TouchPanel.IsGestureAvailable() is always false

代码如下调试器进入handinput区域，但从不清除触摸面板。即使我们轻触屏幕，手势也是可用的谢谢你的帮助:)

 #region Handle Input
        public override void HandleInput(InputState input)
        {
            Debug.WriteLine("hey stackoverflow'n");
            if (TouchPanel.IsGestureAvailable)
            {
                Debug.WriteLine("check presence'n");
                // read the next gesture
                var gesture = TouchPanel.ReadGesture();
                if (gesture.GestureType == GestureType.Tap | gesture.GestureType == GestureType.Flick | gesture.GestureType == GestureType.Hold)
                {
                // code sample
                }
            }
            base.HandleInput(input);
        }
        #endregion

请帮忙做这件事已经两天了!!!!!