GridPanel加载的时候没有Loading效果

我在页面上放置了一个GridPanel，但是第一次加载的时候不显示Loading的效果，只有翻页的时候才有loading效果。请各位高手帮忙看看 
代码如下

JScript code
var admingrid = new Ext.grid.GridPanel({
        id: "admingrid",
        store: adminStore,
        sm: adminsm,
        cm: admincm,
        autoScroll: true,
        autoExpandColumn: 7,
        autoWidth: true,
        border: false,
        height: 180,
        loadMask: true,
        viewConfig: {
            columnsText: "显示/隐藏列",
            sortAscText: "正序排列",
            sortDescText: "倒序排列",
            forceFit: true
        },
        //分页
        bbar: [new Ext.PagingToolbar({
            store: adminStore,
            pageSize: pageSize,
            emptyMsg: "No result to display",
            prevText: "上一页",
            nextText: "下一页",
            refreshText: "刷新",
            lastText: "最后页",
            firstText: "第一页",
            beforePageText: "当前页",
            afterPageText: "共{0}页"
        }), new Ext.Toolbar.Fill()],
        tbar: [{
            text: "添加",
            tooltip: "添加管理员",
            iconCls: "addicon",
            handler: addAdmin
        }, "", "-", "", {
            text: "编辑",
            tooltip: "编辑管理员",
            iconCls: "editicon",
            handler: editAdminFn
        }, "", "-", "", {
            text: "删除",
            tooltip: "删除管理员",
            iconCls: "deleteicon",
            handler: deleteAdminFn
        }, "-", new Ext.Toolbar.Fill()],
        listeners: {
            'contextmenu': function(e) {
                e.stopEvent();
            },
            'rowcontextmenu': function(grid, rowIndex, e) {
                e.stopEvent();
            }
        },loadMask:{msg:'正在加载数据...'}
    });

正确答案是。grid只有先render再load数据才有那个效果。。。楼主自己看看自己是不是这个顺序