code: function switchSelect( selectParentId ) {
          var selects = $G( selectParentId ).children;
          for ( var i = 0, ci; ci = selects[i++]; ) {
              domUtils.on( ci, "click", function () {
                  for ( var j = 0, cj; cj = selects[j++]; ) {
                      cj.className = "";
                      cj.removeAttribute && cj.removeAttribute( "class" );
                  }
                  this.className = "focus";
              } )
          }
      }
docs: 选择切换
  @param selectParentId