ext grid 中怎样显示ComboBox

{ header: "所属供应商", width: 150, dataIndex : 'purveyModuleId' ,  editor: purveyModuleId,renderer: function(v){var rec = this.editor.getStore().getAt(v);if (rec == null) {return v;} else {return rec.data[this.editor.displayField];}}},

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