using System; using System.Runtime.InteropServices; using Foundation; using ObjCRuntime; namespace Test { [Protocol] public interface First { [Abstract] [Export ("doit:withmore")] void DoIt (int a, out int b); } [Protocol] public interface Second { [Abstract] [Export ("doit:withmore")] void DoIt (int a, int b); } [BaseType (typeof (NSObject))] public partial interface Derived : First, Second { } }