Which is the correct way for publishing WPF app with XAML island in Microsoft Store?

Question

Hello, so I have a WPF app with XAML island which I'm trying to publish to MS store using the Windows Application Packaging Project with references to the WPF and UWP project(as per requirement "If you want to publish your app in the Microsoft Store, you have to add reference to the UWP project in the packaging project" from https://learn.microsoft.com/en-us/windows/apps/desktop/modernize/host-custom-control-with-xaml-islands. The built package app passes Windows app certification kit, but when submitted in MS Store, it fails the pre validation with "This package wasn't built for submission to the Microsoft Store. Make sure you're uploading a Release build with the .NET Native tool chain enabled", which is true - the UWP project is not build with the Net Native toolchain (and all examples that I found weren't using Net Native for the XAML islands). Anyway, I decided to build the UWP project with net native, and this time the package again passes Windows app certification kit and it additionally passed the pre validation of MS Store, but then the submission got cancelled with 'UIAutomationClientSideProviders' is a mixed mode assembly containing managed and native code. Only pure managed assemblies are compatible with .NET Native. So now I'm puzzled how to actually package the app so it can be submitted to MS Store

Answer 1

Hello, Welcome to Micorosoft Q&A,

"This package wasn't built for submission to the Microsoft Store. Make sure you're uploading a Release build with the .NET Native tool chain enabled",

For the first problem, it looks you have not build your app in released mode, Please edit the edit the build config make sure the package created within released mode.

but then the submission got cancelled with 'UIAutomationClientSideProviders' is a mixed mode assembly containing managed and native code. Only pure managed assemblies are compatible with .NET Native.

For this problem, it is hard to detect, you need check if has used mixed mode assembly in your solution. And I'd suggest you open a free support ticket here: Contact Us. Choose to Contact us, select Dashboard for Topic, and select App submissions and management for issue type. And you could also post this problem in xamlisland GitHub issue box.

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