判断是否存在UI被触摸

        if (Input.GetMouseButtonDown() || (Input.touchCount >  && Input.GetTouch().phase == TouchPhase.Began))
        {
#if UNITY_ANDROID || UNITY_IPHONE
            if (EventSystem.current.IsPointerOverGameObject(Input.GetTouch().fingerId))
#else
            if (EventSystem.current.IsPointerOverGameObject())
#endif
                Debug.Log("触摸");

            else
                Debug.Log("非触摸");
        }