extjs baseCombo 通过后台查询数据赋值到下拉列表

js代码：

var fields =[{        fieldLabel: '报告编号',        name: 'report_id',        id:'report_id',        emptyText:'报告编号',        xtype:'baseCombo',        sUrl:"brwper/queryTDReport",        params:{'bid':this.params.bid},        fields:{key:{name:'report_id'},value:{name:'report_id'}},        width:310,        margin:'0 15px 5px 10px'    }];

java代码：

List<String> reportS = service.findReportId(b_id);    List<Map<String,Object>> reportList = new ArrayList<Map<String,Object>>();    for(String str:reportS){    Map<String,Object> reportMap = new HashMap<String, Object>();    reportMap.put("report_id", str);    reportList.add(reportMap);    }    map.put("items", reportList);    map.put("success", true);    return map;

要注意要求的数据结构：

是list里面放的map，通过key value赋值