Vector title attribute can't display?

Question

var vectormap = new OpenLayers.Layer.Vector('Overlay',
    {
        styleMap: new OpenLayers.StyleMap(
        {
            "default": new OpenLayers.Style({
                           externalGraphic: 'girl.png',
                           graphicWidth: 50,
                           graphicHeight: 50,
                           graphicYOffset: -24,
                           title: 'marker'}),
            "select": new OpenLayers.Style({
                           externalGraphic: 'boy.png',
                           graphicWidth: 16,
                           graphicHeight: 26,
                           graphicYOffset: -24,
                           title: 'marker_select'})
        })
    });
featurearray = new OpenLayers.Feature.Vector(new OpenLayers.Geometry.Point(113.950,33.019));
vectormap.addFeatures([ featurearray ]); 

This is my vector layer, but a bit wrong, my png image title attribute can not be displayed when the mouse to move up, I checked the official website the "OSM with Marker and Popup.html" code, exactly the same, you know why, thank you!

Answer 1

It looks like you are using canvas but title option does not supported by the canvas renderer. Try to configure you vector layer following way:

var vectormap = new OpenLayers.Layer.Vector('Overlay',
{
    styleMap: new OpenLayers.StyleMap(
    {
        "default": new OpenLayers.Style({
                       externalGraphic: 'girl.png',
                       graphicWidth: 50,
                       graphicHeight: 50,
                       graphicYOffset: -24,
                       title: 'marker'}),
        "select": new OpenLayers.Style({
                       externalGraphic: 'boy.png',
                       graphicWidth: 16,
                       graphicHeight: 26,
                       graphicYOffset: -24,
                       title: 'marker_select'})
    })
    renderers: ["SVG", "VML", "Canvas"]
});