gis - Remember state of Google Maps v3 -

i displaying map placemarks , kml overlays. when user clicks away, want state of map remembered when user returns.

first question is: can save entire state of map somehow; overlays , everything?

for now, have been saving lat/long , zoom , replaying kml overlays, haven't had success this. save cookies on bounds changed or window unload events, problem loading saved values. reason being map loads asynchronously. i've tried using map idle event, fires more once. seems fire, run code in handler, fire again when it's finished code. infinite loop? anyway, replaying of kml overlay overrides whatever lat/long/zoom specified.

so main question is: how restore saved map overlays?

i don't think google maps can save state of map, have yourself.

you correctly used idle event init overlays. idle event triggered every time map becomes idle after zooming or panning, if want 1 time listener idle event (or other event), can way:

var map = new google.maps.map(document.getelementbyid("map"), myoptions);  var initlistener = google.maps.event.addlistener(map, 'idle', function() {     // code here     google.maps.event.removelistener(initlistener); }); 

if want preserve zoom , center of map after loading kml, have use kmllayer's option preserveviewport:

var kmllayer = new google.maps.kmllayer( mykml.kml, {preserveviewport: true});