i18n_multilanguage_with_flags 0.2.0

Generic Flutter i18n toolkit with language metadata, flag dropdowns, and language selection persistence.

example/lib/main.dart

import 'package:flutter/material.dart';
import 'package:i18n_multilanguage_with_flags/i18n_multilanguage_with_flags.dart';

import 'i18n/translation_keys.dart';
import 'i18n/translations/all_translations.dart';

void main() {
  runApp(const ExampleApp());
}

class ExampleApp extends StatefulWidget {
  const ExampleApp({super.key});

  @override
  State<ExampleApp> createState() => _ExampleAppState();
}

class _ExampleAppState extends State<ExampleApp> {
  late final I18nMultilanguageController _controller;
  final _storage = LanguageSelectionStorage();
  final _defaultCatalogMap = buildDefaultLanguageCatalogMap();

  @override
  void initState() {
    super.initState();
    _controller = I18nMultilanguageController(
      languages: buildConfigurableLanguageCatalog(
        includeIds: const ['en_us', 'pt_br'],
      ),
      initialUiLanguageId: 'en_us',
      initialSecondaryLanguageId: 'pt_br',
      translations: appTranslations,
    );
    _hydrate();
  }

  Future<void> _hydrate() async {
    await _controller.loadFromStorage(_storage);
    if (mounted) {
      setState(() {});
    }
  }

  @override
  void dispose() {
    _controller.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text(_controller.tr(TranslationKeys.appTitle)),
        ),
        body: AnimatedBuilder(
          animation: _controller,
          builder: (context, _) {
            return Column(
              children: [
                I18nPreferencesForm(
                  languages: _controller.languages,
                  initialUiLanguageId: _controller.uiLanguageId,
                  initialSecondaryLanguageId: _controller.secondaryLanguageId,
                  initialDisplayName: _controller.displayName,
                  showDisplayNameField: true,
                  requireSecondaryLanguage: true,
                  uiLanguageLabel:
                      _controller.tr(TranslationKeys.uiLanguageLabel),
                  secondaryLanguageLabel:
                      _controller.tr(TranslationKeys.secondaryLanguageLabel),
                  displayNameLabel:
                      _controller.tr(TranslationKeys.displayNameLabel),
                  displayNameHint:
                      _controller.tr(TranslationKeys.displayNameHint),
                  submitLabel: _controller.tr(TranslationKeys.submit),
                  onSubmit: (snapshot) async {
                    _controller.applySnapshot(snapshot);
                    await _controller.saveToStorage(_storage);
                  },
                ),
                const Divider(height: 1),
                Padding(
                  padding: const EdgeInsets.all(16),
                  child: Align(
                    alignment: Alignment.centerLeft,
                    child: Text(
                      '${_controller.tr(TranslationKeys.summary)}: '
                      '${_controller.uiLanguageId} / '
                      '${_controller.secondaryLanguageId ?? '-'} / '
                      '${_controller.displayName} / '
                      'langs=${_controller.languages.length}',
                    ),
                  ),
                ),
                const SizedBox(height: 8),
                Wrap(
                  spacing: 8,
                  runSpacing: 8,
                  children: [
                    OutlinedButton(
                      onPressed: () {
                        final spanish = _defaultCatalogMap['es_es'];
                        if (spanish == null) return;
                        _controller.upsertLanguage(spanish);
                      },
                      child: const Text('Add Spanish'),
                    ),
                    OutlinedButton(
                      onPressed: () {
                        _controller.removeLanguage('pt_br');
                      },
                      child: const Text('Remove Portuguese'),
                    ),
                  ],
                ),
                const SizedBox(height: 12),
              ],
            );
          },
        ),
      ),
    );
  }
}