NET8.0 Unable to compile the project when using Static Library about xamarin-macios

[rolfbjarne]

The problem is that your binding project says these two fields exist in the library:

[Static]
partial interface Constants
{
    // extern double TURecipientBarVersionNumber;
    [Field("TURecipientBarVersionNumber", "__Internal")]
    double TURecipientBarVersionNumber { get; }

    // extern const unsigned char [] TURecipientBarVersionString;
    [Field("TURecipientBarVersionString", "__Internal")]
    NSString TURecipientBarVersionString { get; }
}

but they don't:

$ nm RecipientBarBinding/Lib/libServiceRecipientBar.a | grep TURecipientBarVersionNumber
[no output]

$ nm RecipientBarBinding/Lib/libServiceRecipientBar.a | grep TURecipientBarVersionString
[no output]

it looks like they're in the framework though:

$ nm RecipientBarBinding/Lib/TURecipientBar.framework/TURecipientBar | grep TURecipientBarVersionString
0000000000010190 S _TURecipientBarVersionString

$ nm RecipientBarBinding/Lib/TURecipientBar.framework/TURecipientBar | grep TURecipientBarVersionNumber
00000000000101c8 S _TURecipientBarVersionNumber

So maybe try adding the framework instead of the static library to the binding project?

Also note that we recommend using an .xcframework instead of either a framework or a static library, because an .xcframework can contain native bits for all architectures (neither a framework nor a static library can contain arm64 bits for both the simulator and device, while an xcframework can).

[rameshkec85]

Thanks for the reply @rolfbjarne But the same library works for net7.0

[rolfbjarne]

I see, this is the consequence of a bug fix we did in .NET 8.

In .NET 7 the library compiles, but the properties in question (Constants.TURecipientBarVersionNumber and Constants.TURecipientBarVersionString) do not. If you try to call them, you'll get 0 or null back. This is because the native properties have been linked away by the native linker.

The fix we did was to ask the native linker to keep the native property for any such managed binding - with the downside that if the native property doesn't actually exist, you'll now get a build error.

The fix is to make sure the native library has everything you're binding in your binding project (in your case you could do that by removing the bindings for these properties).