OnGestureListener onDown method never gets called

问题

My onScroll and areonTouchEvent getting called, but not the onDown method. In fact, when I log the distaceX in onDown I get several of them logged out, and the first is always relative to the spot where I ended the last scroll.

 @Override 
 public boolean onTouchEvent(MotionEvent me){ 
   this.detector.onTouchEvent(me);

  return super.onTouchEvent(me); 
 }

 @Override
 public boolean onDown(MotionEvent e) {
       Log.d("---onDown---",".");
   return false;

 }

 @Override
 public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,
   float distanceY) {
  Log.d("---onScroll---", "" + distanceX);
  return false;
 }

Any ideas why onDown would not be called?

EDIT:

I changed my onTouchEvent to the following block, and only the ACTION_MOVE gets logged.

 float gestureDistance = 0;
 @Override 
 public boolean onTouchEvent(MotionEvent me){ 
     switch (me.getAction() & MotionEvent.ACTION_MASK) {
        case MotionEvent.ACTION_DOWN:               
            Log.d("actionDown", "gestureDistance:" + gestureDistance);
            break;
        case MotionEvent.ACTION_UP:
            Log.d("actionUp", "gestureDistance:" + gestureDistance);
            break;
        case MotionEvent.ACTION_MOVE:
            Log.d("actionMove", "gestureDistance:" + gestureDistance);
            break;
        default:
            Log.d("action default", "default");
            break;
    }

EDIT: I think the problem is that my view is a WebView. Can I keep the webview from stealing my events?

回答1:

Why don't you do something like:

@Override
public boolean onTouchEvent(MotionEvent event) {        

    switch (event.getAction() & MotionEvent.ACTION_MASK) {
        case MotionEvent.ACTION_DOWN:               
            //Do something on action down.
        case MotionEvent.ACTION_UP:
            //Do something on action up.
            break;
        case MotionEvent.ACTION_MOVE:
            //Do something when moving.
            break;
    }   

    return true;
}

Hope this helps.

回答2:

Adding this to my onCreate fixed the problem.

    webView.setOnTouchListener(new View.OnTouchListener() {

        public boolean onTouch(View v, MotionEvent event) {
           detector.onTouchEvent(event);
            return true;
        }
    });

来源：https://stackoverflow.com/questions/11730425/ongesturelistener-ondown-method-never-gets-called

标签

android

gesture