fix: 修复语言

Author: ILoveScratch2

lib/main.dart

@@ -245,6 +245,41 @@ class _StartupRecoveryResult {
   });
 }
 
+/// Provides Material localizations for the [och] language code by proxying
+/// to Simplified Chinese, since [GlobalMaterialLocalizations] does not support
+/// ISO 639-3 codes like [och].
+class _OchMaterialLocalizationsDelegate
+    extends LocalizationsDelegate<MaterialLocalizations> {
+  const _OchMaterialLocalizationsDelegate();
+
+  @override
+  bool isSupported(Locale locale) => locale.languageCode == 'och';
+
+  @override
+  Future<MaterialLocalizations> load(Locale locale) =>
+      GlobalMaterialLocalizations.delegate.load(const Locale('zh'));
+
+  @override
+  bool shouldReload(_OchMaterialLocalizationsDelegate old) => false;
+}
+
+/// Provides Cupertino localizations for the [och] language code by proxying
+/// to Simplified Chinese, for the same reason as [_OchMaterialLocalizationsDelegate].
+class _OchCupertinoLocalizationsDelegate
+    extends LocalizationsDelegate<CupertinoLocalizations> {
+  const _OchCupertinoLocalizationsDelegate();
+
+  @override
+  bool isSupported(Locale locale) => locale.languageCode == 'och';
+
+  @override
+  Future<CupertinoLocalizations> load(Locale locale) =>
+      GlobalCupertinoLocalizations.delegate.load(const Locale('zh'));
+
+  @override
+  bool shouldReload(_OchCupertinoLocalizationsDelegate old) => false;
+}
+
 class TouchFishApp extends StatefulWidget {
   final bool isFirstLaunch;
   final bool hasSavedSession;
@@ -499,10 +534,12 @@ class _TouchFishAppState extends State<TouchFishApp> {
 
         return MaterialApp.router(
           routerConfig: _router,
-          onGenerateTitle: (context) => AppLocalizations.of(context)!.appName,
+          onGenerateTitle: (context) => AppLocalizations.of(context)?.appName ?? '',
           debugShowCheckedModeBanner: false,
           localizationsDelegates: const [
             AppLocalizations.delegate,
+            _OchMaterialLocalizationsDelegate(),
+            _OchCupertinoLocalizationsDelegate(),
             GlobalMaterialLocalizations.delegate,
             GlobalWidgetsLocalizations.delegate,
             GlobalCupertinoLocalizations.delegate,

lib/screens/settings_screen.dart

@@ -1006,6 +1006,8 @@ class _SettingsScreenState extends State<SettingsScreen>
         return l10n.settingsLanguageZh;
       case 'settingsLanguageEn':
         return l10n.settingsLanguageEn;
+      case 'settingsLanguageCc':
+        return l10n.settingsLanguageCc;
       case 'settingsThemeTitle':
         return l10n.settingsThemeTitle;
       case 'settingsThemeDesc':