1+ package me.yifeiyuan.flap.ext
2+
3+ import android.graphics.Canvas
4+ import android.graphics.Color
5+ import android.graphics.drawable.ColorDrawable
6+ import android.graphics.drawable.Drawable
7+ import androidx.recyclerview.widget.*
8+
9+ /* *
10+ *
11+ * 封装处理 滑动删除 和 长按拖放排序 功能
12+ *
13+ * Created by 程序亦非猿 on 2022/8/17.
14+ *
15+ * @since 3.0.6
16+ */
17+ class SwipeDragHelper (private val callback : Callback ) : ItemTouchHelper.Callback() {
18+
19+ /* *
20+ * 拖动是否可用
21+ */
22+ private var isDragEnable = true
23+
24+ /* *
25+ * 滑动删除是否可用
26+ */
27+ private var isSwipeEnable = true
28+
29+ private var dragFlags = - 1
30+ private var swipeFlags = - 1
31+
32+ private var swipeThreshold = 0.5f
33+ private var dragThreshold = 0.5f
34+
35+ private var onMove: ((fromPosition: Int , toPosition: Int ) -> Unit )? = null
36+ private var onDismiss: ((position: Int ) -> Unit )? = null
37+
38+ private var swipeBackground: Drawable ? = null
39+
40+ private val itemTouchHelper: ItemTouchHelper = ItemTouchHelper (this )
41+
42+ override fun isLongPressDragEnabled (): Boolean {
43+ return isDragEnable
44+ }
45+
46+ override fun isItemViewSwipeEnabled (): Boolean {
47+ return isSwipeEnable
48+ }
49+
50+ override fun getMovementFlags (recyclerView : RecyclerView , viewHolder : RecyclerView .ViewHolder ): Int {
51+ val finalDragFlags = if (dragFlags != - 1 ) dragFlags else genDefaultDragFlags(recyclerView, viewHolder)
52+ val finalSwipeFlags = if (swipeFlags != - 1 ) swipeFlags else genDefaultSwipeFlags(recyclerView, viewHolder)
53+ return makeMovementFlags(finalDragFlags, finalSwipeFlags)
54+ }
55+
56+ private fun genDefaultDragFlags (recyclerView : RecyclerView , viewHolder : RecyclerView .ViewHolder ): Int {
57+ return when (recyclerView.layoutManager) {
58+ is StaggeredGridLayoutManager -> {
59+ ItemTouchHelper .UP or ItemTouchHelper .DOWN or ItemTouchHelper .LEFT or ItemTouchHelper .RIGHT
60+ }
61+ is GridLayoutManager -> {
62+ ItemTouchHelper .UP or ItemTouchHelper .DOWN or ItemTouchHelper .LEFT or ItemTouchHelper .RIGHT
63+ }
64+ is LinearLayoutManager -> {
65+ ItemTouchHelper .UP or ItemTouchHelper .DOWN
66+ }
67+ else -> {
68+ ItemTouchHelper .UP or ItemTouchHelper .DOWN
69+ }
70+ }
71+ }
72+
73+ private fun genDefaultSwipeFlags (recyclerView : RecyclerView , viewHolder : RecyclerView .ViewHolder ): Int {
74+ return when (recyclerView.layoutManager) {
75+ is StaggeredGridLayoutManager -> {
76+ ItemTouchHelper .UP or ItemTouchHelper .DOWN or ItemTouchHelper .LEFT or ItemTouchHelper .RIGHT
77+ }
78+ is GridLayoutManager -> {
79+ ItemTouchHelper .UP or ItemTouchHelper .DOWN or ItemTouchHelper .LEFT or ItemTouchHelper .RIGHT
80+ }
81+ is LinearLayoutManager -> {
82+ ItemTouchHelper .START or ItemTouchHelper .END
83+ }
84+ else -> {
85+ ItemTouchHelper .START or ItemTouchHelper .END
86+ }
87+ }
88+ }
89+
90+ override fun onMove (recyclerView : RecyclerView , viewHolder : RecyclerView .ViewHolder , target : RecyclerView .ViewHolder ): Boolean {
91+ if (viewHolder.itemViewType == target.itemViewType) {
92+ onMove?.invoke(viewHolder.adapterPosition, target.adapterPosition)
93+ return true
94+ }
95+ return false
96+ }
97+
98+ fun onItemMove (block : (fromPosition: Int , toPosition: Int ) -> Unit ): SwipeDragHelper {
99+ onMove = block
100+ return this
101+ }
102+
103+ // Item 被滑动删除了调用
104+ override fun onSwiped (viewHolder : RecyclerView .ViewHolder , direction : Int ) {
105+ onDismiss?.invoke(viewHolder.adapterPosition)
106+ callback.onItemDismiss(viewHolder.adapterPosition)
107+ }
108+
109+ fun onItemDismiss (block : (position: Int ) -> Unit ): SwipeDragHelper {
110+ onDismiss = block
111+ return this
112+ }
113+
114+ fun attachToRecyclerView (recyclerView : RecyclerView ): SwipeDragHelper {
115+ itemTouchHelper.attachToRecyclerView(recyclerView)
116+ return this
117+ }
118+
119+ override fun onSelectedChanged (viewHolder : RecyclerView .ViewHolder ? , actionState : Int ) {
120+ super .onSelectedChanged(viewHolder, actionState)
121+ }
122+
123+ override fun getSwipeThreshold (viewHolder : RecyclerView .ViewHolder ): Float {
124+ return swipeThreshold
125+ }
126+
127+ override fun getMoveThreshold (viewHolder : RecyclerView .ViewHolder ): Float {
128+ return dragThreshold
129+ }
130+
131+ /* *
132+ * onMove return true 后会调用
133+ */
134+ override fun onMoved (recyclerView : RecyclerView , viewHolder : RecyclerView .ViewHolder , fromPos : Int , target : RecyclerView .ViewHolder , toPos : Int , x : Int , y : Int ) {
135+ super .onMoved(recyclerView, viewHolder, fromPos, target, toPos, x, y)
136+ callback.onItemMoved(fromPos, toPos)
137+ }
138+
139+ /* *
140+ * 当用户交互完成后调用，此时动画也结束了，例如滑动删除后、拖放完毕
141+ * 在 onViewDetachedFromWindow 之后
142+ */
143+ override fun clearView (recyclerView : RecyclerView , viewHolder : RecyclerView .ViewHolder ) {
144+ super .clearView(recyclerView, viewHolder)
145+ }
146+
147+ override fun onChildDraw (c : Canvas , recyclerView : RecyclerView , viewHolder : RecyclerView .ViewHolder , dX : Float , dY : Float , actionState : Int , isCurrentlyActive : Boolean ) {
148+ super .onChildDraw(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive)
149+ if (actionState == ItemTouchHelper .ACTION_STATE_SWIPE ) {
150+ // 滑动的时候可以绘制背景
151+ swipeBackground?.let {
152+ val itemView = viewHolder.itemView
153+ if (dX > 0 ) {
154+ it.setBounds(itemView.left, itemView.top, itemView.left + dX.toInt(), itemView.bottom)
155+ it.draw(c)
156+ } else {
157+ it.setBounds(itemView.right + dX.toInt(), itemView.top, itemView.right, itemView.bottom)
158+ it.draw(c)
159+ }
160+ }
161+ } else if (actionState == ItemTouchHelper .ACTION_STATE_DRAG ) {
162+ // 拖动
163+ }
164+ }
165+
166+ override fun onChildDrawOver (c : Canvas , recyclerView : RecyclerView , viewHolder : RecyclerView .ViewHolder ? , dX : Float , dY : Float , actionState : Int , isCurrentlyActive : Boolean ) {
167+ super .onChildDrawOver(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive)
168+ }
169+
170+ /* *
171+ * 拖动是否可用
172+ */
173+ fun withDragEnable (enable : Boolean ): SwipeDragHelper {
174+ isDragEnable = enable
175+ return this
176+ }
177+
178+ /* *
179+ * 滑动删除是否可用
180+ */
181+ fun withSwipeEnable (enable : Boolean ): SwipeDragHelper {
182+ isSwipeEnable = enable
183+ return this
184+ }
185+
186+ fun withDragFlags (dragFlags : Int ): SwipeDragHelper {
187+ this .dragFlags = dragFlags
188+ return this
189+ }
190+
191+ fun withSwipeFlags (swipeFlags : Int ): SwipeDragHelper {
192+ this .swipeFlags = swipeFlags
193+ return this
194+ }
195+
196+ fun withSwipeThreshold (swipeThreshold : Float ): SwipeDragHelper {
197+ this .swipeThreshold = swipeThreshold
198+ return this
199+ }
200+
201+ fun withDragThreshold (dragThreshold : Float ): SwipeDragHelper {
202+ this .dragThreshold = dragThreshold
203+ return this
204+ }
205+
206+ fun withSwipeBackground (swipeBackground : Drawable ): SwipeDragHelper {
207+ this .swipeBackground = swipeBackground
208+ return this
209+ }
210+
211+ interface Callback {
212+ fun onItemDismiss (position : Int )
213+ fun onItemMoved (fromPosition : Int , toPosition : Int )
214+ }
215+ }
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