recyclerview/androidx.recyclerview.widget/ItemTouchHelper

ItemTouchHelper

open class ItemTouchHelper : RecyclerView.ItemDecoration, RecyclerView.OnChildAttachStateChangeListener(source)

(SESL variant) This is a utility class to add swipe to dismiss and drag &drop support to RecyclerView.

It works with a RecyclerView and a Callback class, which configures what type of interactions are enabled and also receives events when user performs these actions.

Depending on which functionality you support, you should override onMove and / or onSwiped.

This class is designed to work with any LayoutManager but for certain situations, it can be optimized for your custom LayoutManager by extending methods in the ItemTouchHelper.Callback class or implementing ItemTouchHelper.ViewDropHandler interface in your LayoutManager.

By default, ItemTouchHelper moves the items' translateX/Y properties to reposition them. You can customize these behaviors by overriding onChildDraw or onChildDrawOver.

Most of the time you only need to override onChildDraw.

Constructors

ItemTouchHelper

constructor(@NonNull callback: ItemTouchHelper.Callback)

Creates an ItemTouchHelper that will work with the given Callback.

Types

abstract class Callback

This class is the contract between ItemTouchHelper and your application.

abstract class SimpleCallback : 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.

ViewDropHandler

interface ViewDropHandler

An interface which can be implemented by LayoutManager for better integration with ItemTouchHelper.

Properties

ACTION_STATE_DRAG

val ACTION_STATE_DRAG: Int = 2

A View is currently being dragged.

ACTION_STATE_IDLE

val ACTION_STATE_IDLE: Int = 0

ItemTouchHelper is in idle state.

ACTION_STATE_SWIPE

val ACTION_STATE_SWIPE: Int = 1

A View is currently being swiped.

ANIMATION_TYPE_DRAG

val ANIMATION_TYPE_DRAG: Int = 8

Animation type for views that were dragged and now will animate to their final position.

ANIMATION_TYPE_SWIPE_CANCEL

val ANIMATION_TYPE_SWIPE_CANCEL: Int = 4

Animation type for views which are not completely swiped thus will animate back to their original position.

ANIMATION_TYPE_SWIPE_SUCCESS

val ANIMATION_TYPE_SWIPE_SUCCESS: Int = 2

Animation type for views which are swiped successfully.

val DOWN: Int = 2

Down direction, used for swipe &drag control.

val END: Int = 32

Horizontal end direction.

val LEFT: Int = 4

Left direction, used for swipe &drag control.

val RIGHT: Int = 8

Right direction, used for swipe &drag control.

val START: Int = 16

Horizontal start direction.

val UP: Int = 1

Up direction, used for swipe &drag control.

Functions

attachToRecyclerView

open fun attachToRecyclerView(@Nullable recyclerView: RecyclerView)

Attaches the ItemTouchHelper to the provided RecyclerView.

open fun getItemOffsets(outRect: Rect, view: View, parent: RecyclerView, state: RecyclerView.State)

Retrieve any offsets for the given item.

onChildViewAttachedToWindow

open fun onChildViewAttachedToWindow(@NonNull view: View)

Called when a view is attached to the RecyclerView.

onChildViewDetachedFromWindow

open fun onChildViewDetachedFromWindow(@NonNull view: View)

Called when a view is detached from RecyclerView.

open fun onDraw(c: Canvas, parent: RecyclerView, state: RecyclerView.State)

Draw any appropriate decorations into the Canvas supplied to the RecyclerView.

open fun onDrawOver(@NonNull c: Canvas, @NonNull parent: RecyclerView, @NonNull state: RecyclerView.State)

Draw any appropriate decorations into the Canvas supplied to the RecyclerView.

seslIsPagingTouchSlopForStylusEnabled

open fun seslIsPagingTouchSlopForStylusEnabled(): Boolean

seslSetPagingTouchSlopForStylus

open fun seslSetPagingTouchSlopForStylus(enabled: Boolean)

setEndDraggingText

open fun setEndDraggingText(text: String)

setMoveDraggingText

open fun setMoveDraggingText(text: String)

setStartDraggingText

open fun setStartDraggingText(text: String)

open fun startDrag(@NonNull viewHolder: RecyclerView.ViewHolder)

Starts dragging the provided ViewHolder.

open fun startSwipe(@NonNull viewHolder: RecyclerView.ViewHolder)

Starts swiping the provided ViewHolder.