How to fix this exception:Cannot convert a NSColorType.Catalog color without specifying the color space, use the overload to specify an NSColorSpace

Question

I am trying to build a Xamarin.Forms 5 MacOS project - the XAML is the basic as provided by the default boiler plate code.

When I compile the project I get an exception:

The exception:

Cannot convert a NSColorType.Catalog color without specifying the color space, use the overload to specify an NSColorSpace

As I said, I have not added any custom code yet. How do I fix this?

Update

If I downgrade to Xamarin Form 4.8 it builds and runs with no exception:

So why is 5.x failing?

---

XAML

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="VisitsRota.MainPage">

    <StackLayout>
        <Frame BackgroundColor="#2196F3" Padding="24" CornerRadius="0">
            <Label Text="Welcome to Xamarin.Forms!" HorizontalTextAlignment="Center" TextColor="White" FontSize="36"/>
        </Frame>
        <Label Text="Start developing now" FontSize="Title" Padding="30,10,30,10"/>
        <Label Text="Make changes to your XAML file and save to see your UI update in the running app with XAML Hot Reload. Give it a try!" FontSize="16" Padding="30,0,30,0"/>
        <Label FontSize="16" Padding="30,24,30,0">
            <Label.FormattedText>
                <FormattedString>
                    <FormattedString.Spans>
                        <Span Text="Learn more at "/>
                        <Span Text="https://aka.ms/xamarin-quickstart" FontAttributes="Bold"/>
                    </FormattedString.Spans>
                </FormattedString>
            </Label.FormattedText>
        </Label>
    </StackLayout>

</ContentPage>

AppDelegate

using AppKit;
using Foundation;
using VisitsRota;
using Xamarin.Forms;
using Xamarin.Forms.Platform.MacOS;

namespace VisitsRota.MacOS
{
    [Register("AppDelegate")]
    public class AppDelegate : FormsApplicationDelegate
    {
        NSWindow window;
        public AppDelegate()
        {
            var style = NSWindowStyle.Closable | NSWindowStyle.Resizable | NSWindowStyle.Titled;

            var rect = new CoreGraphics.CGRect(200, 1000, 1024, 768);
            window = new NSWindow(rect, style, NSBackingStore.Buffered, false);
            window.Title = "Visits Rota for Mac";
            window.TitleVisibility = NSWindowTitleVisibility.Hidden;
        }

        public override NSWindow MainWindow
        {
            get { return window; }
        }

        public override void DidFinishLaunching(NSNotification notification)
        {
            Forms.Init();
            LoadApplication(new App());
            base.DidFinishLaunching(notification);
        }
    }
}

The exception is on base.DidFinishLaunching(notification); I think.

Answer 1

Updating to latest Xamarin.Forms resolved this issue.