OpenLayers With StreetView Overlay

Question

Im trying to add StreetView functionality to my OpenLayers web app, and would like to add the overlay showing StreetView availability to the map itself. I have seen an example of it being done successfully here, but i cannot get the code to work in my own solution. Specifically :

var layer = new OpenLayers.Layer.Google("Google Street", {sphericalMercator: true});

layer.mapObject.addOverlay(new GStreetviewOverlay());

results in the error:

layer.mapObject is null

Has anyone got any idea what i might be doing wrong, and if so, how can i fix this?

Thanks in advance!

C

Answer 1

Openlayers with Streetview

requires the GeoExt ux extension

all the code is available - so you can see what you are missing

(if you could post a live link to your current map - users could debug it for you.)

http://api.geo.admin.ch/main/wsgi/doc/build/api/streetview.html

Answer 2

To use Google layers and meet licensing requirements you have to access Google layers through the Google API. When you add a Google layer to an OpenLayers map OpenLayers loads the Google API.

The layer.mapObject (as opposed to layer.map which is the OL map object) should give you a reference to the Google Map. As this is null something has gone wrong loading the Google API. You can check in FireBug if it has loaded correctly.

The example you point to may be using the older Google 2 API rather than version 3. You no longer need an API key and can add in the Google API using:

<script src="http://maps.google.com/maps/api/js?sensor=false"></script>

Have a look at the unit tests for the Google v3 API layers which may help you.

Remember the StreetView also needs Flash in the browser.

Answer 3

layer.mapObject is null ecause the mapObject property is created after that the layer is added to the map. try this:

var layer = new OpenLayers.Layer.Google("Google Street", {sphericalMercator: true});
map.addLayer(layer);
layer.mapObject.addOverlay(new GStreetviewOverlay());