code: function clickHandler( tabHeads,tabBodys,obj ) {
      //head样式更改
      for ( var k = 0, len = tabHeads.length; k < len; k++ ) {
          tabHeads[k].className = "";
      }
      obj.className = "focus";
      //body显隐
      var tabSrc = obj.getAttribute( "tabSrc" );
      for ( var j = 0, length = tabBodys.length; j < length; j++ ) {
          var body = tabBodys[j],
              id = body.getAttribute( "id" );
          if ( id != tabSrc ) {
              body.style.zIndex = 1;
          } else {
              body.style.zIndex = 200;
          }
      }
  
  }
docs: 给tab注册切换事件 
  tab点击处理事件
  @param tabHeads
  @param tabBodys
  @param obj