Why I cannot reference iOS binding library

Sure, can you provide a secure method for me to send the project to you?

Could you see the Private message option on your side? If not, would you mind sharing the sample on GitHub and attach the link here?

I have pushed my project on GitHub. I removed the project's bin and obj folders because they are too large. This is the link: https://github.com/wwen0/MauiDebug
Thank you for help.

Another question I have is how can I set a file's build action when using VS Code to develop .NET MAUI project? I cannot find "build action" when I right-click the file.

I run the sample and the SDKBasicService (and other 6 objects) cannot be found, and the SDKBasicService is not in ApiDefinition.cs and StructsAndEnums.cs, did you get these files via Sharpie?

Sorry, SDKBasicService is the service that makes the native libraries' basic functionalities available to the cross-platform. It only worked in Android. I removed it to not clutter the project, but I forgot to remove the reference to it. I already deleted the code that made the build fail. After it passes build, you will find that the "using" statement in Platforms/iOS/AppDelegate.cs is not recognized.

SDKBasicService only worked in Android, not iOS because the iOS binding library is not recognized by the iOS Platform. So I removed it. For simplicity, I only added "using" statements in MainActivity.cs and AppDelegate.cs to reference the native library. You can look to see that the "using" statements in MainActivity.cs works, but the "using" statement in AppDelegate.cs does not.

Yes, I reproduce the issue, I cannot add using Com.SAS.CI360;. I create a new iOS binding project and add the project reference, but I can add the "using" statement. It's not clear if there are some settings on your binding project, I will investigate further.

Hello,

The name of your iOS project is MauiDemoApp.Binding.iOS, but the namespace of the ApiDefinition.cs and StructsAndEnums.cs is using Com.SAS.CI360

Please open the properties window of your iOS project, then modify the assembly name and default namespace to Com.SAS.CI360.

The references in .csproj of the MAUI project

<ItemGroup Condition=" '$(TargetPlatformIdentifier)' == 'ios' ">
<!--<ProjectReference Include="..\iOSBinding1\iOSBinding1.csproj" />-->
<ProjectReference Include="..\MauiDemoApp.Binding.iOS\MauiDemoApp.Binding.iOS.csproj" />
</ItemGroup>

Best Regards,

Wenyan Zhang

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I use VS Code for .NET MAUI development. From Command Palette, I can only see two options that are relevant: "iOS Binding Library" and "iOS Class Library". I chose "iOS Binding Library". Also, I followed this link to create the binding library: https://video2.skills-academy.com/en-us/dotnet/maui/migration/ios-binding-projects?view=net-maui-8.0
Apart from .csproj file, I cannot see what else I can change to make the binding library build successful but cannot be referenced by the main project.

I use Visual Studio Code, so there is no project Properties Window. But I did open Visual Studio 2022 to look at an older project and I saw when I changed those settings, I actually added <RootNamespace></RootNamespace> and <AssemblyName></AssemblyName>. So I added them to the iOS binding project. I also updated the cross-platform project's binding project reference as you showed above. But the iOS binding project's namespace is still not recognized in the cross-platform's iOS file AppDelegate.cs. I updated my project in Github. Can you please see if it works for you?
BTW, my older project that I opened in Visual Studio 2022 didn't work either. It also has the binding project.

I have Visual Studio 2022 for Mac. But it will not be supported after August 2024, and I cannot install .net 8.0 SDK on it. So I have to use Visual Studio Code.

You run the project on Mac, right? I tested on my Windows machine by the latest VS2022. I will turn to Mac and test again.

Yes. Since I also have access to a Windows computer, I copied the project to the Windows computer. Somehow the iOS binding project didn't work there. So I deleted it and created a new iOS binding project with the project name matching the namespace defined in ApiDefinitions.cs and StructsAndEnums.cs. It has everything the previous iOS binding project has and the build was successful. However, when I tried to reference the namespace in Platform/iOS/AppDelegate.cs, the namespace was still not recognized. I paired my Windows computer with my Mac computer, so there were no warnings related to the computer not Mac.

Could you add an empty class in your iOS binding project? And see the default namespace of that class, then check if you can reference the namespace in Platform/iOS/AppDelegate.cs.

I tried. I added a C# class with a namespace in the iOS binding project, and I can reference both the namespace and the class in Platform/iOS/AppDelegate.cs.

It looks like you solved the problem, right?

Not at all. I need the classes and methods in the native library (the xcframework, or framework) that I added in the iOS binding project to be accessible in Platform/iOS/AppDelegate.cs, not a C# class that I added in the iOS binding project to be accessible. These native classes are generated as C# classes in the iOS binding project's obj/Debug/net8.0-ios/iOS path. They have no visibility in Platform/iOS/AppDelegate.cs, and that is the problem. These generated classes cannot be accessed in the iOS binding project too. So if you want me to try referencing them in the C# class I created in the iOS binding project, that does not work either.

Hi @Wei Wen , I reproduced your issue. Please create a new issue at https://github.com/xamarin/xamarin-macios/issues for further help.

Thank you @Wenyan Zhang (Shanghai Wicresoft Co,.Ltd.) ! I already opened an issue.