean)
.
Returns | |
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boolean |
true if more than a single item can be selected. |
canSetStateAtPosition
public abstract boolean canSetStateAtPosition (int position, boolean nextState)
Validates a change to selection for a specific position. If necessary
use ItemKeyProvider
to identy associated key.
Parameters | |
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position |
int : the item position |
nextState |
boolean : the next potential selected/unselected state |
Returns | |
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boolean |
true if the item at id can be set to nextState .
|
canSetStateForKey
public abstract boolean canSetStateForKey (K key, boolean nextState)
Validates a change to selection for a specific key.
Parameters | |
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key |
K : the item key |
nextState |
boolean : the next potential selected/unselected state |
Returns | |
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boolean |
true if the item at id can be set to nextState .
|