docs: public void toggleFocus(boolean focusOn) {
  
          if (focusOn) {
              addStyleName(formCss().focused());
              if (CmsStringUtil.isNotEmptyOrWhitespaceOnly(m_help) || m_hasError) {
                  if (shouldDisplayTooltipAbove()) {
                      addStyleName(formCss().displayAbove());
                  } else {
                      removeStyleName(formCss().displayAbove());
                  }
              } else {
                  m_helpBubble.getStyle().setDisplay(Display.NONE);
              }
          } else {
              removeStyleName(formCss().focused());
              if (m_widget != null) {
                  if (m_handler.hasSingleOptionalValue()) {
                      if (m_handler.getWidgetService().shouldRemoveLastValueAfterUnfocus(m_widget)) {
                          m_handler.removeAttributeValue(this);
                      }
  
                  }
              }
          }
      }