continuous actions to be performed when I long tapped MGWT button until the touch end event fired

Question

I want to invoke a method continuously when I used MGWT button long tap handler, this should be done until I release the button. i.e; until the touch end event fired. For this I had written Timer inside the MGWT Button's long tap handler.I continuously calling the my task method inside the run method of the Timer. my code:

upButton.addLongTapHandler(new LongTapHandler() {

        @Override
        public void onLongTap(LongTapEvent event) {
             upBtnTimer = new Timer() {

                    @Override
                    public void run() {

                        if(getValue() >= maxValue){
                            Window.alert("max val reached");
                            upBtnTimer.cancel();
                        }else{
                            setValue(getValue() + RATE);
                        }

                    }
                };

            upBtnTimer.scheduleRepeating(100);
        }
    });

And I also wrote touch end handler to the upButton. this is:

 upButton.addTouchEndHandler(new TouchEndHandler() {

        @Override
        public void onTouchEnd(TouchEndEvent event) {
            if(upBtnTimer!=null){
            upBtnTimer.cancel();
            upBtnTimer = null;
            }
        }
    });

this is OK when I'm testing my mobile application on browser, but when I installed my application in iOS/Android device, this is not working. Only single tap event firing. If you are clear with my requirement please tell me if there is another approach to do this. Thanks in advance.