Keep inner interface method names in proguard

I tried the following and it seemed to work:

-keep interface com.somepackage.SomeClass$someInterface

ProGuard uses the naming convention of Java bytecode, as seen in class file names and stacktraces. Therefore:

-keep public interface com.somepackage.SomeClass$someInterface {*;}

For those who are looking for how to keep a custom annotation (which is defined in a @interface in java) retaining its all members,

you should actually use like below to keep it:

-keep @interface com.your.annotation.interface. {*;}