private async Task InitializeTouch(CoreDispatcher dispatcher)
        {
            var touchScreen = await TouchDevice.Get();

            var touchProcessor = new TouchProcessor(touchScreen, dispatcher);

            touchProcessor.PointerDown  += OnPointerDown;
            touchProcessor.PointerMoved += OnPointerMoved;
            touchProcessor.PointerUp    += OnPointerUp;
            touchProcessor.Start();
        }