io.flutter.plugin.localization.LocalizationPlugin Class Reference

Public Member Functions
	LocalizationPlugin ( @NonNull Context context, @NonNull LocalizationChannel localizationChannel)
Locale	resolveNativeLocale (@Nullable List< Locale > supportedLocales)
void	sendLocalesToFlutter (@NonNull Configuration config)

Static Public Member Functions
static Locale	localeFromString (@NonNull String localeString)

Package Attributes
final LocalizationChannel.LocalizationMessageHandler	localizationMessageHandler

Detailed Description

Android implementation of the localization plugin.

Definition at line 23 of file LocalizationPlugin.java.

Constructor & Destructor Documentation

LocalizationPlugin()

io.flutter.plugin.localization.LocalizationPlugin.LocalizationPlugin ( @NonNull Context  context, @NonNull LocalizationChannel  localizationChannel  )

inline

Definition at line 59 of file LocalizationPlugin.java.

                                                                                  {
 
    this.context = context;
    this.localizationChannel = localizationChannel;
    this.localizationChannel.setLocalizationMessageHandler(localizationMessageHandler);
  }

Member Function Documentation

localeFromString()

static Locale io.flutter.plugin.localization.LocalizationPlugin.localeFromString ( @NonNull String  localeString )

inlinestatic

Computes the Locale from the provided String with format language[-script][-region][-...], where script is an alphabet string of length 4, and region is either an alphabet string of length 2 or a digit string of length 3.

Definition at line 185 of file LocalizationPlugin.java.

                                                                      {
    // Normalize the locale string, replace all underscores with hyphens.
    localeString = localeString.replace('_', '-');
 
    // Pre-API 21, we fall back to manually parsing the locale tag.
    String parts[] = localeString.split("-", -1);
 
    // Assume the first part is always the language code.
    String languageCode = parts[0];
    String scriptCode = "";
    String countryCode = "";
    int index = 1;
    if (parts.length > index && parts[index].length() == 4) {
      scriptCode = parts[index];
      index++;
    }
    if (parts.length > index && parts[index].length() >= 2 && parts[index].length() <= 3) {
      countryCode = parts[index];
      index++;
    }
    // Ignore the rest of the locale for this purpose.
    return new Locale(languageCode, countryCode, scriptCode);
  }

resolveNativeLocale()

Locale io.flutter.plugin.localization.LocalizationPlugin.resolveNativeLocale ( @Nullable List< Locale >  supportedLocales )

inline

Computes the Locale in supportedLocales that best matches the user's preferred locales.

FlutterEngine must be non-null when this method is invoked.

Definition at line 74 of file LocalizationPlugin.java.

                                                                             {
    if (supportedLocales == null || supportedLocales.isEmpty()) {
      return null;
    }
 
    // Android improved the localization resolution algorithms after API 24 (7.0, Nougat).
    // See https://developer.android.com/guide/topics/resources/multilingual-support
    //
    // LanguageRange and Locale.lookup was added in API 26 and is the preferred way to
    // select a locale. Pre-API 26, we implement a manual locale resolution.
    if (Build.VERSION.SDK_INT >= API_LEVELS.API_26) {
      // Modern locale resolution using LanguageRange
      // https://developer.android.com/guide/topics/resources/multilingual-support#postN
      List<Locale.LanguageRange> languageRanges = new ArrayList<>();
      LocaleList localeList = context.getResources().getConfiguration().getLocales();
      int localeCount = localeList.size();
      for (int index = 0; index < localeCount; ++index) {
        Locale locale = localeList.get(index);
        // Convert locale string into language range format.
        String fullRange = locale.getLanguage();
        if (!locale.getScript().isEmpty()) {
          fullRange += "-" + locale.getScript();
        }
        if (!locale.getCountry().isEmpty()) {
          fullRange += "-" + locale.getCountry();
        }
        languageRanges.add(new Locale.LanguageRange(fullRange));
        languageRanges.add(new Locale.LanguageRange(locale.getLanguage()));
        languageRanges.add(new Locale.LanguageRange(locale.getLanguage() + "-*"));
      }
      Locale platformResolvedLocale = Locale.lookup(languageRanges, supportedLocales);
      if (platformResolvedLocale != null) {
        return platformResolvedLocale;
      }
      return supportedLocales.get(0);
    } else if (Build.VERSION.SDK_INT >= API_LEVELS.API_24) {
      // Modern locale resolution without languageRange
      // https://developer.android.com/guide/topics/resources/multilingual-support#postN
      LocaleList localeList = context.getResources().getConfiguration().getLocales();
      for (int index = 0; index < localeList.size(); ++index) {
        Locale preferredLocale = localeList.get(index);
        // Look for exact match.
        for (Locale locale : supportedLocales) {
          if (preferredLocale.equals(locale)) {
            return locale;
          }
        }
        // Look for exact language only match.
        for (Locale locale : supportedLocales) {
          if (preferredLocale.getLanguage().equals(locale.toLanguageTag())) {
            return locale;
          }
        }
        // Look for any locale with matching language.
        for (Locale locale : supportedLocales) {
          if (preferredLocale.getLanguage().equals(locale.getLanguage())) {
            return locale;
          }
        }
      }
      return supportedLocales.get(0);
    }
 
    // Legacy locale resolution
    // https://developer.android.com/guide/topics/resources/multilingual-support#preN
    Locale preferredLocale = context.getResources().getConfiguration().locale;
    if (preferredLocale != null) {
      // Look for exact match.
      for (Locale locale : supportedLocales) {
        if (preferredLocale.equals(locale)) {
          return locale;
        }
      }
      // Look for exact language only match.
      for (Locale locale : supportedLocales) {
        if (preferredLocale.getLanguage().equals(locale.toString())) {
          return locale;
        }
      }
    }
    return supportedLocales.get(0);
  }

sendLocalesToFlutter()

void io.flutter.plugin.localization.LocalizationPlugin.sendLocalesToFlutter ( @NonNull Configuration  config )

inline

Send the current Locale configuration to Flutter.

FlutterEngine must be non-null when this method is invoked.

Definition at line 163 of file LocalizationPlugin.java.

                                                                  {
    List<Locale> locales = new ArrayList<>();
    if (Build.VERSION.SDK_INT >= API_LEVELS.API_24) {
      LocaleList localeList = config.getLocales();
      int localeCount = localeList.size();
      for (int index = 0; index < localeCount; ++index) {
        Locale locale = localeList.get(index);
        locales.add(locale);
      }
    } else {
      locales.add(config.locale);
    }
 
    localizationChannel.sendLocales(locales);
  }

Member Data Documentation

localizationMessageHandler

final LocalizationChannel.LocalizationMessageHandler io.flutter.plugin.localization.LocalizationPlugin.localizationMessageHandler

package

Initial value:

=
      new LocalizationChannel.LocalizationMessageHandler() {
        @Override
        public String getStringResource(@NonNull String key, @Nullable String localeString) {
          Context localContext = context;
          String stringToReturn = null;
          Locale savedLocale = null;
 
          if (localeString != null) {
            Locale locale = localeFromString(localeString);
 
            Configuration config = new Configuration(context.getResources().getConfiguration());
            config.setLocale(locale);
            localContext = context.createConfigurationContext(config);
          }
 
          String packageName = context.getPackageName();
          int resId = localContext.getResources().getIdentifier(key, "string", packageName);
          if (resId != 0) {
            
            stringToReturn = localContext.getResources().getString(resId);
          }
 
          return stringToReturn;
        }
      }

Definition at line 32 of file LocalizationPlugin.java.

---

The documentation for this class was generated from the following file:

• shell/platform/android/io/flutter/plugin/localization/LocalizationPlugin.java