如何在recyclerview中增加向左向右滑动

Question

我正在尝试为我的RecolyerView添加滑动功能。我正在跟随这个链接添加刷卡。https://github.com/nikhilpanju/recyclerviewenhanced/blob/master/recyclerviewenhanced/src/main/java/com/nikhilpanju/recyclerviewenhanced/recyclertouchlistener.java

在这个链接中，我只能做从右到左的滑动。我要添加左到右滑动。我尝试在OnInterceptTouchEvent中添加功能。但我不能做从左到右的滑动。有没有人可以帮我添加左右滑动？

Answer 1

要在RecolyerView中实现此类行为，需要声明ItemTouchHelper，如下所示：

// The class to detect swipes and drags
private lateinit var itemTouchHelper: ItemTouchHelper

ItemTouchHelper类有一个ItemTouchHelper.SimpleCallback.OnChildDraw回调方法，您可以在该方法中检测用户是向右还是向左扫描了RecyclerView中的项。接下来，我们将实现这个回调，如下所示：

private fun setupRecyclerView() {
    val myRecyclerView = findViewById<RecyclerView>(R.id.myRecyclerView)
    val customAdapter = CustomAdapter()
    myRecyclerView.adapter = customAdapter

    val simpleCallback = object :
        ItemTouchHelper.SimpleCallback(
            0,
            ItemTouchHelper.LEFT or ItemTouchHelper.RIGHT
        ) {
        override fun onMove(
            recyclerView: RecyclerView,
            viewHolder: RecyclerView.ViewHolder,
            target: RecyclerView.ViewHolder
        ): Boolean = false

        override fun onChildDraw(
            c: Canvas,
            recyclerView: RecyclerView,
            viewHolder: RecyclerView.ViewHolder,
            dX: Float,
            dY: Float,
            actionState: Int,
            isCurrentlyActive: Boolean
        ) {

           // If you want to add a background, a text, an icon
          //  as the user swipes, this is where to start decorating
          //  I will link you to a library I created for that below

            super.onChildDraw(
                c,
                recyclerView,
                viewHolder,
                dX,
                dY,
                actionState,
                isCurrentlyActive
            )
        }

        override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {
            val position = viewHolder.adapterPosition
            when (direction) {
                ItemTouchHelper.LEFT -> {
                   // Do something when a user swept left
                }
                ItemTouchHelper.RIGHT -> {
                  // Do something when a user swept right
                }
            }
        }
    }
    itemTouchHelper = ItemTouchHelper(simpleCallback)
    itemTouchHelper.attachToRecyclerView(myRecyclerView)
}

现在将在您的RecolyerView中监听刷取行为。此外，如果你想要一个背景，图标或文本显示为你的应用程序的用户滑动，你可以使用这个很棒的库我创建的只是为了这个用途。如果您正在使用Gradle，您可以将其下载到您的项目中。下面是它的文档链接：https://github.com/kevingermainbusiness/itemdecorator