百度地图开发自定义覆盖物事件及样式定制

marker.addEventListener("mouseover",function(){
    this.style.backgroundColor = "#6BADCA";
    this.style.borderColor = "#6BADCA";
    polygon_nc.show();
});
marker.addEventListener("mouseout",function(){
    this.style.backgroundColor = "#EE5D5B";
    this.style.borderColor = "#BC3B3A";
    polygon_nc.hide();
});
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我在百度地图下自定义了一个覆盖物ComplexCustomOverlay作为标注点，覆盖物是放在div里面的，然后我设置了自定义覆盖物的事件
ComplexCustomOverlay.prototype.addEventListener = function (event, fun) {
         this._div['on' + event] = fun;
     }
然后我写了三个事件click mouseover mouseout，
click事件是点击显示信息窗口
map.openInfoWindow(infoWindow1, new BMap.Point(116.407845, 39.914101));
mouseover事件和mouseout事件都是显示一段文字，这段文字放在div控件的span里面
document.getElementsByTagName("span")[0].innerHTML = mouseoverTxt;
然后当我把鼠标放在上面的时候是正常的，但是点击了这个覆盖物以后，那些文字就不是显示在div里面了，而是到了外面，并且竖着显示，求指导 为什么！！！

   
   
   
   

    
    
    
    
     var map = new BMap.Map("container");            // 创建Map实例
     var point = new BMap.Point(116.404, 39.915);    // 创建点坐标
     map.centerAndZoom(point, 15);                     // 初始化地图,设置中心点坐标和地图级别。

     //1、定义构造函数并继承Overlay
     // 定义自定义覆盖物的构造函数
     function ComplexCustomOverlay(point, text, mouseoverText) {
         this._point = point;
         this._text = text;
         this._overText = mouseoverText;
     }
     // 继承API的BMap.Overlay
     ComplexCustomOverlay.prototype = new BMap.Overlay();


     //2、初始化自定义覆盖物
     // 实现初始化方法
     ComplexCustomOverlay.prototype.initialize = function (map) {
         this._map = map;
         var div = this._div = document.createElement("div");
         div.style.position = "absolute";
         div.style.zIndex = BMap.Overlay.getZIndex(this._point.lat);
         div.style.backgroundColor = "#EE5D5B";
         //div.style.border = "1px solid #BC3B3A";
         div.style.color = "white";
         div.style.height = "18px";
         div.style.padding = "2px";
         div.style.lineHeight = "18px";
         div.style.whiteSpace = "nowrap";
         //div.style.MozUserSelect = "none";
         div.style.fontSize = "12px"
         var span = this._span = document.createElement("span");
         div.appendChild(span);
         span.appendChild(document.createTextNode(this._text));
         var that = this;

         var arrow = this._arrow = document.createElement("div");
         arrow.style.background = "url(http://map.baidu.com/fwmap/upload/r/map/fwmap/static/house/images/label.png) no-repeat";
         arrow.style.position = "absolute";
         arrow.style.width = "11px";
         arrow.style.height = "10px";
         arrow.style.top = "22px";
         arrow.style.left = "10px";
         arrow.style.overflow = "hidden";
         div.appendChild(arrow);
         // 将div添加到覆盖物容器中
         map.getPanes().labelPane.appendChild(div);
         // 保存div实例
         this._div = div;

         // 需要将div元素作为方法的返回值，当调用该覆盖物的show、
         // hide方法，或者对覆盖物进行移除时，API都将操作此元素。
         return div;
     }

     //3、绘制覆盖物
     // 实现绘制方法
     ComplexCustomOverlay.prototype.draw = function () {
         var map = this._map;
         var pixel = map.pointToOverlayPixel(this._point);
         this._div.style.left = pixel.x - parseInt(this._arrow.style.left) + "px";
         this._div.style.top = pixel.y - 30 + "px";
     }

     //6、自定义覆盖物添加事件方法
     ComplexCustomOverlay.prototype.addEventListener = function (event, fun) {
         this._div['on' + event] = fun;
     }

     //7、添加自定义覆盖物
     var txt = "银湖海岸城", mouseoverTxt = txt + "| " + parseInt(Math.random() * 1000, 10) + "套";

     var myCompOverlay = new ComplexCustomOverlay(new BMap.Point(116.407845, 39.914101), "银湖海岸城", mouseoverTxt);
     map.addOverlay(myCompOverlay);

     //8、 为自定义覆盖物添加点击事件
     var infoWindow1 = new BMap.InfoWindow("普通标注", { offset: new BMap.Size(30, -30) });
     myCompOverlay.addEventListener("click", function () {
         map.openInfoWindow(infoWindow1, new BMap.Point(116.407845, 39.914101));
         //map.setCenter(new BMap.Point(116.407845, 39.914101));
     });

     myCompOverlay.addEventListener("mouseover", function () {
         if (this._div) {
             this._div.style.backgroundColor = "#6BADCA";
         }
         document.getElementsByTagName("span")[0].innerHTML = mouseoverTxt;
     });

     myCompOverlay.addEventListener("mouseout", function () {
         if (this._div) {
             this._div.style.backgroundColor = "#EE5D5B";
         }
         document.getElementsByTagName("span")[0].innerHTML = txt;
     });