QBHelper - Step 1

QuickBloxHelper.java

QBPrivateChatManagerListener privateChatManagerListener;
QBMessageListener<QBPrivateChat> privateChatMessageListener;

public void initFramework() {
  //.. 
  privateChatMessageListener = new QBMessageListener<QBPrivateChat>() {
        @Override
        public void processMessage(QBPrivateChat qbPrivateChat, QBChatMessage qbChatMessage) {
            if (qbChatMessage.isMarkable()) {
                int opponentId = qbPrivateChat.getParticipant();
                QBDialog dialog = getDialogOfOpponent(opponentId);
                if (null == dialog) { // We don't have this chat's dialog.
                    retrieveDialogs();
                }
            }
        }

        @Override
        public void processError(QBPrivateChat qbPrivateChat, QBChatException e, QBChatMessage qbChatMessage) {
            //.. 
        }

        @Override
        public void processMessageDelivered(QBPrivateChat qbPrivateChat, String s) {
            //.. 
        }

        @Override
        public void processMessageRead(QBPrivateChat qbPrivateChat, String s) {
            //.. 
        }
  };

  privateChatManagerListener = new QBPrivateChatManagerListener() {
      @Override
      public void chatCreated(final QBPrivateChat privateChat, final boolean createdLocally) {
          privateChat.addMessageListener(privateChatMessageListener);
      }
  };
}

public QBDialog getDialogOfOpponent(int opponentId) {
    for (QBDialog dialog : chatDialogs) {
        if (dialog.getOccupants().contains(opponentId)) {
            return dialog;
        }
    }
    return null;
}