code: function() {
          var d = this.panel_div; // "this" refers to a control on panel!
          var re = new RegExp("\\b(" + this.displayClass + "Item)Inactive\\b");
          d.className = d.className.replace(re, "$1Active");
      }
docs: Method: iconOn
  Internal use, for use only with "controls[i].events.on/un".