Warn about supported locales that lack localizations (#23850)
diff --git a/packages/flutter/lib/src/cupertino/localizations.dart b/packages/flutter/lib/src/cupertino/localizations.dart
index 05e4783..ce15d66 100644
--- a/packages/flutter/lib/src/cupertino/localizations.dart
+++ b/packages/flutter/lib/src/cupertino/localizations.dart
@@ -213,6 +213,9 @@
@override
bool shouldReload(_CupertinoLocalizationsDelegate old) => false;
+
+ @override
+ String toString() => 'DefaultCupertinoLocalizations.delegate(en_US)';
}
/// US English strings for the cupertino widgets.
diff --git a/packages/flutter/lib/src/material/material_localizations.dart b/packages/flutter/lib/src/material/material_localizations.dart
index 5927243..9fa3798 100644
--- a/packages/flutter/lib/src/material/material_localizations.dart
+++ b/packages/flutter/lib/src/material/material_localizations.dart
@@ -338,6 +338,9 @@
@override
bool shouldReload(_MaterialLocalizationsDelegate old) => false;
+
+ @override
+ String toString() => 'DefaultMaterialLocalizations.delegate(en_US)';
}
/// US English strings for the material widgets.
diff --git a/packages/flutter/lib/src/widgets/app.dart b/packages/flutter/lib/src/widgets/app.dart
index 3727486..ed6d941 100644
--- a/packages/flutter/lib/src/widgets/app.dart
+++ b/packages/flutter/lib/src/widgets/app.dart
@@ -5,6 +5,7 @@
import 'dart:async';
import 'dart:ui' as ui show window;
+import 'package:flutter/foundation.dart';
import 'package:flutter/rendering.dart';
import 'banner.dart';
@@ -769,6 +770,53 @@
// BUILDER
+ bool _debugCheckLocalizations(Locale appLocale) {
+ assert(() {
+ final Set<Type> unsupportedTypes =
+ _localizationsDelegates.map<Type>((LocalizationsDelegate<dynamic> delegate) => delegate.type).toSet();
+ for (LocalizationsDelegate<dynamic> delegate in _localizationsDelegates) {
+ if (!unsupportedTypes.contains(delegate.type))
+ continue;
+ if (delegate.isSupported(appLocale))
+ unsupportedTypes.remove(delegate.type);
+ }
+ if (unsupportedTypes.isEmpty)
+ return true;
+
+ // Currently the Cupertino library only provides english localizations.
+ // Remove this when https://github.com/flutter/flutter/issues/23847
+ // is fixed.
+ if (listEquals(unsupportedTypes.map((Type type) => type.toString()).toList(), <String>['CupertinoLocalizations']))
+ return true;
+
+ final StringBuffer message = StringBuffer();
+ message.writeln('\u2550' * 8);
+ message.writeln(
+ 'Warning: This application\'s locale, $appLocale, is not supported by all of its\n'
+ 'localization delegates.'
+ );
+ for (Type unsupportedType in unsupportedTypes) {
+ // Currently the Cupertino library only provides english localizations.
+ // Remove this when https://github.com/flutter/flutter/issues/23847
+ // is fixed.
+ if (unsupportedType.toString() == 'CupertinoLocalizations')
+ continue;
+ message.writeln(
+ '> A $unsupportedType delegate that supports the $appLocale locale was not found.'
+ );
+ }
+ message.writeln(
+ 'See https://flutter.io/tutorials/internationalization/ for more\n'
+ 'information about configuring an app\'s locale, supportedLocales,\n'
+ 'and localizationsDelegates parameters.'
+ );
+ message.writeln('\u2550' * 8);
+ debugPrint(message.toString());
+ return true;
+ }());
+ return true;
+ }
+
@override
Widget build(BuildContext context) {
Widget navigator;
@@ -874,12 +922,16 @@
);
}
+ final Locale appLocale = widget.locale != null
+ ? _resolveLocale(widget.locale, widget.supportedLocales)
+ : _locale;
+
+ assert(_debugCheckLocalizations(appLocale));
+
return MediaQuery(
data: MediaQueryData.fromWindow(ui.window),
child: Localizations(
- locale: widget.locale != null
- ? _resolveLocale(widget.locale, widget.supportedLocales)
- : _locale,
+ locale: appLocale,
delegates: _localizationsDelegates.toList(),
child: title,
),
diff --git a/packages/flutter/lib/src/widgets/localizations.dart b/packages/flutter/lib/src/widgets/localizations.dart
index d2c1f44..459a34c 100644
--- a/packages/flutter/lib/src/widgets/localizations.dart
+++ b/packages/flutter/lib/src/widgets/localizations.dart
@@ -181,6 +181,9 @@
@override
bool shouldReload(_WidgetsLocalizationsDelegate old) => false;
+
+ @override
+ String toString() => 'DefaultWidgetsLocalizations.delegate(en_US)';
}
/// US English localizations for the widgets library.
diff --git a/packages/flutter_localizations/lib/src/material_localizations.dart b/packages/flutter_localizations/lib/src/material_localizations.dart
index 95151ce..f56b840 100644
--- a/packages/flutter_localizations/lib/src/material_localizations.dart
+++ b/packages/flutter_localizations/lib/src/material_localizations.dart
@@ -641,4 +641,7 @@
@override
bool shouldReload(_MaterialLocalizationsDelegate old) => false;
+
+ @override
+ String toString() => 'GlobalMaterialLocalizations.delegate(${kSupportedLanguages.length} locales)';
}
diff --git a/packages/flutter_localizations/lib/src/widgets_localizations.dart b/packages/flutter_localizations/lib/src/widgets_localizations.dart
index 45d7522..4150e19 100644
--- a/packages/flutter_localizations/lib/src/widgets_localizations.dart
+++ b/packages/flutter_localizations/lib/src/widgets_localizations.dart
@@ -74,4 +74,7 @@
@override
bool shouldReload(_WidgetsLocalizationsDelegate old) => false;
+
+ @override
+ String toString() => 'GlobalWidgetsLocalizations.delegate(all locales)';
}
