Rethinking localization in Flutter

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I do use intl_utils as i thought that were the ‘official’ way of doing this.
But as i never had problems with my approach, so it may help some of you too.
In short, this solution don’t has to pass a BuildContext around.

First of all, my localization is retrieved through the context via S.of(context); (S are my AppLocalizations)

And hence i have a class, i created an interface

import "../../../generated/l10n.dart";

//ignore: one_member_abstracts .
abstract class Localizable<T> {
  T localize(S s);
}

So, i’ve created a LocalizableException


abstract class LocalizableException implements Localizable<String>, Exception {
  /// {@template shared.logic.localizable_exception}
  /// will be shown instead of [getMessage].
  /// For example: A network call returns a more specific exception message than the default localized message
  /// {@endtemplate}
  final String? message;

  const LocalizableException({this.message});

  /// a default localized message
  @mustBeOverridden
  String getMessage(S s) => throw UnimplementedError();

  /// show the message provided by the exception thrower, if any. Otherwise a fallback is provided by [getMessage].
  @override
  String localize(S s, {bool ignoreOverride = false}) {
    if (message != null && ignoreOverride) return message!;

    return getMessage(s);
  }
}

With that, exceptions thrown in my business logic are piped through a message queue and can than be listened by inherited widgets or other ‘consumers’.
This way, my UI is retrieving my exceptions and can correctly localize them.

 void _startUserErrorListener() {
    subscribe(
      queueId: Queue.userError.name,
      callback: (Message message) {
        SnackBar snackbar;

        switch (message) {
          case LocalizableMessage(payload: LocalizableException payload):
            snackbar = ErrorSnackbar.exception(
              context: scaffoldMessengerKey.currentContext!,
              exception: payload,
            );
          default:
            snackbar = ErrorSnackbar(
              context: scaffoldMessengerKey.currentContext!,
              message: message.payload.toString(),
            );
        }

        _showSnackbar(snackbar);
      },
    );
  }

I’ve seen other packages that don’t elevate the BuildContext and only use static localizations which i think is also fine in most apps, as i personally never had the case to localize a subtree differently.