How-To: Enable and Use Logging

Uno.Extensions.Logging allows you to leverage logging capabilities tailored to your target platform to easily record events for XAML layout, Uno-internal messages, and custom events with severity and verbosity levels of your choice.

Step-by-step

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 documentation to create an application from the template.

1. Installation

• Add Logging to the <UnoFeatures> property in the Class Library (.csproj) file. If you already have Extensions in <UnoFeatures>, then Logging is already installed, as its dependencies are included with the Extensions feature.

  <UnoFeatures>
      Material;
  +   Logging;
      Toolkit;
      MVUX;
  </UnoFeatures>
  

2. Opt into logging

• Uno.Extensions offers a simple way to wire up platform-specific log providers such as Uno.Extensions.Logging.OSLogLoggerProvider for iOS and Uno.Extensions.Logging.WebAssembly.WebAssemblyConsoleLoggerProvider for WASM as both debug and console logging.

• Call the UseLogging() method to register the resultant implementation of ILogger with the DI container:

  protected override void OnLaunched(LaunchActivatedEventArgs e)
  {
      var appBuilder = this.CreateBuilder(args)
          .Configure(host => {
              host.UseLogging();
          });
  ...
  

3. Use the injected service to log application events

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

  public class MainViewModel
  {
      private readonly ILogger logger;
  
      public MainViewModel(ILogger logger)
      {
          this.logger = logger;
      }
      ...
  }
  

• You can now record application events using the injected ILogger service implementation:

  logger.LogInformation("This is an information log.");