listener for pressing and releasing a button

You can use a onTouchListener:

view.setOnTouchListener(new View.OnTouchListener() {        
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        switch(event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                // PRESSED
                return true; // if you want to handle the touch event
            case MotionEvent.ACTION_UP:
                // RELEASED
                return true; // if you want to handle the touch event
        }
        return false;
    }
});