Using standard dotnet IHost and CreateApplicationBuilder in Avalonia apps

[atrauzzi]

I'm wondering if anyone has explored adding support for the standard dotnet application IHost functionality to Avalonia applications.

You could think of it as being vaguely like having this in your App.axaml.cs:

public partial class App : Application
{
    private IHost? host;

    public override void OnFrameworkInitializationCompleted()
    {
        var builder = Host.CreateApplicationBuilder();

        // note: Lots of stuff or extension methods would go here.

        host = builder.Build();
            
        Task.Run(() => host.StartAsync());

        base.OnFrameworkInitializationCompleted();
    }

    // ...

Perhaps there's a better way that's already been explored, but the code example above is just to illustrate the premise. With this in place, it should in theory be easy to integrate with the rest of the dotnet library ecosystem. Particularly through DI and configuration. Maybe I should be managing the IHost from Program.cs instead?

But I'm wondering if there are any threading gotchas that might be important to anticipate in such an approach. Or when code running in the IHost thread needs to trigger things in the main Avalonia UI thread?

Interested in hearing more from anyone who has either done this or has insights! 🙏

[LaurentInSeattle]

I am using the standard .Net IHost in all my Avalonia apps mostly for dependency injection and singleton management.
No issues.

You may wish to take a look at:
https://github.com/LaurentInSeattle/Lyt.Avalonia.Framework/blob/main/Lyt.Avalonia.Mvvm/ApplicationBase.cs

HTH

[atrauzzi]

Do you do anything to ensure that the IHost runs on a different thread to the Avalonia UI?

[LaurentInSeattle]

No. And I don't understand why this could be important...