Extjs grid combo

 {
                        xtype: 'gridcolumn',
                        text: '非正常项',
                        dataIndex: 'UnusualItem',
                         60,
                        hidden: me.extOptions.isUsual == 'Usual' ? true : false,
                        editor: {
                            xtype: 'combobox',
                            alias: 'widget.xXYYZZ',
                            //                labelAlign: 'right',
                            itemId: 'UnusualItemId',
                            triggerAction: 'all',
                            store: new Ext.data.SimpleStore
                                    ({
                                        fields: ["val", "lab"],
                                        data: [[0, '张三'], [1, '李四'], [2, '王五']]
                                    }),
                            mode: 'local',
                            forceSelection: true,
                            editable: false,
                            valueField: 'val',
                            displayField: 'lab',
                            emptyText: '请选择',
                            defaultListConfig: { loadMask: false }
                        }