Flutter：streamprovider 显示小吃店

Question

我很难创建一个 StreamProvider。我想在连接离线时显示小吃店。

为此，我创建了一个 StreamProvider，它会在值更改时通知小部件。

但我不知道把我的小部件放在哪里来显示刷新栏（改进的小吃栏）。

我现在有：

我的连接服务：

class ConnectivityService {
  ConnectivityService._privateConstructor();

  static final ConnectivityService instance =
      ConnectivityService._privateConstructor();

  StreamController<ConnectionStatus> connectionStatusController =
      StreamController<ConnectionStatus>();

  ConnectivityService() {
    Connectivity()
        .onConnectivityChanged
        .listen((ConnectivityResult result) async {
      bool isDeviceConnected = false;
      if (result != ConnectivityResult.none) {
        isDeviceConnected = await DataConnectionChecker().hasConnection;
      }

      connectionStatusController.add(isDeviceConnected == true
          ? ConnectionStatus.Online
          : ConnectionStatus.Offline);
    });
  }
}

我的notifWidget

import 'dart:js';

import 'package:another_flushbar/flushbar_helper.dart';
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:wetip/Services/ConnectivityService.dart';

class NotifWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final connectStatus = Provider.of<ConnectionStatus>(context, listen: false);

    if (connectStatus == ConnectionStatus.Offline) {
      return Container(
        child: FlushbarHelper.createError(message: 'Offline'),
      );
    }
    return context.widget;
  }
}

我的 main.dart

我不知道把我的小部件放在哪里。我希望它在应用程序离线时每次在应用程序中显示flushbar（相当于snackbar）

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final Future initFuture = LauncherService.initialize(context);

    return StreamProvider<ConnectionStatus>(
        create: (context)=>ConnectivityService.instance.connectionStatusController.stream,
        initialData: ConnectionStatus.Online,
        child:NotifWidget(??? MaterialApp(
          title: L.Localize('App'),
          theme: MyTheme.defaultTheme,
          debugShowCheckedModeBanner: false,
          navigatorKey: navigatorKey,
          home: FutureBuilder(
              future: initFuture,
              builder: (context, snapshot) {
                if (snapshot.connectionState == ConnectionState.done) {
                  if (Globals.accessTokenManager.isUserLoggedIn) {
                  } else
                    return WelcomeOnBoardScreen();
                }
                return SplashScreen();
              }),
        ));
  }
}