easyui datagrid中关联combox

datagrid中列上关联combobox
{ field: 'SysCode', title: '系统代码', width: 150, align: 'left', editor: {
                            type: 'combobox',
                            options:
                                {
                                    valueField: 'id',
                                    textField: '要显示的字段名',
                                    url: '/Sys/SearchCodeInFunctionModel',
                                }
                        }

< th  data-options="field:'fShipCom',width:100,align:'center',
                                    formatter:function(value,row){
                                        return row.fShipCom;
                                    },
                                    editor:{
                                        type:'combobox',
                                        options:{
                                            valueField:'fShipCom',
                                            textField:'fShipCom',
                                            url:'ShipPlan.ashx? act = getShipCom ',
                                             onChange :function(value){

                                                var tr = $(this).closest('tr.datagrid-row');
                                                 var idx = parseInt(tr.attr('datagrid-row-index'));
                                                 var ed = $('#dg').datagrid('getEditor',{index:0, field:'fShipName'});
                                                alert(idx);
                                                alert(value);

                                                $(ed.target).combobox('reload','ShipPlan.ashx? act = getShipName &fshipCom='+escape(value));


                                                },
                                            required:true
                                        }
                                    }">船公司</ th >