Program.cs

using Avalonia;
using ReactiveUI.Avalonia;
using System;
using Projektanker.Icons.Avalonia;
using Projektanker.Icons.Avalonia.FontAwesome;
using Projektanker.Icons.Avalonia.MaterialDesign;

namespace CodeXUI.Avalonia;

sealed class Program
{
    // Initialization code. Don't use any Avalonia, third-party APIs or any
    // SynchronizationContext-reliant code before AppMain is called: things aren't initialized
    // yet and stuff might break.
    [STAThread]
    public static void Main(string[] args) => BuildAvaloniaApp()
        .StartWithClassicDesktopLifetime(args);

    // Avalonia configuration, don't remove; also used by visual designer.
    public static AppBuilder BuildAvaloniaApp()
    {
        IconProvider.Current
            .Register<FontAwesomeIconProvider>()
            .Register<MaterialDesignIconProvider>();
        return AppBuilder.Configure<App>()
            .UsePlatformDetect()
            .WithInterFont()
            .LogToTrace()
            .UseReactiveUI();
    }
}