Adding codes to handle no ndnd exception
diff --git a/src/chatdialog.h b/src/chatdialog.h
index 4e7ab59..2e6ea1c 100644
--- a/src/chatdialog.h
+++ b/src/chatdialog.h
@@ -195,6 +195,9 @@
   void
   closeChatDialog(const ndn::Name& chatroomPrefix);
 
+  void
+  noNdnConnection(const QString& msg);
+
 public slots:
   void 
   processTreeUpdate(const std::vector<Sync::MissingDataInfo>);