Avalonia: FontWeight=Bold doesn't work on macOS

[ForNeVeR]

Write the following program and run on macOS:

using Avalonia;
using Avalonia.Controls;
using Avalonia.Logging.Serilog;
using Avalonia.Media;

namespace avaloniatest
{
    class Program
    {
        public static void Main(string[] args) => BuildAvaloniaApp().Start(AppMain, args);

        public static AppBuilder BuildAvaloniaApp()
            => AppBuilder.Configure<App>()
                .UsePlatformDetect()
                .LogToDebug()
                .UseReactiveUI();

        private static void AppMain(Application app, string[] args)
        {          
            var window = new Window() {Content = new TextBlock() {FontWeight = FontWeight.Bold, Text = "fooh"}};

            app.Run(window);
        }
    }
}

I expect that it will show a bold text, but the text in the TextBlock is rendered as normal. Works the same for TextBox.

[x2bool]

FontWeight=Bold does work if you explicitly specify a font family that provides bold font weight. I don't know if this is expected behavior though.

[Gillibald]

If your FontFamily doesn't have a Typeface with a weight of Bold the render pipeline uses the nearest match. Make sure your FontFamily contains a Bold face.

[ForNeVeR]

Should we maybe change the default font family on macOS, then? Or is it okay that the default font doesn't support bold?

[Gillibald]

The default is the System's default. If that font doesn't fulfill your needs just change it on your Window to share the FontFamily on all children controls.

[ForNeVeR]

According to the wiki, the default font on macOS should be Lucida Grande which should support bold.

[Gillibald]

And what happens if you specify that font explicitly? Does it render correctly? I can't debug this because I do not own a Mac and that will never change.

[x2bool]

Well, I totally agree with ForNeVeR. If FontFamily=Bold does not work on "Hello, World" app then it creates a wrong impression that it doesn't work at all. It took me a while to figure out why it does not make font bold with default typeface.

[x2bool]

BTW The primary system font in OS X El Capitan and above is San Francisco.

[ForNeVeR]

It works if I set FontFamily=FontFamily.Parse("Lucida Grande"), but I wasn't able to determine which is the default yet. FontFamily.Default returns a family with empty name in debugger.

Interestingly, FontFamily.SystemFontFamilies yields no font named "San Francisco" on my Mac, and even the Font Book list doesn't show it.

[Gillibald]

Will have a look shortly. Could be that the default lookup isn't working for the System's default

[Gillibald]

Should work when my fix is merged

[dtchepak]

This issue still exists on 0.9.0-preview3 when running the original example on Mojave (10.14.6).

I have the following styles in App.xaml:

<StyleInclude Source="avares://Avalonia.Themes.Default/DefaultTheme.xaml" />
<StyleInclude Source="avares://Avalonia.Themes.Default/Accents/BaseLight.xaml" />

Please let me know if there is any other information I can provide that would be helpful.

[Gillibald]

I can't reproduce this issue on Windows. Can't test on Mac. When I set FontWeight="Bold" on my window everything is rendered bold.

[dtchepak]

@Gillibald Yes it works fine on Windows.

[danwalmsley]

Control catalog on OSX 10.14.6 bold font working?

[Gillibald]

To repro this you have to set FontWeight to bold on the MainWindow

[Carlos487]

The problem persist in 0.9.9 release in Mojave 10.14.6. I created a blank project and followed the steps in the styles section of the docs. The size of the text changes but not the weight. How can I provide you with more debugging information?