dart - 如何通过 json 结果在 Dart 中更新选项

Question

我的选项值是从服务器下载的。服务器返回结果后如何更新选项值？

 <select name="book" template iterate="book in books" bind-value="selected">
 <option selected="{{selected == book}}">{{book}}</option>
 </select>

在 .dart

 List<String> books= <String>[''];
 @observable
 String selected = 'Doraemon';
 void main() {
      var request = HttpRequest.getString(url).then((jstr){
      // Parse json
      Map data = json.parse(jstr);
      print(data['option']['books']);
      // Refresh the list, but how to refresh option value?
      books.addAll(data['option']['books']);
 }

Answer 1

您应该将书籍价值包装在对“toObservable”的调用中。https://www.dartlang.org/web-ui/observables/#observing-collections

List<String> books= toObservable(<String>['']);