What is the proper way to support both arm and arm64 for a native library

MichaelHartman

I have a native library (cpp) which does decoding of data into a bitmap. If I set the native library project to target ARM everything works great on non-ARM64 devices. On ARM64 devices it cannot find/load the .so file. (DLLNotFound Exception)

If I target ARM64 the reverse happens.

I have the Native Library as a project in my solution (VS2017 Enterprise) and the project is added as a reference in the main Android project.
There are other non-native libraries as well that call the functions in the native library.

I don't reference the native library in non-native ones because I get an error "Native library references target platform arm64-v8a which is not supported by this project. Configured supported ABIs are: armeabi" when building the non-native library. This seems odd and likely a clue, but I cannot find a way to specify this for a library like you can for the App project.

I am confused as to why the ARM build doesn't work for both. But regardless, what is the proper way to set this up?

BillyLiu

@MichaelHartman

I am confused as to why the ARM build doesn't work for both. But regardless, what is the proper way to set this up?

ARM and ARM64 are two different architecture, so they need two .so file to support.
You could refer to the following link for how to support different architecture:
https://docs.microsoft.com/en-us/xamarin/android/platform/native-libraries

CarlosCM

Hi, @MichaelHartman!

I have been struggling with this problem for months, and still have not found a solution.

Now that Google is forcing everyone to support 64 bits architecture, I'm going to go 100% C#, although this is less than ideal...

The only thing I have seen is this article recently released: https://blog.xamarin.com/using-c-libraries-xamarin-forms-apps/ BUT it doesn't talk about how to produce the native libraries, which is the issue.

Did you found a solution for this?