使用build方法使用changeNotifier提供商对象的最佳方法是什么？

Question

我有一个 flutter 应用程序，并且不断收到错误，其中指出：

The following assertion was thrown while dispatching notifications for UserData:
setState() or markNeedsBuild() called during build.

UserData 是扩展 ChangeNotifier 的类，并且当我调用 notifyListeners() 方法时会引发此异常。

我的视图

class MyViewextends StatefulWidget {
  @override
  _MyViewState createState() => _MyViewState();
}

class _MyViewState extends State<MyView> {
  @override
  Widget build(BuildContext context) {
    return FutureBuilder(
        future: UserService().getUser(),
        builder: (context, snapshot) {
          if (snapshot.connectionState == ConnectionState.done)
            {
              var userData = Provider.of<UserData>(context, listen: false);
              var user = (snapshot.data as ApiResponseModel)?.entity;
              userData.set(user); //this is where the error gets thrown
            }

          return Container(); 
          //shortened for question purposes. Ideally, I will be printing the User objects to the container. 
          //It containers String properties like firstName, lastName.
        });
  }
}

UserData

class UserData extends ChangeNotifier{
  UserDto user;

  void set(UserDto userDto){
    user = userDto;
    notifyListeners();
  }

我想知道的是，有什么更好的方法可以初始化我的 UserDto 对象，这样就不会抛出此错误？

在我看来，if 块最有意义，但显然不是。