Unit Test App (Android) Tests are not shown in Test Explorer

Hello,

For my existing Xamarin.Android project, I wanted add Unit Tests.

I created new project from template as below;

I also installed required packages;

Here is my sample test class;

After I successfully build my test project, "LoadNewsCategoriesTest" method does not appear in Test Explorer.
But if I build entire solution, then only test methods from MsTest projects appear, but no tests shown from Xamarin.Android.Test projects.

Am I missing something here?