Recyclerview 拖放触摸

Question

我已经使用 ItemTouchHelper 在 recyclerview 中实现了拖放功能。它工作正常。但它只适用于长按。我需要用 onTouch

来完成

ItemTouchHelper.Callback itemTouchHelperCallback = new ItemTouchHelper.Callback() {
    public boolean onMove(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, RecyclerView.ViewHolder target) {
        Collections.swap(strings, viewHolder.getAdapterPosition(), target.getAdapterPosition());
        adapter.notifyItemMoved(viewHolder.getAdapterPosition(), target.getAdapterPosition());
        return true;
    }

    @Override
    public void onSwiped(RecyclerView.ViewHolder viewHolder, int direction) {
        //TODO
    }

   //defines the enabled move directions in each state (idle, swiping, dragging).
     @Override
     public int getMovementFlags(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder) {
         return makeFlag(ItemTouchHelper.ACTION_STATE_DRAG,
             ItemTouchHelper.DOWN | ItemTouchHelper.UP | ItemTouchHelper.START | ItemTouchHelper.END);
         }
    };

这是我使用的代码。请帮帮我！！！

Answer 1

覆盖 ItemTouchHelper 的 isLongPressDragEnabled 和 return false

https://developer.android.com/reference/android/support/v7/widget/helper/ItemTouchHelper.Callback#isLongPressDragEnabled()

override fun isLongPressDragEnabled(): Boolean = false

向 ViewHolder 的实现添加一个回调并使用它

buttonToDrag.setOnTouchListener { v, event ->
    listener.onTouch(this, event)
    false
}

在activity或片段中，使用startDrag

private lateinit var itemTouchHelper: ItemTouchHelper

override fun onTouch(viewHolder: RecyclerView.ViewHolder, event: MotionEvent) {
    if (event.actionMasked == MotionEvent.ACTION_DOWN) {
        itemTouchHelper.startDrag(viewHolder)
    }
}

我在 https://developer.android.com/reference/android/support/v7/widget/helper/ItemTouchHelper#startdrag

的文档中找到了实现

我亲自尝试过，效果非常好。

Answer 2

您可以在 onBindViewHolder 中使用以下代码开始触摸拖动

holder.layout.setOnTouchListener(new View.OnTouchListener() {
    @Override
    public boolean onTouch(View view, MotionEvent event) {

        ClipData data = ClipData.newPlainText("", "");
        View.DragShadowBuilder shadowBuilder = new View.DragShadowBuilder(view);
        view.startDrag(data, shadowBuilder, view, 0);
        view.setVisibility(View.INVISIBLE);

        return false;
    }
});

布局是指您的项目布局。在您可以将 DragListener 用于所有其他事件之后，例如

DragEvent.ACTION_DRAG_STARTED
DragEvent.ACTION_DRAG_ENTERED
DragEvent.ACTION_DRAG_EXITED
DragEvent.ACTION_DROP
DragEvent.ACTION_DRAG_ENDED

Recyclerview 拖放触摸

Recyclerview Drag and Drop ontouch

android

android-recyclerview

itemtouchhelper