使用cell做下拉列表时，循环数组输出，不能即时同步页面

``` html

import { Group, XTextarea, XButton, Checklist, Cell, CellBox } from "vux";
import http from "@/service/http/index";

export default {
components: {
Group,
XTextarea,
XButton,
Checklist,
Cell,
CellBox
},
data() {
return {
provinces: [
{
name: null,
projectDtos: [
{ xmId: "1", xmjc: "项目1" },
{ xmId: "2", xmjc: "项目2" }
]
}
]
};
},
methods: {
},
created() {
}
};

```