carbon.recycler

Class ItemTouchHelper.SimpleCallback

java.lang.Object

carbon.recycler.ItemTouchHelper.Callback

carbon.recycler.ItemTouchHelper.SimpleCallback

Enclosing class:

ItemTouchHelper

public abstract static class ItemTouchHelper.SimpleCallback
extends ItemTouchHelper.Callback

A simple wrapper to the default Callback which you can construct with drag and swipe directions and this class will handle the flag callbacks. You should still override onMove or onSwiped depending on your use case.

 ItemTouchHelper mIth = new ItemTouchHelper(
     new ItemTouchHelper.SimpleCallback(ItemTouchHelper.UP | ItemTouchHelper.DOWN,
         ItemTouchHelper.LEFT) {
         public abstract boolean onMove(RecyclerView recyclerView,
             RowViewHolder viewHolder, RowViewHolder target) {
             final int fromPos = viewHolder.getAdapterPosition();
             final int toPos = viewHolder.getAdapterPosition();
             // move item in `fromPos` to `toPos` in adapter.
             return true;// true if moved, false otherwise
         }
         public void onSwiped(RowViewHolder viewHolder, int direction) {
             // remove from adapter
         }
 });
 

Field Summary

Fields inherited from class carbon.recycler.ItemTouchHelper.Callback

DEFAULT_DRAG_ANIMATION_DURATION, DEFAULT_SWIPE_ANIMATION_DURATION

Constructor Summary

Constructors

Constructor and Description
SimpleCallback(int dragDirs, int swipeDirs) Creates a Callback for the given drag and swipe allowance.

Method Summary

Modifier and Type	Method and Description
int	getDragDirs(android.support.v7.widget.RecyclerView recyclerView, android.support.v7.widget.RecyclerView.ViewHolder viewHolder) Returns the drag directions for the provided RowViewHolder.
int	getMovementFlags(android.support.v7.widget.RecyclerView recyclerView, android.support.v7.widget.RecyclerView.ViewHolder viewHolder) Should return a composite flag which defines the enabled move directions in each state (idle, swiping, dragging).
int	getSwipeDirs(android.support.v7.widget.RecyclerView recyclerView, android.support.v7.widget.RecyclerView.ViewHolder viewHolder) Returns the swipe directions for the provided RowViewHolder.
void	setDefaultDragDirs(int defaultDragDirs) Updates the default drag directions.
void	setDefaultSwipeDirs(int defaultSwipeDirs) Updates the default swipe directions.

Methods inherited from class carbon.recycler.ItemTouchHelper.Callback

canDropOver, chooseDropTarget, clearView, convertToAbsoluteDirection, convertToRelativeDirection, getAnimationDuration, getBoundingBoxMargin, getDefaultUIUtil, getMoveThreshold, getSwipeEscapeVelocity, getSwipeThreshold, getSwipeVelocityThreshold, interpolateOutOfBoundsScroll, isItemViewSwipeEnabled, isLongPressDragEnabled, makeFlag, makeMovementFlags, onChildDraw, onChildDrawOver, onMove, onMoved, onSelectedChanged, onSwiped

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SimpleCallback

public SimpleCallback(int dragDirs,
                      int swipeDirs)

Creates a Callback for the given drag and swipe allowance. These values serve as defaults and if you want to customize behavior per RowViewHolder, you can override #getSwipeDirs(RecyclerView, ViewHolder) and / or #getDragDirs(RecyclerView, ViewHolder).

Parameters:

dragDirs - Binary OR of direction flags in which the Views can be dragged. Must be composed of ItemTouchHelper.LEFT, ItemTouchHelper.RIGHT, ItemTouchHelper.START, ItemTouchHelper.END, ItemTouchHelper.UP and ItemTouchHelper.DOWN.

swipeDirs - Binary OR of direction flags in which the Views can be swiped. Must be composed of ItemTouchHelper.LEFT, ItemTouchHelper.RIGHT, ItemTouchHelper.START, ItemTouchHelper.END, ItemTouchHelper.UP and ItemTouchHelper.DOWN.

Method Detail

setDefaultSwipeDirs

public void setDefaultSwipeDirs(int defaultSwipeDirs)

Updates the default swipe directions. For example, you can use this method to toggle certain directions depending on your use case.

Parameters:

defaultSwipeDirs - Binary OR of directions in which the ViewHolders can be swiped.

setDefaultDragDirs

public void setDefaultDragDirs(int defaultDragDirs)

Updates the default drag directions. For example, you can use this method to toggle certain directions depending on your use case.

Parameters:

defaultDragDirs - Binary OR of directions in which the ViewHolders can be dragged.

getSwipeDirs

public int getSwipeDirs(android.support.v7.widget.RecyclerView recyclerView,
                        android.support.v7.widget.RecyclerView.ViewHolder viewHolder)

Returns the swipe directions for the provided RowViewHolder. Default implementation returns the swipe directions that was set via constructor or setDefaultSwipeDirs(int).

Parameters:

recyclerView - The RecyclerView to which the ItemTouchHelper is attached to.

viewHolder - The RecyclerView for which the swipe drection is queried.

Returns:

A binary OR of direction flags.

getDragDirs

public int getDragDirs(android.support.v7.widget.RecyclerView recyclerView,
                       android.support.v7.widget.RecyclerView.ViewHolder viewHolder)

Returns the drag directions for the provided RowViewHolder. Default implementation returns the drag directions that was set via constructor or setDefaultDragDirs(int).

Parameters:

recyclerView - The RecyclerView to which the ItemTouchHelper is attached to.

viewHolder - The RecyclerView for which the swipe drection is queried.

Returns:

A binary OR of direction flags.

getMovementFlags

public int getMovementFlags(android.support.v7.widget.RecyclerView recyclerView,
                            android.support.v7.widget.RecyclerView.ViewHolder viewHolder)

Description copied from class: ItemTouchHelper.Callback

Should return a composite flag which defines the enabled move directions in each state (idle, swiping, dragging).

Instead of composing this flag manually, you can use ItemTouchHelper.Callback.makeMovementFlags(int, int) or ItemTouchHelper.Callback.makeFlag(int, int).

This flag is composed of 3 sets of 8 bits, where first 8 bits are for IDLE state, next 8 bits are for SWIPE state and third 8 bits are for DRAG state. Each 8 bit sections can be constructed by simply OR'ing direction flags defined in ItemTouchHelper.

For example, if you want it to allow swiping LEFT and RIGHT but only allow starting to swipe by swiping RIGHT, you can return:

      makeFlag(ACTION_STATE_IDLE, RIGHT) | makeFlag(ACTION_STATE_SWIPE, LEFT | RIGHT);
 

This means, allow right movement while IDLE and allow right and left movement while swiping.

Specified by:

getMovementFlags in class ItemTouchHelper.Callback

Parameters:

recyclerView - The RecyclerView to which ItemTouchHelper is attached.

viewHolder - The RowViewHolder for which the movement information is necessary.

Returns:

flags specifying which movements are allowed on this RowViewHolder.

See Also:

ItemTouchHelper.Callback.makeMovementFlags(int, int), ItemTouchHelper.Callback.makeFlag(int, int)