NebulaLauncher/Nebula.Launcher/App.axaml.cs

using System;
using System.Linq;
using Avalonia;
using Avalonia.Controls.ApplicationLifetimes;
using Avalonia.Data.Core.Plugins;
using Avalonia.Markup.Xaml;
using Microsoft.Extensions.DependencyInjection;
using Nebula.Launcher.Views;
using Nebula.Shared;

namespace Nebula.Launcher;

public class App : Application
{
    private IServiceProvider _serviceProvider = null!;

    public override void Initialize()
    {
        AvaloniaXamlLoader.Load(this);
    }

    public override void OnFrameworkInitializationCompleted()
    {
        var services = new ServiceCollection();
        services.AddAvaloniaServices();
        services.AddServices();
        services.AddViews();

        _serviceProvider = services.BuildServiceProvider();

        switch (ApplicationLifetime)
        {
            case IClassicDesktopStyleApplicationLifetime desktop:
                DisableAvaloniaDataAnnotationValidation();
                desktop.MainWindow = _serviceProvider.GetService<MainWindow>();
                break;
            case ISingleViewApplicationLifetime singleViewPlatform:
                singleViewPlatform.MainView = _serviceProvider.GetRequiredService<MainView>();
                break;
        }

        base.OnFrameworkInitializationCompleted();
    }

    private void DisableAvaloniaDataAnnotationValidation()
    {
        // Get an array of plugins to remove
        var dataValidationPluginsToRemove =
            BindingPlugins.DataValidators.OfType<DataAnnotationsValidationPlugin>().ToArray();

        // remove each entry found
        foreach (var plugin in dataValidationPluginsToRemove) BindingPlugins.DataValidators.Remove(plugin);
    }
}