Flutter - Using GetIt with BuildContext

I'm using Localizations in my app based on the flutter documentation.
See here: https://flutter.dev/docs/development/accessibility-and-localization/internationalization

I use get_it package (version 4.0.4) to retrieve singleton objects like the Localization delegate. Unfortunately it needs a BuildContext property. Sometimes in my app I don't have the context reference so it would be nice if it would work like this: GetIt.I<AppLocalizations>() instead of this: AppLocalizations.of(context). It still can be achieved without a problem if you setup get_it like this: GetIt.I.registerLazySingleton(() => AppLocalizations.of(context)); The problem is that you need the context at least once to make it work. Moreover if you would like to display a localized text instantly in your initial route it's more difficult to get a properly initialized BuildContext at a time when you need it.

It's a little hard for me to explain it properly so I recreated the issue in a minimal example.

I commented out some code that would cause compile time errors, but it shows how I imagined it to be done.

main.dart

GetIt getIt = GetIt.instance;

void setupGetIt() {
  // How to get BuildContext properly if no context is available yet?
  // Compile time error.
  // getIt.registerLazySingleton(() => AppLocalizations.of(context));
}

void main() {
  setupGetIt();

  runApp(MyApp());
}

class MyApp extends StatefulWidget {
  MyApp({Key key}) : super(key: key);

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

class _MyAppState extends State<MyApp> {
  @override
  Widget build(BuildContext context) {
    // The above line also won't work. It has BuildContext but Applocalizations.of(context) won't work
    // because it's above in the Widget tree and not yet setted up.
    getIt.registerLazySingleton(() => AppLocalizations.of(context));
    return MaterialApp(
      supportedLocales: const [
        Locale('en', 'US'),
        Locale('hu', 'HU'),
      ],
      localizationsDelegates: const [
        AppLocalizations.delegate,
        GlobalMaterialLocalizations.delegate,
        GlobalWidgetsLocalizations.delegate,
        GlobalCupertinoLocalizations.delegate,
      ],
      localeResolutionCallback: (locale, supportedLocales) {
        // check if locale is supported
        for (final supportedLocale in supportedLocales) {
          if (supportedLocale.languageCode == locale?.languageCode &&
              supportedLocale.countryCode == locale?.countryCode) {
            return supportedLocale;
          }
        }
        // if locale is not supported then return the first (default) one
        return supportedLocales.first;
      },
      // You may pass the BuildContext here for Page1 in it's constructor 
      // but in a more advanced routing case it's not a maintanable solution.
      home: Page1(),
    );
  }
}

Initial route

class PageBase extends StatelessWidget {
  final String title;
  final Widget content;

  PageBase(this.title, this.content);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(title),
      ),
      body: content,
    );
  }
}

class Page1 extends PageBase {
  // It won't run because I need the context but clearly I don't have it.
  // And in a real app you also don't want to pass the context all over the place 
     if you have many routes to manage.
  Page1(String title)
      : super(AppLocalizations.of(context).title, Center(child: Text('Hello')));

  // Intended solution
  // I don't know how to properly initialize getIt AppLocalizations singleton by the time
  // it tries to retrieve it
  Page1.withGetIt(String title)
      : super(getIt<AppLocalizations>().title, Center(child: Text('Hello')));
}

locales.dart

String globalLocaleName;

class AppLocalizations {
  //AppLocalizations(this.localeName);

  static AppLocalizations of(BuildContext context) {
    return Localizations.of<AppLocalizations>(context, AppLocalizations);
  }

  static const LocalizationsDelegate<AppLocalizations> delegate =
      _AppLocalizationsDelegate();

  static Future<AppLocalizations> load(Locale locale) async {
    final String name =
        locale.countryCode.isEmpty ? locale.languageCode : locale.toString();

    final String localeName = Intl.canonicalizedLocale(name);

    return initializeMessages(localeName).then((_) {
      globalLocaleName = localeName;
      return AppLocalizations();
    });
  }

  String get title => Intl.message(
        'This is the title.',
        name: 'title',
      );
}

class _AppLocalizationsDelegate
    extends LocalizationsDelegate<AppLocalizations> {
  // This delegate instance will never change (it doesn't even have fields!)
  // It can provide a constant constructor.
  const _AppLocalizationsDelegate();

  @override
  bool isSupported(Locale locale) {
    return ['en', 'hu'].contains(locale.languageCode);
  }

  @override
  Future<AppLocalizations> load(Locale locale) => AppLocalizations.load(locale);

  @override
  bool shouldReload(_AppLocalizationsDelegate old) => false;
}

And some intl generated dart code and .arb files that is not so important to illustrate the problem.

So all in all, how can I achive to use my AppLocalizations class as a singleton without using a context for example in a situation like this? Maybe my initial approach is bad and it can be done in other ways that I represented. Please let me know if you have a solution.

Thank you.