我在一个ondemand网格中有一个dijit表单复选框。Ondemand网格是一个dojo小部件的一部分。我想在复选框的on change事件中调用小部件中的一个函数，但是我似乎无法获得对小部件的引用。下面是我的代码：

TicketUnMarkedSet: function (GridData) {

        //set the unmarked ticket information
        gridStore = new Memory({ data: GridData, idProperty: "ID" });
        grid = new (declare([OnDemandGrid, DijitRegistry]))({
            store: gridStore,
            columns: {
                CheckedOut: {
                    label: "CO",
                    renderCell: function (object, cell) {
                        var CO = true; // check the checked out check box based on data from db
                        if (object.CheckedOut == "No") {
                            CO = false;
                        }
                        var cellContent = domConstruct.create("div", {});
                        var cbox = new CheckBox({
                            checked: CO,
                            name: "idBox"
                        });
                        cbox.placeAt(cellContent);
                        on(cbox, "change", function (evt) {
                            var Staff = "No";
                            if (evt == true) {//check box is checked, flag ticket as checked out
                                Staff = cookie("LoggedInAs")
                            }

                        this.CheckOutTicket(Staff);//how to call CheckOutTicket function (this is the checkbox)

                        });
                        return cellContent;
                    }
                },
     ..more columns
},
CheckOutTicket: function (Staff){
  alert(Staff);
}

我怎样才能获得CheckOutTicket函数的引用？
谢啦，谢啦
皮特