SelectionPredicate
abstract class SelectionPredicate<K : Any!>
| kotlin.Any | |
| ↳ | androidx.recyclerview.selection.SelectionTracker.SelectionPredicate |
Implement SelectionPredicate to control when items can be selected or unselected. See Builder#withSelectionPredicate(SelectionPredicate).
Summary
| Public constructors | |
|---|---|
<init>()Implement SelectionPredicate to control when items can be selected or unselected. |
|
| Public methods | |
|---|---|
| abstract Boolean |
Permits restriction to single selection mode. |
| abstract Boolean |
canSetStateAtPosition(position: Int, nextState: Boolean)Validates a change to selection for a specific position. |
| abstract Boolean |
canSetStateForKey(@NonNull key: K, nextState: Boolean)Validates a change to selection for a specific key. |
Public constructors
<init>
SelectionPredicate()
Implement SelectionPredicate to control when items can be selected or unselected. See Builder#withSelectionPredicate(SelectionPredicate).
Public methods
canSelectMultiple
abstract fun canSelectMultiple(): Boolean
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).
| Return | |
|---|---|
| Boolean: true if more than a single item can be selected. |
canSetStateAtPosition
abstract fun canSetStateAtPosition(position: Int, nextState: Boolean): Boolean
Validates a change to selection for a specific position. If necessary use ItemKeyProvider to identy associated key.
| Parameters | |
|---|---|
position |
Int: the item position |
nextState |
Int: the next potential selected/unselected state |
| Return | |
|---|---|
Boolean: true if the item at id can be set to nextState. |