MyAvaloniaDemo/Program.cs

using Avalonia;
using Avalonia.Media;
using Avalonia.ReactiveUI;
using System;
using System.Runtime.InteropServices;

namespace MyAvaloniaApp;

class Program
{
    [STAThread]
    public static void Main(string[] args)
    {
        // 简化的启动方式，HostBuilder 配置已集成到 App 中
        BuildAvaloniaApp().StartWithClassicDesktopLifetime(args);
    }
    
    /// <summary>
    /// 构建 Avalonia 应用程序
    /// </summary>
    /// <returns>AppBuilder</returns>
    public static AppBuilder BuildAvaloniaApp()
    {
        var builder = AppBuilder.Configure<App>()
            .UsePlatformDetect()
            .LogToTrace()
            .UseReactiveUI();
            
        // Linux字体配置
        if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
        {
            // 在Linux上使用系统字体而不是Inter字体
            builder = builder.With(new FontManagerOptions
            {
                DefaultFamilyName = "DejaVu Sans, Liberation Sans, Arial, sans-serif"
            });
        }
        else
        {
            // Windows和macOS使用Inter字体
            builder = builder.WithInterFont();
        }
        
        return builder;
    }
}