Question

我有一个拖放代码。如果用户触摸该项，请OnTouchListener

代码开始：

View.OnTouchListener dragListener = new View.OnTouchListener() {
    @Override
    public boolean onTouch(View view, MotionEvent motionEvent) {
        // start move on a touch event
        if (motionEvent.getAction() == MotionEvent.ACTION_DOWN) {
            ClipData data = ClipData.newPlainText("", "");
            View.DragShadowBuilder shadowBuilder = new View.DragShadowBuilder(view);
            view.startDrag(data, shadowBuilder, view, 0);
            // API 24
            // view.startDragAndDrop(data, shadowBuilder, view, View.DRAG_FLAG_GLOBAL); // API 24
            view.setVisibility(View.VISIBLE);
            return true;
        }
        return false;
    }
};

但我的代码上会有OnLongClickListener。如果用户保留（长按）该项目，则显示屏上会显示一个Toast消息：

    homebutton.setOnLongClickListener(new OnLongClickListener() {
public boolean onLongClick(View arg0) {
    Toast.makeText(UserArea.this, "laaaange geklickt", Toast.LENGTH_SHORT).show();
    return true;  
}
});

但它不起作用： - （

Answer 1

从你的听众那里返回错误

View.OnTouchListener dragListener = new View.OnTouchListener() {
    @Override
    public boolean onTouch(View view, MotionEvent motionEvent) {
        //your logic 
        return false;
    }
};

否则您的活动将被视为已完成

Answer 2

编辑您的触摸事件并根据阈值确定TOuch或长按

private float mDownX;
private float mDownY;
private final float SCROLL_THRESHOLD = 10;
private boolean isOnClick;

@Override
public boolean onTouchEvent(MotionEvent ev) {
    switch (ev.getAction() & MotionEvent.ACTION_MASK) {
        case MotionEvent.ACTION_DOWN:
            mDownX = ev.getX();
            mDownY = ev.getY();
            isOnClick = true;
            break;
        case MotionEvent.ACTION_CANCEL:
        case MotionEvent.ACTION_UP:
            if (isOnClick) {
                Log.i(LOG_TAG, "onClick ");
                //TODO onClick code
            }
            break;
        case MotionEvent.ACTION_MOVE:
            if (isOnClick && (Math.abs(mDownX - ev.getX()) > SCROLL_THRESHOLD || Math.abs(mDownY - ev.getY()) > SCROLL_THRESHOLD)) {
                Log.i(LOG_TAG, "movement detected");
                isOnClick = false;
            }
            break;
        default:
            break;
    }
    return true;
}

OnLongClickListener不起作用

2 个答案: