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androidimageviewxamarin.androidgesture

GenericMotion - Action Down not firing


I want to trace the whole movement of a finger that started by touching my ImageView. I found that GenericMotion event should be the correct one to use.

What am I supposed to do (or to avoid) to get Actions Down, Move and Up in GenericMotion event? I get only HoverEnter, HoverMove and HoverExit actions, even if I start with touching the center of my ImageView.

Android: OnTouch, MotionEvent.ACTION_MOVE is not recognized?

Here I learned that without handling Down action I can't get the remaining actions, but I don't get the Down action!

private void OnPlayerInfoRatingGenericMotion(object sender, View.GenericMotionEventArgs e)
{
    //goes here only with hover actions
    if (e.Event.Action==MotionEventActions.Down)
    {
        //never goes here
    }
    if (e.Event.Action==MotionEventActions.Move)
    {
        //never goes here
    }
}

What am I doing wrong?


Solution

  • GenericMotion can not detect the gesture of your finger. I think it is only used to report for movement event. You can refer to the document here.

    For example , You can move your imageview from top to bottom then the GenericMotion can detect the "move" action.

    If you want to detect your finger event I think you can achieve OnTouchListener.

    For example:

    imgview.SetOnTouchListener(new MyTouchListener());

    achieve MyTouchListener:

    public class MyTouchListener: Java.Lang.Object, View.IOnTouchListener
    {
        public bool OnTouch(View v, MotionEvent e)
        {
            throw new NotImplementedException();
        }
    
        public bool OnTouchEvent(View v, MotionEvent e)
        {
            if (e.Action == MotionEventActions.Down)
            {
                Log.Debug("Mike", "Down");
                Console.WriteLine("Down");
                return true;
            }
            if (e.Action == MotionEventActions.Up)
            {
                Log.Debug("Mike", "Up");
                Console.WriteLine("Up");
                return true;
            }
            if (e.Action == MotionEventActions.Move)
            {
                Log.Debug("Mike", "Move");
                Console.WriteLine("Move");
                return true;
            }
    
            return false;
        }
    }
    

    Also you can achieve IOnGestureListener to detect your gesture.