button.java

button.setOnTouchListener(new OnTouchListener() {
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        if(event.getAction() == MotionEvent.ACTION_DOWN) {
            // the button is down monitor time to see how long it is down or anything you want
        } else if (event.getAction() == MotionEvent.ACTION_UP) {
            // the button is up reset your timer
        }
    }
};