Building as an external library is confusing.

[AlexanderBlackman]

I've recently made some changes to my fork of DevWinUI, and they work in the sample app, but I want to test them in my own app.

Building the DevWinUI csproj in its original slnx works.
Adding it as an external library to another solution doesn't work. The build always fails.

What should I be doing differently? I have a reference to
<ProjectReference Include="..\..\DevWinUI\dev\DevWinUI\DevWinUI.csproj" />

[ghost1372]

Hi @AlexanderBlackman
I think this is related to the TargetFramework configuration.

Currently, we support net8, net9, and net10 targeting Windows 10 (19041). However, for faster debugging, I temporarily limited the Debug configuration to net10 only. In addition, our shader library only supports 22621+ and does not work with 19041.

Please check your TargetFramework. In the Debug configuration, it should be:

net10.0-windows10.0.22621.0

Also, whenever you switch between Debug and Release, make sure to:

1. Close Visual Studio.
2. Delete the bin and obj folders. (or just run our Clean-obj-bin.bat script)
3. Open Visual Studio
4. Rebuild the solution.

This is necessary because the Release configuration targets multiple frameworks, while Debug currently targets only a single framework.

For a simpler fix, you can edit Directory.Build.props and configure both Debug and Release to use a single target framework.

 <DebugTargetFramework>net10.0-windows10.0.19041.0</DebugTargetFramework>
 <DebugShaderAndGalleryTargetFramework>net10.0-windows10.0.26100.0</DebugShaderAndGalleryTargetFramework>

 <GalleryTargetFramework>$(DebugShaderAndGalleryTargetFramework)</GalleryTargetFramework>

 <TargetFrameworks Condition=" '$(Configuration)' == 'Release' And $(MSBuildProjectName) != $(GalleryAppName) ">net8.0-windows10.0.19041.0;net9.0-windows10.0.19041.0;net10.0-windows10.0.19041.0</TargetFrameworks>
 <TargetFrameworks Condition=" '$(Configuration)' == 'Debug' And $(MSBuildProjectName) != $(GalleryAppName)">$(DebugTargetFramework)</TargetFrameworks>

 <TargetFrameworks Condition=" '$(Configuration)' == 'Release' And $(MSBuildProjectName) == $(ShaderLibName) ">net8.0-windows10.0.22621.0;net9.0-windows10.0.22621.0;net10.0-windows10.0.22621.0</TargetFrameworks>
 <TargetFrameworks Condition=" '$(Configuration)' == 'Debug' And $(MSBuildProjectName) == $(ShaderLibName)">$(DebugShaderAndGalleryTargetFramework)</TargetFrameworks>