UGUI 点击穿透问题

unity上 用 做游戏欢迎界面上通用的ui，然后导到游戏里面直接用，但发现游戏里面是用ngui的，点击ugui 的ui 会穿透过去 ngui会响应，原本模型的点击处理也会响应

我用的 unity 版本 是 4.6.3的

本来是用   EventSystem.current.IsPointerOverGameObject()   来检测点击穿透的

在pc的unity编辑器上都可以检测到。可是打包到android 上 就无效，网上有的说以前的版本可以，不知道是不是之后的bug，还是有其他的接口

在网上搜到了这里，找到以下解决方法：

    /// <summary>
    /// Cast a ray to test if Input.mousePosition is over any UI object in EventSystem.current. This is a replacement
    /// for IsPointerOverGameObject() which does not work on Android in 4.6.0f3
    /// </summary>
    private static bool IsPointerOverUIObject()
    {
        if (EventSystem.current == null)
            return false;

        // Referencing this code for GraphicRaycaster https://gist.github.com/stramit/ead7ca1f432f3c0f181f
        // the ray cast appears to require only eventData.position.
        PointerEventData eventDataCurrentPosition = new PointerEventData(EventSystem.current);
        eventDataCurrentPosition.position = new Vector2(Input.mousePosition.x, Input.mousePosition.y);

        List<RaycastResult> results = new List<RaycastResult>();
        EventSystem.current.RaycastAll(eventDataCurrentPosition, results);

        return results.Count > 0;
    }

    /// <summary>
    /// Cast a ray to test if screenPosition is over any UI object in canvas. This is a replacement
    /// for IsPointerOverGameObject() which does not work on Android in 4.6.0f3
    /// </summary>
    private bool IsPointerOverUIObject(Canvas canvas, Vector2 screenPosition)
    {
        if (EventSystem.current == null)
            return false;

        // Referencing this code for GraphicRaycaster https://gist.github.com/stramit/ead7ca1f432f3c0f181f
        // the ray cast appears to require only eventData.position.
        PointerEventData eventDataCurrentPosition = new PointerEventData(EventSystem.current);
        eventDataCurrentPosition.position = screenPosition;

        GraphicRaycaster uiRaycaster = canvas.gameObject.GetComponent<GraphicRaycaster>();
        List<RaycastResult> results = new List<RaycastResult>();
        uiRaycaster.Raycast(eventDataCurrentPosition, results);
        return results.Count > 0;
    }