NavigatorWithAuth

navigator_with_auth_02.dart

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  MyAppRouterDelegate delegate;
  AuthRepository authRepository;

  @override
  void initState() {
    delegate = MyAppRouterDelegate(AuthRepository(Preference()));
    authRepository = AuthRepository(Preference());
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return ChangeNotifierProvider<AuthViewModel>(
      create: (_) => AuthViewModel(authRepository),
      child: MaterialApp(home: Router(routerDelegate: delegate)),
    );
  }
}

Why duplicate creation of the instances, and instead:

  @override
  void initState() {
    delegate = MyAppRouterDelegate(AuthRepository(Preference()));
    authRepository = AuthRepository(Preference());
    super.initState();
  }

write

  @override
  void initState() {
    var preference = Preference()
    authRepository = AuthRepository(preference);
    delegate = MyAppRouterDelegate(authRepository);
    super.initState();
  }

?