--- a/Framework/Messages/ObserverBase.h	Tue Oct 15 13:46:01 2019 +0200
+++ b/Framework/Messages/ObserverBase.h	Tue Oct 15 14:08:15 2019 +0200
@@ -23,6 +23,7 @@
 
 #include "ICallable.h"
 #include "IObserver.h"
+#include "IObservable.h"
 
 #include <Core/OrthancException.h>
 
@@ -54,5 +55,12 @@
     {
       return new Callable<TObserver, TMessage>(GetSharedObserver(), MemberMethod);
     }
+
+    template <typename TMessage>
+    void Register(IObservable& observable,
+                  void (TObserver::* MemberMethod) (const TMessage&))
+    {
+      observable.RegisterCallable(CreateCallable(MemberMethod));
+    }
   };
 }