<html>
<head><title>OpenLayers Marker Popups</title></head>
<body>
<div id="mapdiv"></div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/openlayers/2.11/lib/OpenLayers.js"></script>
<script>
map = new OpenLayers.Map("mapdiv");
map.addLayer(new OpenLayers.Layer.OSM());
epsg4326 = new OpenLayers.Projection("EPSG:4326");
projectTo = map.getProjectionObject();
var lonLat = new OpenLayers.LonLat( -0.1279688 ,51.5077286 ).transform(epsg4326, projectTo);
var zoom=14;
map.setCenter (lonLat, zoom);
var vectorLayer = new OpenLayers.Layer.Vector("Overlay");
var feature = new OpenLayers.Feature.Vector(
new OpenLayers.Geometry.Point( -0.1279688, 51.5077286 ).transform(epsg4326, projectTo),
{description:'This is the value of<br>the description attribute'} ,
{externalGraphic: 'img/marker.png', graphicHeight: 25, graphicWidth: 21, graphicXOffset:-12, graphicYOffset:-25 }
);
vectorLayer.addFeatures(feature);
var feature = new OpenLayers.Feature.Vector(
new OpenLayers.Geometry.Point( -0.1244324, 51.5006728 ).transform(epsg4326, projectTo),
{description:'Big Ben'} ,
{externalGraphic: 'img/marker.png', graphicHeight: 25, graphicWidth: 21, graphicXOffset:-12, graphicYOffset:-25 }
);
vectorLayer.addFeatures(feature);
var feature = new OpenLayers.Feature.Vector(
new OpenLayers.Geometry.Point( -0.119623, 51.503308 ).transform(epsg4326, projectTo),
{description:'London Eye'} ,
{externalGraphic: 'img/marker.png', graphicHeight: 25, graphicWidth: 21, graphicXOffset:-12, graphicYOffset:-25 }
);
vectorLayer.addFeatures(feature);
map.addLayer(vectorLayer);
var controls = {
selector: new OpenLayers.Control.SelectFeature(vectorLayer, { onSelect: createPopup, onUnselect: destroyPopup })
};
function createPopup(feature) {
feature.popup = new OpenLayers.Popup.FramedCloud("pop",
feature.geometry.getBounds().getCenterLonLat(),
null,
'<div class="markerContent">'+feature.attributes.description+'</div>',
null,
true,
function() { controls['selector'].unselectAll(); }
);
map.addPopup(feature.popup);
}
function destroyPopup(feature) {
feature.popup.destroy();
feature.popup = null;
}
map.addControl(controls['selector']);
controls['selector'].activate();
</script>
</body></html>