How-To: Configure and Use Localization

Uno.Extensions.Localization uses the locale-specific resources from resw files placed in folders corresponding to the well-known language tag (eg en-US). By opting into localization, an implementation of IStringLocalizer is registered with your application's IServiceCollection.

Step-by-steps

Important

This guide assumes you used the template wizard or dotnet new unoapp to create your solution. If not, it is recommended that you follow the Creating an application with Uno.Extensions article for creating an application from the template.

1. Opt into localization

• Organize your application's localized resw resources into folders corresponding to a language tag

• Call the UseLocalization() method to register the implementation of IStringLocalizer with the DI container:

  protected override void OnLaunched(LaunchActivatedEventArgs args)
  {
      var appBuilder = this.CreateBuilder(args)
          .Configure(hostBuilder =>
          {
              hostBuilder.UseLocalization();
          });
      ...
  }
  

2. Use the localization service to resolve localized text

• Add a constructor parameter of IStringLocalizer type to a view model you registered with the service collection:

  public class MainViewModel
  {
      private readonly IStringLocalizer stringLocalizer;
  
      public MainViewModel(IStringLocalizer stringLocalizer)
      {
          this.stringLocalizer = stringLocalizer;
      }
  }
  

• You can then resolve the text either as a string or LocalizedString:

  // Using IStringLocalizer as a dictionary
  string myString = stringLocalizer["MyKey"];
  
  // You can get a LocalizedString object too
  LocalizedString myString = stringLocalizer["MyKey"];
  var isResourceNotFound = myString.ResourceNotFound;
  

3. Update the UI culture with LocalizationSettings

• Add a constructor parameter of ILocalizationService type to a view model you registered with the service collection:

  public class MainViewModel
  {
      private readonly ILocalizationService localizationService;
  
      public MainViewModel(ILocalizationService localizationService)
      {
          this.localizationService = localizationService;
      }
  }
  

• Toggle the UI culture using the injected service:

  public async Task ToggleLocalization()
  {
      var currentCulture = localizationService.CurrentCulture;
  
      var culture = localizationService.SupportedCultures.First(culture => culture.Name != currentCulture.Name);
      await localizationService.SetCurrentCultureAsync(culture);
  }
  

Tip

This action requires an app restart before you're able to observe the changes