百度地图自定义覆盖物

    <script>
    var map = new BMap.Map('allmap');
    var Bcenter = new BMap.Point(116.404,39.915);
    map.centerAndZoom(Bcenter,11);
    
    //自定义的覆盖物
    function myOverlay(point,text,mouseoverText){
        this._point = point;
        this._text = text;
        this._overtext = mouseoverText;
    }
    
    //继承overlay的API
    myOverlay.prototype = new BMap.Overlay();
     
    //初始化自定义覆盖物
    myOverlay.prototype.initialize = function(map){
        this._map = map;
        //创建div标签
        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';
        //创建span标签
        var span = this._span = document.createElement('span');
        div.appendChild(span);
        span.appendChild(document.createTextNode(this._text));
        var that = this;
        
        //箭头的穿件
        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);
        //标签绑定事件
    /*div.onmouseover = function(){
            this.style.backgroundColor = "#6BADCA";
            this.style.borderColor = "#0000ff";
            this.getElementsByTagName("span")[0].innerHTML = that._overtext;
            arrow.style.backgroundPosition = "0px -20px";
        }

        div.onmouseout = function(){
            this.style.backgroundColor = "#EE5D5B";
            this.style.borderColor = "#BC3B3A";
            this.getElementsByTagName("span")[0].innerHTML = that._text;
            arrow.style.backgroundPosition = "0px 0px";
        }
        */
        //添加到覆盖物的容器中
        map.getPanes().labelPane.appendChild(div);
        return div;
    }
    
    //绘制覆盖物
    myOverlay.prototype.draw = function(){
        var map = this._map;
        var pixel = map.pointToOverlayPixel(this._point);
        this._div.style.left = pixel.x - parseInt(this._arrow.left) + 'px';
        this._div.style.top = pixel.y - 30 + 'px';
    }
    
    //覆盖物显示
    myOverlay.prototype.show = function(){
        if(this._div){
            this._div.style.display = '';
        
        }
    }
    
    //隐藏覆盖物
    myOverlay.prototype.hide = function(){
        if(this._div){
            this._div.style.display = 'none';
        }
    }
    
    //自定义覆盖物添加事件
    myOverlay.prototype.addEventListener = function (event, fun) {
        this._div['on' + event] = fun;
    
    }
    
    var myoverlay = new myOverlay(Bcenter,'鼠标上来看看','鼠标下去看看');
    map.addOverlay(myoverlay);
    myoverlay.addEventListener('click',function(){
        alert('注册点击事件');
    })
    </script>