public void addCallbackPush(ICallback callback){
  callbacksPush.add(callback);
}

public void addCallbackPush ( ICallback callback ) { callbacksPush . add ( callback ) ; }
adds a callback method to the noteserversynchelper for the synchronization part push local changes to the server . all callbacks will be executed once the synchronization operations are done . after execution the callback will be deleted , so it has to be added again if it shall be executed the next time all synchronize operations are finished .
