In my app, I may fire off zoom change events programmatically, either via setZoom()
, fitBounds()
, or setOptions()
.
MAN = {};
MAN.globalMap = google.maps.Map(document.getElementById('map'));
I then route all programmatic calls to set the zoom through wrapper functions that flip a flag to false
before they go on to set the zoom.
MAN.savedZoom = MAN.globalMap.getZoom();
MAN.saveZoomFlag = true;
// we want it to always be true, unless zoom was
// changed programatically.
MAN.setZoom = function setZoom(zoomLevel) {
console.log("won't save that I'm setting zoomLevel to " + zoomLevel);
this.saveZoomFlag = false;
MAN.globalMap.setZoom(zoomLevel);
};
MAN.fitBounds = function fitBounds(bounds) {
console.log("setting bounds, won't save zoomlevel.");
this.saveZoomFlag = false;
MAN.globalMap.fitBounds(bounds);
};
MAN.setOptions = function setOptions(options) {
console.log("setting options, won't save zoomlevel.");
this.saveZoomFlag = false;
MAN.globalMap.setOptions(options);
};
I then declare a listeners. At first I was declaring only the first, and was puzzled that it wasn't working:
google.maps.event.addListener(
MAN.globalMap,
'zoom_changed',
function zoom_changed_listener() {
console.log(
"zoom changed to " +
MAN.globalMap.getZoom() + "; " +
(MAN.saveZoomFlag ? "saving." : "not saving.")
);
if (MAN.saveZoomFlag) {
console.trace("saving");
MAN.savedZoom = MAN.globalMap.getZoom();
}
MAN.saveZoomFlag = true;
}
);
you may also find the idle
event helpful, however, if you're just trying to avoid the initial set. See more about the maps events here: https://developers.google.com/maps/documentation/javascript/events