docs: public boolean addSubPanels(Container parent, int options)
      {
          String strScreen = this.getProperty(Params.SCREEN);
          if ((strScreen == null) || (strScreen.length() == 0))
              this.setProperty(Params.SCREEN, INITIAL_SCREEN);
          boolean success = super.addSubPanels(parent, options);
          if (success)
          	if (strScreen == null)
          		this.getProperties().remove(Params.SCREEN);
          return success;
      }