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New locale resolution algorithm to use full preferred locale list, include scriptCode in Locale. (#23583)

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Gary Qian 2018-11-09 11:33:42 -08:00 committed by GitHub
parent 5071657e8e
commit dfd0229560
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6 changed files with 904 additions and 44 deletions
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7
packages/flutter/lib/src/cupertino/app.dart
View File

@ -90,6 +90,7 @@ class CupertinoApp extends StatefulWidget {
this.color,
this.locale,
this.localizationsDelegates,
this.localeListResolutionCallback,
this.localeResolutionCallback,
this.supportedLocales = const <Locale>[Locale('en', 'US')],
this.showPerformanceOverlay = false,
@ -157,6 +158,11 @@ class CupertinoApp extends StatefulWidget {
/// {@macro flutter.widgets.widgetsApp.localizationsDelegates}
final Iterable<LocalizationsDelegate<dynamic>> localizationsDelegates;
/// {@macro flutter.widgets.widgetsApp.localeListResolutionCallback}
///
/// This callback is passed along to the [WidgetsApp] built by this widget.
final LocaleListResolutionCallback localeListResolutionCallback;
/// {@macro flutter.widgets.widgetsApp.localeResolutionCallback}
///
/// This callback is passed along to the [WidgetsApp] built by this widget.
@ -283,6 +289,7 @@ class _CupertinoAppState extends State<CupertinoApp> {
locale: widget.locale,
localizationsDelegates: _localizationsDelegates,
localeResolutionCallback: widget.localeResolutionCallback,
localeListResolutionCallback: widget.localeListResolutionCallback,
supportedLocales: widget.supportedLocales,
showPerformanceOverlay: widget.showPerformanceOverlay,
checkerboardRasterCacheImages: widget.checkerboardRasterCacheImages,

7
packages/flutter/lib/src/material/app.dart
View File

@ -98,6 +98,7 @@ class MaterialApp extends StatefulWidget {
this.theme,
this.locale,
this.localizationsDelegates,
this.localeListResolutionCallback,
this.localeResolutionCallback,
this.supportedLocales = const <Locale>[Locale('en', 'US')],
this.debugShowMaterialGrid = false,
@ -264,6 +265,11 @@ class MaterialApp extends StatefulWidget {
/// <https://flutter.io/tutorials/internationalization/>.
final Iterable<LocalizationsDelegate<dynamic>> localizationsDelegates;
/// {@macro flutter.widgets.widgetsApp.localeListResolutionCallback}
///
/// This callback is passed along to the [WidgetsApp] built by this widget.
final LocaleListResolutionCallback localeListResolutionCallback;
/// {@macro flutter.widgets.widgetsApp.localeResolutionCallback}
///
/// This callback is passed along to the [WidgetsApp] built by this widget.
@ -423,6 +429,7 @@ class _MaterialAppState extends State<MaterialApp> {
locale: widget.locale,
localizationsDelegates: _localizationsDelegates,
localeResolutionCallback: widget.localeResolutionCallback,
localeListResolutionCallback: widget.localeListResolutionCallback,
supportedLocales: widget.supportedLocales,
showPerformanceOverlay: widget.showPerformanceOverlay,
checkerboardRasterCacheImages: widget.checkerboardRasterCacheImages,

235
packages/flutter/lib/src/widgets/app.dart
View File

@ -3,6 +3,7 @@
// found in the LICENSE file.
import 'dart:async';
import 'dart:collection' show HashMap;
import 'dart:ui' as ui show window;
import 'package:flutter/foundation.dart';
@ -24,19 +25,50 @@ import 'widget_inspector.dart';
export 'dart:ui' show Locale;
/// The signature of [WidgetsApp.localeListResolutionCallback].
///
/// A [LocaleListResolutionCallback] is responsible for computing the locale of the app's
/// [Localizations] object when the app starts and when user changes the list of
/// locales for the device.
///
/// The [locales] list is the device's preferred locales when the app started, or the
/// device's preferred locales the user selected after the app was started. This list
/// is in order of preference. If this list is null or empty, then Flutter has not yet
/// recieved the locale information from the platform. The [supportedLocales] parameter
/// is just the value of [WidgetsApp.supportedLocales].
///
/// See also:
///
/// * [LocaleResolutionCallback], which takes only one default locale (instead of a list)
/// and is attempted only after this callback fails or is null. [LocaleListResolutionCallback]
/// is recommended over [LocaleResolutionCallback].
typedef LocaleListResolutionCallback = Locale Function(List<Locale> locales, Iterable<Locale> supportedLocales);
/// The signature of [WidgetsApp.localeResolutionCallback].
///
/// A `LocaleResolutionCallback` is responsible for computing the locale of the app's
/// It is recommended to provide a [LocaleListResolutionCallback] instead of a
/// [LocaleResolutionCallback] when possible, as [LocaleListResolutionCallback] as
/// this callback only recieves a subset of the information provided
/// in [LocaleListResolutionCallback].
///
/// A [LocaleResolutionCallback] is responsible for computing the locale of the app's
/// [Localizations] object when the app starts and when user changes the default
/// locale for the device.
/// locale for the device after [LocaleListResolutionCallback] fails or is not provided.
///
/// This callback is also used if the app is created with a specific locale using
/// the [new WidgetsApp] `locale` parameter.
///
/// The `locale` is either the value of [WidgetsApp.locale], or the device's
/// locale when the app started, or the device locale the user selected after
/// the app was started. The `supportedLocales` parameter is the value of
/// The [locale] is either the value of [WidgetsApp.locale], or the device's default
/// locale when the app started, or the device locale the user selected after the app
/// was started. The default locale is the first locale in the list of preferred
/// locales. If [locale] is null, then Flutter has not yet recieved the locale
/// information from the platform. The [supportedLocales] parameter is just the value of
/// [WidgetsApp.supportedLocales].
///
/// See also:
///
/// * [LocaleListResolutionCallback], which takes a list of preferred locales (instead of one locale).
/// Resolutions by [LocaleListResolutionCallback] take precedence over [LocaleResolutionCallback].
typedef LocaleResolutionCallback = Locale Function(Locale locale, Iterable<Locale> supportedLocales);
/// The signature of [WidgetsApp.onGenerateTitle].
@ -124,6 +156,7 @@ class WidgetsApp extends StatefulWidget {
@required this.color,
this.locale,
this.localizationsDelegates,
this.localeListResolutionCallback,
this.localeResolutionCallback,
this.supportedLocales = const <Locale>[Locale('en', 'US')],
this.showPerformanceOverlay = false,
@ -468,29 +501,49 @@ class WidgetsApp extends StatefulWidget {
/// {@endtemplate}
final Iterable<LocalizationsDelegate<dynamic>> localizationsDelegates;
/// {@template flutter.widgets.widgetsApp.localeResolutionCallback}
/// {@template flutter.widgets.widgetsApp.localeListResolutionCallback}
/// This callback is responsible for choosing the app's locale
/// when the app is started, and when the user changes the
/// device's locale.
///
/// The returned value becomes the locale of this app's [Localizations]
/// widget. The callback's `locale` parameter is the device's locale when
/// the app started, or the device locale the user selected after the app was
/// started. The callback's `supportedLocales` parameter is just the value
/// [supportedLocales].
/// When a [localeListResolutionCallback] is provided, Flutter will first attempt to
/// resolve the locale with the provided [localeListResolutionCallback]. If the
/// callback or result is null, it will fallback to trying the [localeResolutionCallback].
/// If both [localeResolutionCallback] and [localeListResolutionCallback] are left null
/// or fail to resolve (return null), the [WidgetsApp.basicLocaleListResolution]
/// fallback algorithm will be used.
///
/// If the callback is null or if it returns null then the resolved locale is:
/// The priority of each available fallback is:
///
/// - The callback's `locale` parameter if it's equal to a supported locale.
/// - The first supported locale with the same [Locale.languageCode] as the
/// callback's `locale` parameter.
/// - The first locale in [supportedLocales].
/// 1. [localeListResolutionCallback] is attempted first.
/// 2. [localeResolutionCallback] is attempted second.
/// 3. Flutter's [WidgetsApp.basicLocaleListResolution] algorithm is attempted last.
/// {@endtemplate}
///
/// This callback considers the entire list of preferred locales.
///
/// This algorithm should be able to handle a null or empty list of preferred locales,
/// which indicates Flutter has not yet recieved locale information from the platform.
///
/// See also:
///
/// * [MaterialApp.localeResolutionCallback], which sets the callback of the
/// [WidgetsApp] it creates.
final LocaleListResolutionCallback localeListResolutionCallback;
/// {@macro flutter.widgets.widgetsApp.localeListResolutionCallback}
///
/// This callback considers only the default locale, which is the first locale
/// in the preferred locales list. It is preferred to set [localeListResolutionCallback]
/// over [localeResolutionCallback] as it provides the full preferred locales list.
///
/// This algorithm should be able to handle a null locale, which indicates
/// Flutter has not yet recieved locale information from the platform.
///
/// See also:
///
/// * [MaterialApp.localeListResolutionCallback], which sets the callback of the
/// [WidgetsApp] it creates.
final LocaleResolutionCallback localeResolutionCallback;
/// {@template flutter.widgets.widgetsApp.supportedLocales}
@ -607,7 +660,7 @@ class _WidgetsAppState extends State<WidgetsApp> implements WidgetsBindingObserv
void initState() {
super.initState();
_updateNavigator();
_locale = _resolveLocale(ui.window.locale, widget.supportedLocales);
_locale = _resolveLocales(ui.window.locales, widget.supportedLocales);
WidgetsBinding.instance.addObserver(this);
}
@ -717,35 +770,147 @@ class _WidgetsAppState extends State<WidgetsApp> implements WidgetsBindingObserv
// LOCALIZATION
/// This is the resolved locale, and is one of the supportedLocales.
Locale _locale;
Locale _resolveLocale(Locale newLocale, Iterable<Locale> supportedLocales) {
if (widget.localeResolutionCallback != null) {
final Locale locale = widget.localeResolutionCallback(newLocale, widget.supportedLocales);
Locale _resolveLocales(List<Locale> preferredLocales, Iterable<Locale> supportedLocales) {
// Attempt to use localeListResolutionCallback.
if (widget.localeListResolutionCallback != null) {
final Locale locale = widget.localeListResolutionCallback(preferredLocales, widget.supportedLocales);
if (locale != null)
return locale;
}
// newLocale can be null when called before the platform has had a chance to
// initialize the locales. We default to the first supported locale.
if (newLocale == null) {
// localeListResolutionCallback failed, falling back to localeResolutionCallback.
if (widget.localeResolutionCallback != null) {
final Locale locale = widget.localeResolutionCallback(preferredLocales.first, widget.supportedLocales);
if (locale != null)
return locale;
}
// Both callbacks failed, falling back to default algorithm.
return basicLocaleListResolution(preferredLocales, supportedLocales);
}
/// The default locale resolution algorithm.
///
/// Custom resolution algorithms can be provided through [WidgetsApp.localeListResolutionCallback]
/// or [WidgetsApp.localeResolutionCallback].
///
/// When no custom locale resolition algorithms are provided or if both fail to resolve,
/// Flutter will default to calling this algorithm.
///
/// This algorithm prioritizes speed at the cost of slightly less appropriate
/// resolutions for edge cases.
///
/// This algorithm will resolve to the earliest locale in [preferredLocales] that
/// matches the most fields, prioritizing in the order of perfect match,
/// languageCode+countryCode, languageCode+scriptCode, languageCode-only.
///
/// In the case where a locale is matched by languageCode-only and is not the
/// default (first) locale, the next locale in preferredLocales with a
/// perfect match can supercede the languageCode-only match if it exists.
///
/// When a preferredLocale matches more than one supported locale, it will resolve
/// to the first matching locale listed in the supportedLocales.
///
/// When all [preferredLocales] have been exhausted without a match, the first countryCode only
/// match will be returned.
///
/// When no match at all is found, the first (default) locale in [supportedLocales] will be
/// returned.
///
/// This algorithm does not take language distance (how similar languages are to each other)
/// into account, and will not handle edge cases such as resolving `de` to `fr` rather than `zh`
/// when `de` is not supported and `zh` is listed before `fr` (German is closer to French
/// than Chinese).
static Locale basicLocaleListResolution(List<Locale> preferredLocales, Iterable<Locale> supportedLocales) {
// preferredLocales can be null when called before the platform has had a chance to
// initialize the locales. Platforms without locale passing support will provide an empty list.
// We default to the first supported locale in these cases.
if (preferredLocales == null || preferredLocales.isEmpty) {
return supportedLocales.first;
}
Locale matchesLanguageCode;
// Hash the supported locales because apps can support many locales and would
// be expensive to search through them many times.
final Map<String, Locale> allSupportedLocales = HashMap<String, Locale>();
final Map<String, Locale> languageAndCountryLocales = HashMap<String, Locale>();
final Map<String, Locale> languageAndScriptLocales = HashMap<String, Locale>();
final Map<String, Locale> languageLocales = HashMap<String, Locale>();
final Map<String, Locale> countryLocales = HashMap<String, Locale>();
for (Locale locale in supportedLocales) {
if (locale == newLocale)
return newLocale;
if (locale.languageCode == newLocale.languageCode)
matchesLanguageCode ??= locale;
allSupportedLocales['${locale.languageCode}_${locale.scriptCode}_${locale.countryCode}'] ??= locale;
languageAndScriptLocales['${locale.languageCode}_${locale.scriptCode}'] ??= locale;
languageAndCountryLocales['${locale.languageCode}_${locale.countryCode}'] ??= locale;
languageLocales[locale.languageCode] ??= locale;
countryLocales[locale.countryCode] ??= locale;
}
return matchesLanguageCode ?? supportedLocales.first;
// Since languageCode-only matches are possibly low quality, we don't return
// it instantly when we find such a match. We check to see if the next
// preferred locale in the list has a high accuracy match, and only return
// the languageCode-only match when a higher accuracy match in the next
// preferred locale cannot be found.
Locale matchesLanguageCode;
Locale matchesCountryCode;
// Loop over user's preferred locales
for (int localeIndex = 0; localeIndex < preferredLocales.length; localeIndex += 1) {
final Locale userLocale = preferredLocales[localeIndex];
// Look for perfect match.
if (allSupportedLocales.containsKey('${userLocale.languageCode}_${userLocale.scriptCode}_${userLocale.countryCode}')) {
return userLocale;
}
// Look for language+script match.
if (userLocale.scriptCode != null) {
final Locale match = languageAndScriptLocales['${userLocale.languageCode}_${userLocale.scriptCode}'];
if (match != null) {
return match;
}
}
// Look for language+country match.
if (userLocale.countryCode != null) {
final Locale match = languageAndCountryLocales['${userLocale.languageCode}_${userLocale.countryCode}'];
if (match != null) {
return match;
}
}
// If there was a languageCode-only match in the previous iteration's higher
// ranked preferred locale, we return it if the current userLocale does not
// have a better match.
if (matchesLanguageCode != null) {
return matchesLanguageCode;
}
// Look and store language-only match.
Locale match = languageLocales[userLocale.languageCode];
if (match != null) {
matchesLanguageCode = match;
// Since first (default) locale is usually highly preferred, we will allow
// a languageCode-only match to be instantly matched. If the next preferred
// languageCode is the same, we defer hastily returning until the next iteration
// since at worst it is the same and at best an improved match.
if (localeIndex == 0 &&
!(localeIndex + 1 < preferredLocales.length && preferredLocales[localeIndex + 1].languageCode == userLocale.languageCode)) {
return matchesLanguageCode;
}
}
// countryCode-only match. When all else except default supported locale fails,
// attempt to match by country only, as a user is likely to be familar with a
// language from their listed country.
if (matchesCountryCode == null && userLocale.countryCode != null) {
match = countryLocales[userLocale.countryCode];
if (match != null) {
matchesCountryCode = match;
}
}
}
// When there is no languageCode-only match. Fallback to matching countryCode only. Country
// fallback only applies on iOS. When there is no countryCode-only match, we return first
// suported locale.
final Locale resolvedLocale = matchesLanguageCode ?? matchesCountryCode ?? supportedLocales.first;
return resolvedLocale;
}
@override
void didChangeLocale(Locale locale) {
if (locale == _locale)
return;
final Locale newLocale = _resolveLocale(locale, widget.supportedLocales);
void didChangeLocales(List<Locale> locales) {
final Locale newLocale = _resolveLocales(locales, widget.supportedLocales);
if (newLocale != _locale) {
setState(() {
_locale = newLocale;
@ -950,7 +1115,7 @@ class _WidgetsAppState extends State<WidgetsApp> implements WidgetsBindingObserv
}
final Locale appLocale = widget.locale != null
? _resolveLocale(widget.locale, widget.supportedLocales)
? _resolveLocales(<Locale>[widget.locale], widget.supportedLocales)
: _locale;
assert(_debugCheckLocalizations(appLocale));

12
packages/flutter/lib/src/widgets/binding.dart
View File

@ -219,7 +219,7 @@ abstract class WidgetsBindingObserver {
/// settings.
///
/// This method exposes notifications from [Window.onLocaleChanged].
void didChangeLocale(Locale locale) { }
void didChangeLocales(List<Locale> locale) { }
/// Called when the system puts the app in the background or returns
/// the app to the foreground.
@ -413,20 +413,20 @@ mixin WidgetsBinding on BindingBase, SchedulerBinding, GestureBinding, RendererB
@protected
@mustCallSuper
void handleLocaleChanged() {
dispatchLocaleChanged(ui.window.locale);
dispatchLocalesChanged(ui.window.locales);
}
/// Notify all the observers that the locale has changed (using
/// [WidgetsBindingObserver.didChangeLocale]), giving them the
/// `locale` argument.
/// [WidgetsBindingObserver.didChangeLocales]), giving them the
/// `locales` argument.
///
/// This is called by [handleLocaleChanged] when the [Window.onLocaleChanged]
/// notification is received.
@protected
@mustCallSuper
void dispatchLocaleChanged(Locale locale) {
void dispatchLocalesChanged(List<Locale> locales) {
for (WidgetsBindingObserver observer in _observers)
observer.didChangeLocale(locale);
observer.didChangeLocales(locales);
}
/// Notify all the observers that the active set of [AccessibilityFeatures]

669
packages/flutter_localizations/test/widgets_test.dart
View File

@ -745,4 +745,673 @@ void main() {
await tester.pumpAndSettle();
expect(find.text('zh_CN'), findsOneWidget);
});
// Example from http://unicode.org/reports/tr35/#LanguageMatching
testWidgets('WidgetsApp Unicode tr35 1', (WidgetTester tester) async {
await tester.pumpWidget(
buildFrame(
supportedLocales: const <Locale>[
Locale('de'),
Locale('fr'),
Locale('ja'),
],
buildContent: (BuildContext context) {
final Locale locale = Localizations.localeOf(context);
return Text('$locale');
}
)
);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'de', countryCode: 'AT'),
Locale.fromSubtags(languageCode: 'fr'),]
);
await tester.pumpAndSettle();
expect(find.text('de'), findsOneWidget);
});
// Examples from http://unicode.org/reports/tr35/#LanguageMatching
testWidgets('WidgetsApp Unicode tr35 2', (WidgetTester tester) async {
await tester.pumpWidget(
buildFrame(
supportedLocales: const <Locale>[
Locale('ja', 'JP'),
Locale('de'),
Locale('zh', 'TW'),
],
buildContent: (BuildContext context) {
final Locale locale = Localizations.localeOf(context);
return Text('$locale');
}
)
);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_TW'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'US'),
Locale.fromSubtags(languageCode: 'de'),
Locale.fromSubtags(languageCode: 'fr'),
Locale.fromSubtags(languageCode: 'de', countryCode: 'SW'),
Locale.fromSubtags(languageCode: 'it'),]
);
await tester.pumpAndSettle();
expect(find.text('de'), findsOneWidget);
});
testWidgets('WidgetsApp EdgeCase Chinese', (WidgetTester tester) async {
await tester.pumpWidget(
buildFrame(
supportedLocales: const <Locale>[
Locale.fromSubtags(languageCode: 'zh'),
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hans', countryCode: 'CN'),
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hant', countryCode: 'TW'),
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hant', countryCode: 'HK'),
],
buildContent: (BuildContext context) {
final Locale locale = Localizations.localeOf(context);
return Text('$locale');
}
)
);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'US'),
Locale.fromSubtags(languageCode: 'de'),
Locale.fromSubtags(languageCode: 'fr'),
Locale.fromSubtags(languageCode: 'de', countryCode: 'SW'),
Locale.fromSubtags(languageCode: 'zh'),]
);
await tester.pumpAndSettle();
expect(find.text('zh'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hant', countryCode: 'US'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_TW'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hant'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_TW'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hant', countryCode: 'TW'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_TW'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', countryCode: 'TW'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_TW'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', countryCode: 'HK'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_HK'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hans', countryCode: 'HK'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hans_CN'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', countryCode: 'CN'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hans_CN'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'US'),]
);
await tester.pumpAndSettle();
expect(find.text('zh'), findsOneWidget);
// This behavior is up to the implementer to decide if a perfect scriptCode match
// is better than a countryCode match.
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hant', countryCode: 'CN'),
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hans', countryCode: 'CN'),
Locale.fromSubtags(languageCode: 'zh', countryCode: 'CN'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_TW'), findsOneWidget);
// languageCode only match is not enough to prevent resolving a perfect match
// further down the preferredLocales list.
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'US'),
Locale.fromSubtags(languageCode: 'zh', countryCode: 'US'),
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hans', countryCode: 'CN'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hans_CN'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'US'),
Locale.fromSubtags(languageCode: 'zh', countryCode: 'US'),
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hans', countryCode: 'JP'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hans_CN'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', countryCode: 'US'),
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hans', countryCode: 'CN'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hans_CN'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'US'),
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hans', countryCode: 'CN'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hans_CN'), findsOneWidget);
// When no language match, we try for country only, since it is likely users are
// at least familiar with their country's language. This is a possible case only
// on iOS, where countryCode can be selected independently from language and script.
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', scriptCode: 'Hans', countryCode: 'TW'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_TW'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'TW'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_TW'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'HK'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_HK'), findsOneWidget);
});
// Same as 'WidgetsApp EdgeCase Chinese' test except the supportedLocales order is
// reversed.
testWidgets('WidgetsApp EdgeCase ReverseChinese', (WidgetTester tester) async {
await tester.pumpWidget(
buildFrame(
supportedLocales: const <Locale>[
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hant', countryCode: 'HK'),
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hant', countryCode: 'TW'),
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hans', countryCode: 'CN'),
Locale.fromSubtags(languageCode: 'zh'),
],
buildContent: (BuildContext context) {
final Locale locale = Localizations.localeOf(context);
return Text('$locale');
}
)
);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'US'),
Locale.fromSubtags(languageCode: 'de'),
Locale.fromSubtags(languageCode: 'fr'),
Locale.fromSubtags(languageCode: 'de', countryCode: 'SW'),
Locale.fromSubtags(languageCode: 'zh'),]
);
await tester.pumpAndSettle();
expect(find.text('zh'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hant', countryCode: 'US'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_HK'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hant'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_HK'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hant', countryCode: 'TW'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_TW'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', countryCode: 'TW'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_TW'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', countryCode: 'HK'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_HK'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hans', countryCode: 'HK'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hans_CN'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', countryCode: 'CN'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hans_CN'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'US'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_HK'), findsOneWidget);
// This behavior is up to the implementer to decide if a perfect scriptCode match
// is better than a countryCode match.
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hant', countryCode: 'CN'),
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hans', countryCode: 'CN'),
Locale.fromSubtags(languageCode: 'zh', countryCode: 'CN'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_HK'), findsOneWidget);
// languageCode only match is not enough to prevent resolving a perfect match
// further down the preferredLocales list.
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'US'),
Locale.fromSubtags(languageCode: 'zh', countryCode: 'US'),
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hans', countryCode: 'CN'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hans_CN'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'US'),
Locale.fromSubtags(languageCode: 'zh', countryCode: 'US'),
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hans', countryCode: 'JP'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hans_CN'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'zh', countryCode: 'US'),
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hans', countryCode: 'CN'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hans_CN'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'US'),
Locale.fromSubtags(languageCode: 'zh', scriptCode: 'Hans', countryCode: 'CN'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hans_CN'), findsOneWidget);
// When no language match, we try for country only, since it is likely users are
// at least familiar with their country's language. This is a possible case only
// on iOS, where countryCode can be selected independently from language and script.
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', scriptCode: 'Hans', countryCode: 'TW'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_TW'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'TW'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_TW'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'HK'),]
);
await tester.pumpAndSettle();
expect(find.text('zh_Hant_HK'), findsOneWidget);
});
// Examples from https://developer.android.com/guide/topics/resources/multilingual-support
testWidgets('WidgetsApp Android', (WidgetTester tester) async {
await tester.pumpWidget(
buildFrame(
supportedLocales: const <Locale>[
Locale('en'),
Locale('de', 'DE'),
Locale('es', 'ES'),
Locale('fr', 'FR'),
Locale('it', 'IT'),
],
buildContent: (BuildContext context) {
final Locale locale = Localizations.localeOf(context);
return Text('$locale');
}
)
);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'fr', countryCode: 'CH'),]
);
await tester.pumpAndSettle();
expect(find.text('fr_FR'), findsOneWidget);
});
// Examples from https://developer.android.com/guide/topics/resources/multilingual-support
testWidgets('WidgetsApp Android', (WidgetTester tester) async {
await tester.pumpWidget(
buildFrame(
supportedLocales: const <Locale>[
Locale('en'),
Locale('de', 'DE'),
Locale('es', 'ES'),
Locale('it', 'IT'),
],
buildContent: (BuildContext context) {
final Locale locale = Localizations.localeOf(context);
return Text('$locale');
}
)
);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'fr', countryCode: 'CH'),
Locale.fromSubtags(languageCode: 'it', countryCode: 'CH'),]
);
await tester.pumpAndSettle();
expect(find.text('it_IT'), findsOneWidget);
});
testWidgets('WidgetsApp Country-only fallback', (WidgetTester tester) async {
await tester.pumpWidget(
buildFrame(
supportedLocales: const <Locale>[
Locale('en', 'US'),
Locale('de', 'DE'),
Locale('de', 'AU'),
Locale('de', 'LU'),
Locale('de', 'CH'),
Locale('es', 'ES'),
Locale('es', 'US'),
Locale('it', 'IT'),
Locale('zh', 'CN'),
Locale('zh', 'TW'),
Locale('fr', 'FR'),
Locale('br', 'FR'),
Locale('pt', 'BR'),
Locale('pt', 'PT'),
],
buildContent: (BuildContext context) {
final Locale locale = Localizations.localeOf(context);
return Text('$locale');
}
)
);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'ar', countryCode: 'CH'),]
);
await tester.pumpAndSettle();
expect(find.text('de_CH'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'ar', countryCode: 'FR'),]
);
await tester.pumpAndSettle();
expect(find.text('fr_FR'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'ar', countryCode: 'US'),]
);
await tester.pumpAndSettle();
expect(find.text('en_US'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'es', countryCode: 'US'),]
);
await tester.pumpAndSettle();
expect(find.text('es_US'), findsOneWidget);
// Strongly prefer matching first locale even if next one is perfect.
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'pt'),
Locale.fromSubtags(languageCode: 'pt', countryCode: 'PT'),]
);
await tester.pumpAndSettle();
expect(find.text('pt_PT'), findsOneWidget);
// Don't country match with any other available match. This behavior is
// up for reconsideration.
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'ar', countryCode: 'BR'),
Locale.fromSubtags(languageCode: 'pt'),]
);
await tester.pumpAndSettle();
expect(find.text('pt_BR'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'ar', countryCode: 'BR'),
Locale.fromSubtags(languageCode: 'pt', countryCode: 'PT'),]
);
await tester.pumpAndSettle();
expect(find.text('pt_PT'), findsOneWidget);
});
// Simulates a Chinese-default app that supports english in Canada but not
// French. French-Canadian users should get 'en_CA' instead of Chinese.
testWidgets('WidgetsApp Multilingual country', (WidgetTester tester) async {
await tester.pumpWidget(
buildFrame(
supportedLocales: const <Locale>[
Locale('zh', 'CN'),
Locale('en', 'CA'),
Locale('en', 'US'),
Locale('en', 'AU'),
Locale('de', 'DE'),
],
buildContent: (BuildContext context) {
final Locale locale = Localizations.localeOf(context);
return Text('$locale');
}
)
);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'fr', countryCode: 'CA'),
Locale.fromSubtags(languageCode: 'fr'),]
);
await tester.pumpAndSettle();
expect(find.text('en_CA'), findsOneWidget);
});
testWidgets('WidgetsApp Common cases', (WidgetTester tester) async {
await tester.pumpWidget(
buildFrame(
// Decently well localized app.
supportedLocales: const <Locale>[
Locale('en', 'US'),
Locale('en', 'GB'),
Locale('en', 'AU'),
Locale('en', 'CA'),
Locale('zh', 'CN'),
Locale('zh', 'TW'),
Locale('de', 'DE'),
Locale('de', 'CH'),
Locale('es', 'MX'),
Locale('es', 'ES'),
Locale('es', 'AR'),
Locale('es', 'CO'),
Locale('ru', 'RU'),
Locale('fr', 'FR'),
Locale('fr', 'CA'),
Locale('ar', 'SA'),
Locale('ar', 'EG'),
Locale('ar', 'IQ'),
Locale('ar', 'MA'),
Locale('af'),
Locale('bg'),
Locale('nl', 'NL'),
Locale('pl'),
Locale('cs'),
Locale('fa'),
Locale('el'),
Locale('he'),
Locale('hi'),
Locale('pa'),
Locale('ta'),
Locale('id'),
Locale('it', 'IT'),
Locale('ja'),
Locale('ko'),
Locale('ms'),
Locale('mn'),
Locale('pt', 'BR'),
Locale('pt', 'PT'),
Locale('sv', 'SE'),
Locale('th'),
Locale('tr'),
Locale('vi'),
],
buildContent: (BuildContext context) {
final Locale locale = Localizations.localeOf(context);
return Text('$locale');
}
)
);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'US'),]
);
await tester.pumpAndSettle();
expect(find.text('en_US'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en'),]
);
await tester.pumpAndSettle();
expect(find.text('en_US'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'CA'),]
);
await tester.pumpAndSettle();
expect(find.text('en_CA'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'AU'),]
);
await tester.pumpAndSettle();
expect(find.text('en_AU'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'ar', countryCode: 'CH'),]
);
await tester.pumpAndSettle();
expect(find.text('ar_SA'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'ar'),]
);
await tester.pumpAndSettle();
expect(find.text('ar_SA'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'ar', countryCode: 'IQ'),]
);
await tester.pumpAndSettle();
expect(find.text('ar_IQ'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'es', countryCode: 'ES'),]
);
await tester.pumpAndSettle();
expect(find.text('es_ES'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'es'),]
);
await tester.pumpAndSettle();
expect(find.text('es_MX'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'pa', countryCode: 'US'),]
);
await tester.pumpAndSettle();
expect(find.text('pa'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'hi', countryCode: 'IN'),]
);
await tester.pumpAndSettle();
expect(find.text('hi'), findsOneWidget);
// Multiple preferred locales:
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'NZ'),
Locale.fromSubtags(languageCode: 'en', countryCode: 'AU'),
Locale.fromSubtags(languageCode: 'en', countryCode: 'GB'),
Locale.fromSubtags(languageCode: 'en'),]
);
await tester.pumpAndSettle();
expect(find.text('en_AU'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'ab'),
Locale.fromSubtags(languageCode: 'en', countryCode: 'NZ'),
Locale.fromSubtags(languageCode: 'en', countryCode: 'AU'),
Locale.fromSubtags(languageCode: 'en', countryCode: 'GB'),
Locale.fromSubtags(languageCode: 'en'),]
);
await tester.pumpAndSettle();
expect(find.text('en_AU'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'NZ'),
Locale.fromSubtags(languageCode: 'en', countryCode: 'PH'),
Locale.fromSubtags(languageCode: 'en', countryCode: 'ZA'),
Locale.fromSubtags(languageCode: 'en', countryCode: 'CB'),]
);
await tester.pumpAndSettle();
expect(find.text('en_US'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'en', countryCode: 'CA'),
Locale.fromSubtags(languageCode: 'en', countryCode: 'AU'),
Locale.fromSubtags(languageCode: 'en', countryCode: 'GB'),
Locale.fromSubtags(languageCode: 'en', countryCode: 'US'),]
);
await tester.pumpAndSettle();
expect(find.text('en_CA'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'da'),
Locale.fromSubtags(languageCode: 'en'),
Locale.fromSubtags(languageCode: 'en', countryCode: 'CA'),]
);
await tester.pumpAndSettle();
expect(find.text('en_CA'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'da'),
Locale.fromSubtags(languageCode: 'fo'),
Locale.fromSubtags(languageCode: 'hr'),]
);
await tester.pumpAndSettle();
expect(find.text('en_US'), findsOneWidget);
await tester.binding.setLocales(const <Locale>[
Locale.fromSubtags(languageCode: 'da'),
Locale.fromSubtags(languageCode: 'fo'),
Locale.fromSubtags(languageCode: 'hr', countryCode: 'CA'),]
);
await tester.pumpAndSettle();
expect(find.text('en_CA'), findsOneWidget);
});
}

18
packages/flutter_test/lib/src/binding.dart
View File

@ -225,13 +225,25 @@ abstract class TestWidgetsFlutterBinding extends BindingBase
Duration additionalTime = const Duration(milliseconds: 250),
});
/// Artificially calls dispatchLocaleChanged on the Widget binding,
/// Artificially calls dispatchLocalesChanged on the Widget binding,
/// then flushes microtasks.
///
/// Passes only one single Locale. Use [setLocales] to pass a full preferred
/// locales list.
Future<void> setLocale(String languageCode, String countryCode) {
return TestAsyncUtils.guard<void>(() async {
assert(inTest);
final Locale locale = Locale(languageCode, countryCode);
dispatchLocaleChanged(locale);
final Locale locale = Locale(languageCode, countryCode == '' ? null : countryCode);
dispatchLocalesChanged(<Locale>[locale]);
});
}
/// Artificially calls dispatchLocalesChanged on the Widget binding,
/// then flushes microtasks.
Future<void> setLocales(List<Locale> locales) {
return TestAsyncUtils.guard<void>(() async {
assert(inTest);
dispatchLocalesChanged(locales);
});
}