diff --git a/src/chat-dialog-backend.hpp b/src/chat-dialog-backend.hpp
index f01c015..f8133f7 100644
--- a/src/chat-dialog-backend.hpp
+++ b/src/chat-dialog-backend.hpp
@@ -125,6 +125,12 @@
   void
   chatPrefixChanged(ndn::Name newChatPrefix);
 
+  void
+  eraseInRoster(ndn::Name sessionPrefix, ndn::Name::Component chatroomName);
+
+  void
+  addInRoster(ndn::Name sessionPrefix, ndn::Name::Component chatroomName);
+
 public slots:
   void
   sendChatMessage(QString text, time_t timestamp);