FlutterBloc会阻止在热重启时出现多个实例？

我刚刚注意到，每当我热重启我的应用程序时，Chart的实例似乎就会堆积起来。我已附上一张图像，该图像显示每次热重启时，都会添加一个AuthBloc的实例。

以下是我在AuthBloc上的代码：

main.dart

为了重新启动热启动时void main() {
BlocSupervisor.delegate = SimpleBlocDelegate();
final userRepository = UserRepository();
runApp(
BlocProvider(
create: (context) {
return AuthBloc(userRepository: userRepository);
},child: MultiProvider(
providers: [
ChangeNotifierProvider(create: (context) => UserProvider()),ChangeNotifierProvider(create: (context) => UserTokenProvider()),],child: MainApp(userRepository: userRepository),),);
}
class MainApp extends StatefulWidget {
final UserRepository userRepository;
const MainApp({Key key,@required this.userRepository}) : super(key: key);
@override
_MainAppState createState() => _MainAppState();
}
class _MainAppState extends State {
@override
void initState() {
super.initState();
// WidgetsBinding.instance.addPostFrameCallback(
// (_) => new FirebaseMessagingController().initialize());
WidgetsBinding.instance.addPostFrameCallback((_) => _initializeAppStart());
}
@override
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedmodeBanner: false,home: Center(
child: LoginPage(
userRepository: widget.userRepository,);
}
_initializeAppStart() {
BlocProvider.of(context).add(AppStarted());
}
}
实例不会堆积，我该怎么做？