Javascript – Google Maps: Auto close open InfoWindows

Call the marker.setIcon('newImage.png')... Look here for the docs.

Are you asking about the actual way to do it? You could just create each div, and a add a mouseover and mouseout listener that would change the icon and back for the markers.

With version 3 of the Google Maps API, the easiest way to do this may be by grabbing a custom icon set, like the one that Benjamin Keen has created here:

http://www.benjaminkeen.com/google-maps-coloured-markers/

If you put all of those icons at the same place as your map page, you can colorize a Marker simply by using the appropriate icon option when creating it:

var beachMarker = new google.maps.Marker({
  position: myLatLng,
  map: map,
  icon: 'brown_markerA.png'
});

This is super-easy, and is the approach I'm using for the project I'm working on currently.