.Net Maui Embedded Controls project won't build after .net9 upgrade

[trydalch]

We use Maui Control embedding. After upgrading our projects from .net8 to .net9, we get these nuget errors related to the Maui packages, and our uno project won't build.

1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605: Warning As Error: Detected package downgrade: Microsoft.Maui.Controls from 9.0.0 to 9.0.0-rc.2.24503.2. Reference the package directly from the project to select a different version. 
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605:  WereAllRelated.Uno -> WereAllRelated.Uno.MauiControls -> Microsoft.Maui.Controls (>= 9.0.0) 
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605:  WereAllRelated.Uno -> Microsoft.Maui.Controls (>= 9.0.0-rc.2.24503.2)
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605: Warning As Error: Detected package downgrade: Microsoft.Maui.Controls.Compatibility from 9.0.0 to 9.0.0-rc.2.24503.2. Reference the package directly from the project to select a different version. 
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605:  WereAllRelated.Uno -> WereAllRelated.Uno.MauiControls -> Microsoft.Maui.Controls.Compatibility (>= 9.0.0) 
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605:  WereAllRelated.Uno -> Microsoft.Maui.Controls.Compatibility (>= 9.0.0-rc.2.24503.2)
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605: Warning As Error: Detected package downgrade: Microsoft.Maui.Controls from 9.0.0 to 9.0.0-rc.2.24503.2. Reference the package directly from the project to select a different version. 
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605:  WereAllRelated.Uno -> WereAllRelated.Uno.MauiControls -> Microsoft.Maui.Controls (>= 9.0.0) 
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605:  WereAllRelated.Uno -> Microsoft.Maui.Controls (>= 9.0.0-rc.2.24503.2)
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605: Warning As Error: Detected package downgrade: Microsoft.Maui.Controls.Compatibility from 9.0.0 to 9.0.0-rc.2.24503.2. Reference the package directly from the project to select a different version. 
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605:  WereAllRelated.Uno -> WereAllRelated.Uno.MauiControls -> Microsoft.Maui.Controls.Compatibility (>= 9.0.0) 
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605:  WereAllRelated.Uno -> Microsoft.Maui.Controls.Compatibility (>= 9.0.0-rc.2.24503.2)
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605: Warning As Error: Detected package downgrade: Microsoft.Maui.Controls from 9.0.0 to 9.0.0-rc.2.24503.2. Reference the package directly from the project to select a different version. 
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605:  WereAllRelated.Uno -> WereAllRelated.Uno.MauiControls -> Microsoft.Maui.Controls (>= 9.0.0) 
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605:  WereAllRelated.Uno -> Microsoft.Maui.Controls (>= 9.0.0-rc.2.24503.2)
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605: Warning As Error: Detected package downgrade: Microsoft.Maui.Controls.Compatibility from 9.0.0 to 9.0.0-rc.2.24503.2. Reference the package directly from the project to select a different version. 
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605:  WereAllRelated.Uno -> WereAllRelated.Uno.MauiControls -> Microsoft.Maui.Controls.Compatibility (>= 9.0.0) 
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605:  WereAllRelated.Uno -> Microsoft.Maui.Controls.Compatibility (>= 9.0.0-rc.2.24503.2)
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605: Warning As Error: Detected package downgrade: Microsoft.Maui.Controls from 9.0.0 to 9.0.0-rc.2.24503.2. Reference the package directly from the project to select a different version. 
1>C:\Users\Trevor.Rydalch\source\repos\Z\OGF\Client.Uno\WereAllRelated.Uno\WereAllRelated.Uno\WereAllRelated.Uno.csproj : error NU1605:  WereAllRelated.Uno -> WereAllRelated.Uno.MauiControls -> Microsoft.Maui.Controls (>= 9.0.0) 

I've created a blank app using the wizard, targeting .net 9 and enabled MauiEmbedding, and I don't get these problems. I've compared the projects and nothing really stands out as an obvious cause of the problem.

[jeromelaban]

Thanks for the report. Can you tell which version of the uno.sdk you are using?

[trydalch]

Yes, using 5.5.49

[trydalch]

But I just upgraded to 5.6.22 and am now seeing if that resolved it.

[trydalch]

Upgrading to 5.6.22 seems to have resolved it.

[jeromelaban]

Thanks for the update!

[trydalch]

So the build errors were resolved, but now we're getting an interesting runtime error. The app crashes before the app even launches (barely shows the splash screen image).

I found this error in the device logs:

[trydalch]

The app still runs in debug mode.

[jeromelaban]

Thanks for the update. Unfortunately this is a .NET runtime error that uno cannot manage, and likely will require posting an issue directly on the https://github.com/dotnet/android repository.

Still, can you post the text of the error entirely here please?