code: function(ev){
      var _self = this,
        tipGroup = _self.get('tipGroup');
      var canvasNode = _self.get('canvas').get('node');
      _self.clearActivedItem();
      //标志从显示到隐藏
      if(tipGroup && tipGroup.get('visible')){
        if(tipGroup.get('shared')){
          Util.each(_self.getVisibleSeries(),function(series){
            var markers = series.get('markersGroup');
            markers && markers.clearActivedItem();
            series.clearActivedItem && series.clearActivedItem();
          });
          //ev 不存在或者 ev.toElement不在canvas内部
          //火狐等浏览器用ev.relatedTarget替换ev.toElement
          if(ev && ev.relatedTarget){
            ev.toElement = ev.relatedTarget
          }
          if(!ev || !(Util.contains(canvasNode,ev.toElement) || (canvasNode === ev.toElement)) ){
            _self._hideTip();
          }
          return;
        }
        _self._hideTip();
      }
    }
docs: 处理隐藏tip事件