code: @Override
  	public void onAboutToHide() {
  		log.debug(getId() + ": onAboutToHide with refreshPolicy: "
  				+ dataProvider.getRefreshPolicy());
  		super.onAboutToHide();
  
  		this.dataProvider.removeDataProviderListener(this);
  		unRegisterListeners();
  		if (detailForm instanceof Widget) {
  			((Widget) detailForm).onAboutToHide();
  		}
  
  		if (dataProvider.getRefreshPolicy() == DataProvider.RefreshPolicy.ALLWAYS) {
  			getTableWidget().setRows(Collections.EMPTY_LIST);
  		}
  	}
docs: {@inheritDoc}