code: public void setSelectAllText(final String selectAllText) {
          if (selectAllText != null)
              attrMixin.setAttribute(SELECT_ALL_TEXT, selectAllText);
          else
              attrMixin.removeAttribute(SELECT_ALL_TEXT);
      }
docs: The text on the button that selects all options when
  <b>actionsBox</> is enabled.<br>
  <br>
  Defaults to <code>Select All</code>.
  
  @param selectAllText