Implement GestureDetector.OnDoubleTapListener properly on custom view

Question

I have a CustomAutoCompleteTextView and I want to be able to call showDropDown(); when the user double-tap on it.

As the title says implements GestureDetector.OnDoubleTapListener sounds like a good solution, but once added the mandatory methods to my custom view I have no idea on how to set the whole thing up

These are the methods to implement:

 @Override
    public boolean onSingleTapConfirmed(MotionEvent e) {
        return false;
    }

    @Override
    public boolean onDoubleTap(MotionEvent e) {
        return false;
    }

    @Override
    public boolean onDoubleTapEvent(MotionEvent e) {
        return false;
    }

I want to archive something like this:

@Override
        public boolean onDoubleTapEvent(MotionEvent e) {
            showDropDown();//AutoCompleteTextView's this line is enough but the event is never triggered
            return super.doYourThing();
        }

Answer 1

I've found a better way than implements GestureDetector.OnDoubleTapListener to archive this, notice that this solution is for implement double tap inside a custom view and all of its instances

boolean firstTouch = false;
    long time;
    @Override
    public boolean onTouchEvent(MotionEvent event) {
        if(event.getAction() == event.ACTION_DOWN){
            if(firstTouch && (System.currentTimeMillis() - time) <= 300) {
                firstTouch = false;
                showDropDown();//In my case I want to showDropDown() change this line for whatever you want to do
            } else {
                firstTouch = true;
                time = System.currentTimeMillis();
                return super.onTouchEvent(event);
                //return false;Use this if you dont want to call default onTouchEvent()
            }
        }
        return super.onTouchEvent(event);
         //return false;Use this if you dont want to call default onTouchEvent()
    }

Answer 2

1) create a new GestureDetector()

detector = new GestureDetector(this,new OnGestureListener() {

@Override
public boolean onDoubleTap(MotionEvent e) {
    showDropDown()
    return true;
}

2) Append your CustomAutoCompleteTextView with a OnTouchListener

txt.setOnTouchListener(new View.OnTouchListener() {

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

Answer 3

This is what worked well for me:

tapDetector = new GestureDetector(context, new GestureDetector.SimpleOnGestureListener());

tapDetector.setOnDoubleTapListener(new GestureDetector.OnDoubleTapListener() {
            @Override
            public boolean onSingleTapConfirmed(MotionEvent e){
              //Notified when a single-tap occurs.
              Log.w("Debug","Single tap event occurred in view with ID: "+ getId());
              return true;
            }
    
            @Override
            public boolean onDoubleTap(MotionEvent e) {
              Log.w("Debug","Double tap event occurred in view with ID: "+ getId());
              return true;
            }
    
            @Override
            public boolean onDoubleTapEvent(MotionEvent e)  {
              //Notified when an event within a double-tap gesture occurs, including the down, move, and up events.
              return true;
            }
          });

As mentioned in the previous solution:

txt.setOnTouchListener(new View.OnTouchListener() {

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        tapDetector.onTouchEvent(event);
        return false;
    }
});