SelectionTracker.SelectionPredicate
public abstract class SelectionTracker.SelectionPredicate<K>
Implement SelectionPredicate to control when items can be selected or unselected. See withSelectionPredicate.
| Parameters | |
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<K> |
Selection key type. @see |
Summary
Public constructors |
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Public methods |
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abstract boolean |
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(@NonNull K key, boolean nextState)Validates a change to selection for a specific key. |
Public constructors
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 and canSetStateAtPosition.
| Returns | |
|---|---|
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 | |
|---|---|
int position |
the item position |
boolean nextState |
the next potential selected/unselected state |
| Returns | |
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boolean |
true if the item at |
canSetStateForKey
public abstract boolean canSetStateForKey(@NonNull K key, boolean nextState)
Validates a change to selection for a specific key.
| Parameters | |
|---|---|
@NonNull K key |
the item key |
boolean nextState |
the next potential selected/unselected state |
| Returns | |
|---|---|
boolean |
true if the item at |