@NotNull
  @Override
  public ActionCallback getReady(@NotNull Object requestor) {
    /*
    final ActionCallback callback = myViewPanel.getActionCallback();
    return callback == null ? ActionCallback.DONE : callback;
    */
    // TODO: only initial expand
    return ActionCallback.DONE;
  }
@NotNull
  @Override
  public ActionCallback getReady(@NotNull Object requestor)