How to use custom fonts via FontCollection?

[AVVI94]

Hello,

I recently tried to use custom fonts in my application but couldn't get them to work with the EmbeddedFontCollection. The only approach that worked was using StaticResource, which I wanted to avoid.

When I added fonts to the AppBuilder using ConfigureFonts, all my fonts were successfully parsed. However, when I tried to use them in a TextBlock's FontFamily, the fallback font family was always applied instead.

Is there a specific step I might be missing, or how can I make this work as expected?

My code:

Program.cs:

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()
        => AppBuilder.Configure<App>()
            .UsePlatformDetect()
            .WithInterFont() //tried with and without this line
            .ConfigureFonts(x =>
            {
                x.AddFontCollection(new FontCollection());
            })
            .LogToTrace();
}

class FontCollection : EmbeddedFontCollection
{
    public FontCollection()
        :base(new("fonts:SourceCodePro"),
                 new("avares://ICARA2/Assets/Fonts/SourceCode"))
    {
        
    }
}

[stevemonaco]

There's a lot of background in this discussion: #17199

In general, AFAIK, you can't use the family name directly, but need to use a specific font scheme when constructing a FontFamily.

[Gillibald]

FontFamily="fonts:SourceCodePro#Source Code Pro"