/**
  * Renders the javascript event once
  *
  * @param Ivory\GoogleMapBundle\Model\Events\Event $eventOnce
  * @return string HTML output
  */
 public function renderEventOnce(Event $eventOnce)
 {
     return sprintf('var %s = google.maps.event.addListenerOnce(%s, "%s", %s);' . PHP_EOL, $eventOnce->getJavascriptVariable(), $eventOnce->getInstance(), $eventOnce->getEventName(), $eventOnce->getHandle());
 }