.NET for Android error XA0000
An unhandled exception (or error case) was encountered in one of .NET for Android's MSBuild tasks.
Consider submitting a bug if you are getting this warning under normal circumstances.
An exception was thrown and logged, including a C# exception stack trace showing where the failure occurred.
Likely, the only option is to submit a bug.
You are using a $(TargetFrameworkVersion)
which cannot be mapped
to a valid android api-level.
Check you have selected a valid $(TargetFrameworkVersion)
and the
required android api-level is installed in
$(AndroidSdkDirectory)\platforms.