在Riverpod中执行此操作的首选方法是使用FutureProvider和AsyncValue：

final notificationRepositoryProvider = FutureProvider<bool?>((ref) async {
  Future<bool> approveDocument() => Future.delayed(Duration(seconds: 2), () => Future.value(Random().nextBool()));

  return approveDocument();
});

class HomeView extends ConsumerStatefulWidget {
  const HomeView({Key? key}) : super(key: key);

  @override
  HomeViewState createState() => HomeViewState();
}

class HomeViewState extends ConsumerState<HomeView> {
  @override
  Widget build(BuildContext context) {
    AsyncValue<bool?> rejectResponse = ref.watch(notificationRepositoryProvider);
    return ElevatedButton(
        onPressed: () {
         ref.refresh(notificationRepositoryProvider.future);
        },
        child: rejectResponse.when(
          loading: () => const CircularProgressIndicator(
            color: Colors.white,
          ),
          skipLoadingOnRefresh: false,
          error: (err, stack) => Text('Error'),
          data: (data) => Text('Yes: $data'),
        ));
  }
}

请注意，在初始加载之后，FutureProvider将为return the previous value but will set AsyncValue.isRefreshing to true。为了避免这种情况并始终在刷新时显示加载器，可以将skipLoadingOnRefresh设置为false。

你可以使用ConnectionState，但我认为它也可以处于none状态，所以你可以检查它是否完成，如果没有，你可能应该显示加载指示器。

builder: (context, snapshot) {
   if (snapshot.connectionState != ConnectionState.done) {
      return CircularProgressIndicator();
   } 
   else 
      return Text('Yes');
   } 
}

我通常使用hasData属性来代替，这样可以减少必须处理的状态数，并且可以安全地假设snapshot.data不是null。

// strongly type the builder so snapshot.data is typed as well.
FutureBuilder<MyType>( 
    future: myFuture
    builder: (context, snapshot) {
       if (!snapshot.hasData) return Loading();

       final data = snapshot.data!; // '!' is safe since hasData is true
       return DisplayData(data);
    }
)