extjs grid json

[拉唯达]

{

"currdate": null,
"errMsg": "",
"errNo": 0,
"listData": [
{
"a00OldJsonValue": null,
"code": "0002",
"deprrate": 0,
"deprvalue": 0,
"id": 2,
"locked": false,
"name": "房子",
"total": 12,
"usedall": 0,
"wlflag": false,
"workload": 10,
"yearmon": "201508"
},
{
"a00OldJsonValue": null,
"code": "111",
"deprrate": 0,
"deprvalue": 0,
"id": 4,
"locked": false,
"name": "fangzi",
"total": 20,
"usedall": 10,
"wlflag": false,
"workload": 2,
"yearmon": "201508"
}


url:"common/workload/workloadList!doGetListData.action"
extjs我在界面怎么用grid获取数据啊 初学 求帮忙