Unity EventSystem.current.IsPointerOverGameObject() 真機BUG

版本號：**2017.4.29f **

判斷是否點擊\觸摸在UI上所調用的 EventSystem.current.IsPointerOverGameObject() 接口有問題，在真機無法返回正確判斷。

處理辦法：
1、UI事件發出射線檢測

    public static bool IsPointerOverGameObject()
    {
        PointerEventData eventData = new PointerEventData(UnityEngine.EventSystems.EventSystem.current);
        eventData.pressPosition = Input.mousePosition;
        eventData.position = Input.mousePosition;

        List<RaycastResult> list = new List<RaycastResult>();
        UnityEngine.EventSystems.EventSystem.current.RaycastAll(eventData, list);

        return list.Count > 0;
    }

2、Canvas的GraphicRaycaster發出射線檢測

    public bool IsPointerOverGameObject(Canvas canvas)
    {
        PointerEventData eventData = new PointerEventData(EventSystem.current);
        eventData.pressPosition = Input.mousePosition;
        eventData.position = Input.mousePosition;

        GraphicRaycaster uiRaycaster = canvas.gameObject.GetComponent<GraphicRaycaster>();

        List<RaycastResult> results = new List<RaycastResult>();
        uiRaycaster.Raycast(eventData, results);

        return results.Count > 0;
    }