MVVMCross 即时更改语言 - IOS/Android

Question

我已经搜索了有关这些的网络和论坛 - 找到了这些：

https://forums.xamarin.com/discussion/103572/any-xamarin-ios-code-to-change-the-language-of-the-app-instantly-without-need-to-restart-the-app

http://enginecore.blogspot.in/2013/09/localization-in-xamarin-mvvmcross_18.html

http://opendix.blogspot.in/2013/05/using-resx-files-for-localization-in.html

还有更多适用于 Xamarin Forms 的内容。

但这些都不是有希望的，并且会即时更改文本（在内部更改文本）。

有人可以帮忙吗？

Answer 1

对于 Android，您可以这样做：

• 像这样创建自己的 contextWrapper：

   public class MyContextWrapper : ContextWrapper
  {
     public MyContextWrapper(Context context) : base(context)          
     {
  
     }
  public static Locale getSystemLocaleLegacy(Configuration config)
  {
      return config.Locale;
  }
  public static Locale getSystemLocale(Configuration config)
  {
      return config.Locales.Get(0);
  }
  public static void setSystemLocaleLegacy(Configuration config, Locale locale)
  {
      config.SetLocale(locale);
      config.SetLayoutDirection(locale);
  }
  public static void setSystemLocale(Configuration config, Locale locale)
  {
      config.SetLocale(locale);
      config.SetLayoutDirection(locale);
  }
  
  public static ContextWrapper wrap(Context context, string language)
  {
      Configuration config = context.Resources.Configuration;
      Locale sysLocale = null;
      if (Build.VERSION.SdkInt >= BuildVersionCodes.N)
      {
          sysLocale = getSystemLocale(config);
      }
      else
      {
          sysLocale = getSystemLocaleLegacy(config);
      }
  
      Locale locale;
  
      if (language == "en")
      {
          locale = new Locale(language, "US");
      }
      else if (language == "zh")
      {
          locale = new Locale(language, "CN");
      }
      else
      {
          locale = new Locale("en", "US");
      }
  
      Locale.Default = (locale);
  
      if (Build.VERSION.SdkInt >= BuildVersionCodes.N)
      {
          setSystemLocale(config, locale);
      }
      else
      {
          setSystemLocaleLegacy(config, locale);
      }
  
      if (Build.VERSION.SdkInt >= BuildVersionCodes.JellyBeanMr1)
      {
          context = context.CreateConfigurationContext(config);
      }
      else
      {
          context.Resources.UpdateConfiguration(config, context.Resources.DisplayMetrics);
      }
  
      return new MyContextWrapper(context);
  }
  

  }

• 将以下代码添加到您的活动中：

   protected override void AttachBaseContext(Context @base)
  {
      try
      {              
      base.AttachBaseContext(MyContextWrapper.wrap(@base,"Your_language"));
      }
  
  }
  

• 在资源中添加语言字符串文件及其相应的语言名称，例如对于中文，您添加以下值文件夹： values-zh-rCN

更多信息请查看here

更新：

• ios 代码：

    public class Localize
  {
     public void SetLocale(CultureInfo ci)
  {
      Thread.CurrentThread.CurrentCulture = ci;
      Thread.CurrentThread.CurrentUICulture = ci;
  
      CultureChanged?.Invoke(this, ci);
  }
  
  public event EventHandler<CultureInfo> CultureChanged = delegate { };
  
  public CultureInfo GetCurrentCultureInfo()
  {
      var netLanguage = "en";
      if (NSLocale.PreferredLanguages.Length > 0)
      {
          var pref = NSLocale.PreferredLanguages[0];
          netLanguage = iOSToDotnetLanguage(pref);
      }
      // this gets called a lot - try/catch can be expensive so consider caching or something
      System.Globalization.CultureInfo ci = null;
      try
      {
          ci = new System.Globalization.CultureInfo(netLanguage);
      }
      catch
      {
          // iOS locale not valid .NET culture (eg. "en-ES" : English in Spain)
          // fallback to first characters, in this case "en"
          try
          {
              var fallback = ToDotnetFallbackLanguage(new PlatformCulture(netLanguage));
              ci = new System.Globalization.CultureInfo(fallback);
          }
          catch
          {
              // iOS language not valid .NET culture, falling back to English
              ci = new System.Globalization.CultureInfo("en");
          }
      }
      return ci;
  }
  
  string iOSToDotnetLanguage(string iOSLanguage)
  {
      var netLanguage = iOSLanguage;
      //certain languages need to be converted to CultureInfo equivalent
      switch (iOSLanguage)
      {
          case "ms-MY": // "Malaysian (Malaysia)" not supported .NET culture
          case "ms-SG": // "Malaysian (Singapore)" not supported .NET culture
              netLanguage = "ms"; // closest supported
              break;
          case "gsw-CH": // "Schwiizertüütsch (Swiss German)" not supported .NET culture
              netLanguage = "de-CH"; // closest supported
              break;
              // add more application-specific cases here (if required)
              // ONLY use cultures that have been tested and known to work
      }
      return netLanguage;
  }
  
  string ToDotnetFallbackLanguage(PlatformCulture platCulture)
  {
      var netLanguage = platCulture.LanguageCode; // use the first part of the identifier (two chars, usually);
      switch (platCulture.LanguageCode)
      {
          case "pt":
              netLanguage = "pt-PT"; // fallback to Portuguese (Portugal)
              break;
          case "gsw":
              netLanguage = "de-CH"; // equivalent to German (Switzerland) for this app
              break;
              // add more application-specific cases here (if required)
              // ONLY use cultures that have been tested and known to work
      }
      return netLanguage;
  }
   }
  

  • 有关步骤的参考，请转到here

Answer 2

如果您使用 MvvmCross 和 resx PCL，则此代码适用于我

public class ResxTextProvider : IMvxTextProvider
    {
        private readonly ResourceManager _resourceManager;
        private readonly MvxSubscriptionToken _token;
        IMvxMessenger messenger;

        public ResxTextProvider(ResourceManager resourceManager , string CultureInfoString)
        {
            _resourceManager = resourceManager;
            CurrentLanguage = new CultureInfo(CultureInfoString);

            messenger = Mvx.Resolve<IMvxMessenger>();
            if (messenger != null)
            {
                _token = messenger.Subscribe<languageChangedMessage>(OnlanguageChange);
            }
        }

        private void OnlanguageChange(languageChangedMessage obj)
        {
            CurrentLanguage = new CultureInfo(obj.LangId);
        }