Flutter - 从 Firestore 获取数据并在应用启动时保存到 Provider

如何解决Flutter - 从 Firestore 获取数据并在应用启动时保存到 Provider

我需要从 Firestore 获取一些数据，并在应用首次打开时将其保存到 Provider。

这是加载的第一个页面。这是一个有状态的小部件，我正在尝试像这样获取数据：

@override
  void initState() {
    super.initState();
    final User user = Provider.of<User>(context,listen: false);
    _getItems(user);
  }

  _getItems(user) {
    final content = Provider.of<Content>(context,listen: false);
    //get data from Firestore using user.uid
    //save it to content.ids
    content.ids = {"1": 2};
  }

执行此操作时，我收到以下错误：

Flutter: The following assertion was thrown while dispatching notifications for Content:
Flutter: setState() or markNeedsBuild() called during build.
Flutter: This _InheritedProviderScope<Content> widget cannot be marked as needing to build because the
Flutter: framework is already in the process of building widgets.  A widget can be marked as needing to be
Flutter: built during the build phase only if one of its ancestors is currently building. This exception is
Flutter: allowed because the framework builds parent widgets before children,which means a dirty descendant
Flutter: will always be built. Otherwise,the framework might not visit this widget during this build phase.
Flutter: The widget on which setState() or markNeedsBuild() was called was:
Flutter:   _InheritedProviderScope<Content>

在应用程序启动时获取数据并保存到 Provider 的最佳方式是什么？我知道我在 MultiProvider 中有 main.dart 选项，但我在那里没有用户 ID。