universum.studios.android.recycler.helper

Interface ItemDragHelper.DragAdapter

Enclosing class:

ItemDragHelper

public static interface ItemDragHelper.DragAdapter

Required interface for adapters which want to support drag feature for theirs ViewHolders.

Since:

1.0

Author:

Martin Albedinsky

Method Summary

Modifier and Type	Method and Description
boolean	canDropItemOver(int currentPosition, int targetPosition) Called by the drag helper to check if item associated with the currentPosition can be dropped at the specified targetPosition.
int	getItemDragFlags(int position) Called by the drag helper to obtain drag movement flags for an item at the specified position.
void	onItemDragFinished(int fromPosition, int toPosition) Called by the drag helper whenever drag gesture for item associated with the specified fromPosition has finished.
void	onItemDragStarted(int position) Called by the drag helper whenever drag gesture for item associated with the specified position has started.
boolean	onMoveItem(int currentPosition, int targetPosition) Called by the drag helper to inform this adapter that it should move its item in its data set from the specified currentPosition to the specified targetPosition.

Method Detail

getItemDragFlags

int getItemDragFlags(int position)

Called by the drag helper to obtain drag movement flags for an item at the specified position.

Parameters:

position - Position of the item for which to obtain its drag flags.

Returns:

Movement flags determining in which direction can be the item dragged.

See Also:

ItemDragHelper.makeDragFlags(int)

onItemDragStarted

void onItemDragStarted(int position)

Called by the drag helper whenever drag gesture for item associated with the specified position has started.

Parameters:

position - Position of the view holder of which view started to be dragged by the user.

See Also:

onItemDragFinished(int, int), onMoveItem(int, int)

onMoveItem

boolean onMoveItem(int currentPosition,
                   int targetPosition)

Called by the drag helper to inform this adapter that it should move its item in its data set from the specified currentPosition to the specified targetPosition.

Parameters:

currentPosition - The position from which should be the item moved in this adapter's data set.

targetPosition - The position to which should be the item moved in this adapter's data set.

Returns:

True if item has been moved form the current position to the target one, false otherwise.

canDropItemOver

boolean canDropItemOver(int currentPosition,
                        int targetPosition)

Called by the drag helper to check if item associated with the currentPosition can be dropped at the specified targetPosition.

If this method returns true, this adapter receives onItemDragFinished(int, int) callback in a near feature.

Parameters:

currentPosition - Current position of the associated view holder.

targetPosition - Target position at which could be the associated view holder dropped.

Returns:

True if the holder can be dropped at the target position, false otherwise.

See Also:

onItemDragFinished(int, int)

onItemDragFinished

void onItemDragFinished(int fromPosition,
                        int toPosition)

Called by the drag helper whenever drag gesture for item associated with the specified fromPosition has finished.

Parameters:

fromPosition - The position from which has been the associated view holder started to be dragged.

toPosition - The position at which has been the associated view holder dropped.

See Also:

canDropItemOver(int, int), onItemDragStarted(int)