如何在SAPUI5智能表中展开多列？

<mvc:View
    controllerName="your.controller.namespace"
    xmlns:mvc="sap.ui.core.mvc"
    xmlns="sap.m">
    <SmartTable id="smartTable" entitySet="Products" useVariantManagement="false" useTablePersonalisation="true" header="Products">
        <columns>
            <Column>
                <Label text="Name"/>
            </Column>
            <Column>
                <Label text="Price"/>
            </Column>
            <Column>
                <Label text="Quantity"/>
            </Column>
        </columns>
    </SmartTable>
</mvc:View>

sap.ui.define([
    "sap/ui/core/mvc/Controller",
    "sap/ui/model/json/JSONModel"
], function(Controller, JSONModel) {
    "use strict";

    return Controller.extend("your.controller.namespace", {
        onInit: function() {
            var oModel = new JSONModel();
            oModel.setData({
                "Products": [
                    { "Name": "Product A", "Price": 100, "Quantity": 5 },
                    { "Name": "Product B", "Price": 200, "Quantity": 10 }
                ]
            });
            this.getView().setModel(oModel);

            var oSmartTable = this.byId("smartTable");
            var oColumns = oSmartTable.getColumns();
            oColumns.forEach(function(oColumn) {
                oColumn.setExpanded(true); // 展开所有列
            });
        }
    });
});