/// <summary>
    /// Changes the index of the app by.
    /// </summary>
    /// <param name="index">Index.</param>
    /// <param name="app">App.</param>
    void ChangeAppByIndex(int index, App app)
    {
        appList.RemoveAt(index);
        appList.Insert(index, app);
        GameObject     icon           = pageChildList [index];
        IconController iconController = icon.GetComponent <IconController> ();

        iconController.setApp(app);
    }
    public void addPlaceholder(int pageNum, int index, Location location)
    {
        App app = new App();

        app.SetIsPlaceholder(true);
        appList.Insert(index, app);

        GameObject     pageLayout  = pageList [pageNum];
        GameObject     pageChild   = Instantiate(pageChildPrefab);
        IconController iconControl = pageChild.GetComponent <IconController> ();

        iconControl.setApp(app);
        PageLayout pageControl = pageLayout.GetComponent <PageLayout> ();

        iconControl.originLocation = location;
        pageControl.addChild(pageChild, iconControl.originLocation.position3D, new Vector2(launcherModel.itemWidth, launcherModel.itemHeight));
        pageChildList.Insert(index, pageChild);
    }
    void LoadAppIcon(int beginIndex, int endIndex)
    {
        int        left        = 0;
        int        bottom      = 0;
        int        curPage     = 0;
        int        curRow      = 0;
        int        pageItemNum = launcherModel.pageItemNum;
        int        columnNum   = launcherModel.columnNum;
        int        itemWidth   = launcherModel.itemWidth;
        int        itemHeight  = launcherModel.itemHeight;
        int        pageHeight  = launcherModel.screenHeight;
        GameObject pageLayout  = null;
        int        appNum      = endIndex;

        for (int i = beginIndex; i < appNum; i++)
        {
            curPage = i / pageItemNum;
            curRow  = i % pageItemNum / columnNum;
            if (i % columnNum == 0)
            {
                left = 0;
            }
            else
            {
                left = itemWidth;
            }
            bottom     = curRow * itemHeight;
            pageLayout = pageList [curPage];
            GameObject     pageChild   = Instantiate(pageChildPrefab);
            IconController iconControl = pageChild.GetComponent <IconController> ();

            App app = appList [i];
            iconControl.setApp(app);
            Vector3 pos3D = new Vector3(left, pageHeight - bottom - launcherModel.itemHeight, 0f);

            PageLayout pageControl = pageLayout.GetComponent <PageLayout> ();
            //			Debug.Log ("LoadAppIcon left="+left+" top="+bottom);
            iconControl.originLocation = new Location(pageControl.pageNumber, pos3D, i);
            pageControl.addChild(pageChild, pos3D, new Vector2(itemWidth, itemHeight));
            pageChildList.Add(pageChild);
        }
    }