public void undo()
  {
    if (DEBUG) log("Attempting to undo TaskEdit");
    if (taskViewsToUpdate != null)
    {
      if (DEBUG) log("currentState Completed? " + currentState.isCompleted());
      if (DEBUG) log("previousState Completed? " + previousState.isCompleted());
      if (DEBUG) log("Revert task to previous state");
      currentState.updateFrom(previousState);
      if (DEBUG) log("currentState completed after revert? " + currentState.isCompleted());
      if (DEBUG) log("Update taskViews");
      for (TaskView taskView : taskViewsToUpdate)
      {
        taskView.updateTaskInfo();
      }
    }
  }