code: public void setControlGroup(boolean value, boolean linkable) {
          if (value) {
              createControlGroup(linkable);
          } else if (controlGroup != null) {
              if (anchorPanel != null) remove(anchorPanel);
              else if (anchor != null) getElement().removeChild(anchor);
              anchor = null;
              anchorPanel = null;
              setSplitHref(null);
              controlGroupRoot = null;
              controlGroup = null;
              checkBoxInput = null;
          }
      }
docs: true - prepare and allow to add widgets to this list box item.
  
  @param linkable - if true &lt;a> will be forcefully created, so row will be clickable.