标记图标的OpenLayers问题

我正在我的网站上创建OSM地图，并使用openlayer添加一些标记。。我的问题是，我总是得到相同的标记图标

 <script type="text/javascript">

 var map = new OpenLayers.Map("heatMap");
    var mapnik = new OpenLayers.Layer.OSM();
    map.addLayer(mapnik);
    map.setCenter(new OpenLayers.LonLat(-4.0575942987957,54.390175926091) // Center of the map
      .transform(
        new OpenLayers.Projection("EPSG:4326"), // transform from WGS 1984
        new OpenLayers.Projection("EPSG:900913") // to Spherical Mercator Projection
      ), 6 // Zoom level
    );

    var markers = new OpenLayers.Layer.Markers( "Markers" );
    map.addLayer(markers);

    var icon1 = new OpenLayers.Icon('http://www.openlayers.org/dev/img/marker.png', size, offset);
    var icon2 = new OpenLayers.Icon('http://www.openlayers.org/dev/img/marker-gold.png', size, offset);
    var icon3 = new OpenLayers.Icon('http://www.openlayers.org/dev/img/marker-green.png', size, offset);

    var lonLat1 = new OpenLayers.LonLat(-4.0575942987957,54.390175926091).transform(
                            new OpenLayers.Projection("EPSG:4326"), // transform from WGS 1984
                            map.getProjectionObject() // to Spherical Mercator Projection
                            );

    var lonLat2 = new OpenLayers.LonLat(-3.0575942987957,54.390175926091).transform(
                            new OpenLayers.Projection("EPSG:4326"), // transform from WGS 1984
                            map.getProjectionObject() // to Spherical Mercator Projection
                            );

    var lonLat3 = new OpenLayers.LonLat(-5.0575942987957,54.390175926091).transform(
                            new OpenLayers.Projection("EPSG:4326"), // transform from WGS 1984
                            map.getProjectionObject() // to Spherical Mercator Projection
                            );

    var marker1 = new OpenLayers.Marker(lonLat1);
    var feature = new OpenLayers.Feature(markers, lonLat);
    feature.closeBox = true;
    feature.popupClass = OpenLayers.Class(OpenLayers.Popup.AnchoredBubble, { autoSize: true });
    feature.data.popupContentHTML = '<p>Marker1<p>';
    feature.data.overflow = "hidden";

    marker1.feature = feature;

    var markerClick = function (evt) {
        if (this.popup == null) {
            this.popup = this.createPopup(this.closeBox);
            map.addPopup(this.popup);
            this.popup.show();
        } else {
            this.popup.toggle();
        }
        OpenLayers.Event.stop(evt);
    };
    marker1.events.register("mousedown", feature, markerClick);

    var marker2 = new OpenLayers.Marker(lonLat2);
    var feature = new OpenLayers.Feature(markers, lonLat);
    feature.closeBox = true;
    feature.popupClass = OpenLayers.Class(OpenLayers.Popup.AnchoredBubble, { autoSize: true });
    feature.data.popupContentHTML = '<p>Marker2<p>';
    feature.data.overflow = "hidden";

    marker2.feature = feature;

    var markerClick = function (evt) {
        if (this.popup == null) {
            this.popup = this.createPopup(this.closeBox);
            map.addPopup(this.popup);
            this.popup.show();
        } else {
            this.popup.toggle();
        }
        OpenLayers.Event.stop(evt);
    };
    marker2.events.register("mousedown", feature, markerClick);

    var marker3 = new OpenLayers.Marker(lonLat3);
    var feature = new OpenLayers.Feature(markers, lonLat);
    feature.closeBox = true;
    feature.popupClass = OpenLayers.Class(OpenLayers.Popup.AnchoredBubble, { autoSize: true });
    feature.data.popupContentHTML = '<p>Marker 3<p>';
    feature.data.overflow = "hidden";

    marker3.feature = feature;

    var markerClick = function (evt) {
        if (this.popup == null) {
            this.popup = this.createPopup(this.closeBox);
            map.addPopup(this.popup);
            this.popup.show();
        } else {
            this.popup.toggle();
        }
        OpenLayers.Event.stop(evt);
    };
    marker3.events.register("mousedown", feature, markerClick);

    markers.addMarker(marker1, icon1);

    markers.addMarker(marker2, icon2);

    markers.addMarker(marker3, icon3);

var map=新的OpenLayers.map（“热图”）；
var mapnik=new OpenLayers.Layer.OSM（）；
map.addLayer（mapnik）；
map.setCenter（新OpenLayers.LonLat（-4.0575942987957,54.390175926091）//地图中心
.变换(
新OpenLayers.Projection（“EPSG:4326”），//从WGS 1984转换而来
新OpenLayers.Projection（“EPSG:900913”）//到球形墨卡托投影
)，6//缩放级别
);
var markers=新的OpenLayers.Layer.markers（“markers”）；
添加图层（标记）；
var icon1=新的OpenLayers.Icon（'http://www.openlayers.org/dev/img/marker.png，大小，偏移量）；
var icon2=新的OpenLayers.Icon（'http://www.openlayers.org/dev/img/marker-gold.png，大小，偏移量）；
var icon3=新的OpenLayers.Icon（'http://www.openlayers.org/dev/img/marker-green.png，大小，偏移量）；
var lonLat1=新的OpenLayers.LonLat（-4.0575942987957,54.390175926091）。转换(
新OpenLayers.Projection（“EPSG:4326”），//从WGS 1984转换而来
map.getProjectionObject（）//到球形墨卡托投影
);
var lonLat2=新的OpenLayers.LonLat（-3.0575942987957,54.390175926091）。转换(
新OpenLayers.Projection（“EPSG:4326”），//从WGS 1984转换而来
map.getProjectionObject（）//到球形墨卡托投影
);
var lonLat3=新的OpenLayers.LonLat（-5.0575942987957,54.390175926091）。转换(
新OpenLayers.Projection（“EPSG:4326”），//从WGS 1984转换而来
map.getProjectionObject（）//到球形墨卡托投影
);
var marker1=新的OpenLayers.Marker（lonLat1）；
var feature=新的OpenLayers.feature（标记，lonLat）；
feature.closeBox=true；
feature.popupClass=OpenLayers.Class（OpenLayers.Popup.anchoredubble，{autoSize:true}）；
feature.data.popupContentHTML='Marker1'；
feature.data.overflow=“隐藏”；
marker1.feature=特征；
var markerClick=函数（evt）{
if（this.popup==null）{
this.popup=this.createPopup（this.closeBox）；
map.addPopup（this.popup）；
this.popup.show（）；
}否则{
this.popup.toggle（）；
}
OpenLayers.Event.stop（evt）；
};
marker1.events.register（“mousedown”，feature，markerClick）；
var marker2=新的OpenLayers.Marker（lonLat2）；
var feature=新的OpenLayers.feature（标记，lonLat）；
feature.closeBox=true；
feature.popupClass=OpenLayers.Class（OpenLayers.Popup.anchoredubble，{autoSize:true}）；
feature.data.popupContentHTML='Marker2'；
feature.data.overflow=“隐藏”；
marker2.feature=特征；
var markerClick=函数（evt）{
if（this.popup==null）{
this.popup=this.createPopup（this.closeBox）；
map.addPopup（this.popup）；
this.popup.show（）；
}否则{
this.popup.toggle（）；
}
OpenLayers.Event.stop（evt）；
};
marker2.events.register（“mousedown”，feature，markerClick）；
var marker3=新的OpenLayers.Marker（lonLat3）；
var feature=新的OpenLayers.feature（标记，lonLat）；
feature.closeBox=true；
feature.popupClass=OpenLayers.Class（OpenLayers.Popup.anchoredubble，{autoSize:true}）；
feature.data.popupContentHTML='标记3'；
feature.data.overflow=“隐藏”；
marker3.feature=特征；
var markerClick=函数（evt）{
if（this.popup==null）{
this.popup=this.createPopup（this.closeBox）；
map.addPopup（this.popup）；
this.popup.show（）；
}否则{
this.popup.toggle（）；
}
OpenLayers.Event.stop（evt）；
};
marker3.events.register（“mousedown”，feature，markerClick）；
markers.addMarker（marker1，icon1）；
markers.addMarker（marker2，icon2）；
markers.addMarker（marker3，icon3）；

---

现在的问题是，所有三个标记都有相同的图标。。。有人能帮我吗..

在创建标记实例后更改图标

marker = new ....
var size = new OpenLayers.Size(25, 12);
var offset = new OpenLayers.Pixel(-(size.w / 2), -size.h);
marker.icon = new OpenLayers.Icon("marker.png", size, offset);
//UPDATE AGAIN
marker.icon.size = size;
marker.icon.offset = offset;
marker.draw();