How to implement double tap for Android live wallpapers?

Question

I want to implement a double tap event for a Android live wallpaper. Sadly, I couldn´t find any specific code how to do that.

At the moment I´ve found a workarround using the onTouchEvent-method of the Engine-class:

public void onTouchEvent(MotionEvent event) {
  long time = android.os.SystemClock.currentThreadTimeMillis();

  if(((time - mLastTouchTime) < 500) && ((time - mLastTouchTime) > 100))
  {
    if(!mIsPlayed && mSound)
      {
        mIsPlayed = true;
        int sound = R.raw.hell;
        if(mTheme.equals("rose"))
          sound = R.raw.rose;
        if(mTheme.equals("greed"))
          sound = R.raw.greed;

        MediaPlayer mp = MediaPlayer.create(getBaseContext(), sound);   
          mp.start();
          mp.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
      @Override
      public void onCompletion(MediaPlayer mp) {
        // TODO Auto-generated method stub
        mp.release();
        mIsPlayed = false;
      }
    });
      }
  }

  mLastTouchTime = time;
  super.onTouchEvent(event);
}

Well, that´s not an elegant solution. I know there are wallpapers which implemented the double tap. But I have no idea, how to do it on my own.

So a "tap" in the right direction would be nice. If nescessary, I will accept a "double tap". :D

Greetings, Robert

Answer 1

Use http://developer.android.com/reference/android/view/GestureDetector.html

for example:

public class AndroidTestActivity extends Activity {

    private GestureDetector gestureDetector;

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        return gestureDetector.onTouchEvent(event);
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        gestureDetector = new GestureDetector(new GestureDetector.SimpleOnGestureListener(){
            @Override
            public boolean onDoubleTap(MotionEvent e) {
                Log.e("onDoubleTap", e.toString());
                //handle double tap
                return true;
            }
        });
    }
}