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How to catch double tap events in Android using OnTouchListener

I am trying to catch double-tap events using OnTouchListener. I figure I would set a long for motionEvent.ACTION_DOWN, and a different long for a second motionEvent.ACTION_DOWN and measure the time between the two of them and then do something with it. However, I am having a hard time figuring out exactly how to approach this. I am using switch cases to pick up multitouch events, so I'd rather not try and retool this all to implement GestureDetector (and unfortunately it is impossible to implement both ontouchlistener and Gesturedetector simultaneously). Any ideas would help greatly:

i.setOnTouchListener(new OnTouchListener() {

        public boolean onTouch(View v, MotionEvent event) {


                  ImageView i = (ImageView) v;

                  switch (event.getAction() & MotionEvent.ACTION_MASK) {


                  case MotionEvent.ACTION_DOWN:
                      long firstTouch = System.currentTimeMillis();
                     ///how to grab the second action_down????

                     break;
like image 837
benbeel Avatar asked Sep 06 '11 03:09

benbeel


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1 Answers

In your class definition:

public class main_activity extends Activity
{
    //variable for counting two successive up-down events
   int clickCount = 0;
    //variable for storing the time of first click
   long startTime;
    //variable for calculating the total time
   long duration;
    //constant for defining the time duration between the click that can be considered as double-tap
   static final int MAX_DURATION = 500;
}

Then in your class body:

OnTouchListener MyOnTouchListener = new OnTouchListener()
{
    @Override
    public boolean onTouch (View v, MotionEvent event)
    {
        switch(event.getAction() & MotionEvent.ACTION_MASK)
        {
        case MotionEvent.ACTION_DOWN:
            startTime = System.currentTimeMillis();
            clickCount++;
            break;
        case MotionEvent.ACTION_UP:
            long time = System.currentTimeMillis() - startTime;
            duration=  duration + time;
            if(clickCount == 2)
            {
                if(duration<= MAX_DURATION)
                {
                    Toast.makeText(captureActivity.this, "double tap",Toast.LENGTH_LONG).show();
                }
                clickCount = 0;
                duration = 0;
                break;             
            }
        }
    return true;    
    }
}

This was adapted from an answer in: DoubleTap in android by https://stackoverflow.com/users/1395802/karn

like image 69
birdman Avatar answered Oct 21 '22 20:10

birdman