Execute callback once when a google map is loaded (google maps api)

gistfile1.js

//Fill in the blanks :)
var map = new google.maps.Map(),
  tileListener = google.maps.event.addListener(map,'tilesloaded',fixMyPageOnce);

function fixMyPageOnce(){
  //immediately remove the listener (or this thing fires for every tile that gets loaded, which is a lot when you start to pan)
  google.maps.event.removeListener(tileListener);
}

You can also use the following and avoid having to remove the listener manually:

google.maps.event.addListenerOnce(map, 'tilesloaded', fixMyPageOnce);

function fixMyPageOnce() {
  // do stuff
  // no need to remove the event listener
}

This will call once the map is finished doing its thing.

  google.maps.event.addListenerOnce(map, 'idle', function(){
        // do something only the first time the map is loaded
  });