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How can I check whether Google Maps is fully loaded?

I’m embedding Google Maps into my web site. Once Google Maps is loaded, I need to kick off a few JavaScript processes.

Is there a way to auto-detect when Google Maps has fully loaded, including tile downloads and all?

A tilesloaded() method exists that is supposed to accomplish exactly this task but it does not work.

The "tilesloaded" event seems to work for me. It fires when the page loads and when I move the map around. On your map, is it just inconsistent, or does it never work?
No, just no. "tilesloaded" as it says will be fired every time new tiles are loaded which means it will not only fire on first load also but also every time you drag map to location where your tiles haven't been loaded yet.
Depends if you use addListener() or addListenerOnce(). You are right about addListener() - thats why I use google.maps.event.addListenerOnce(map, 'tilesloaded', function() {

h
hitautodestruct

This was bothering me for a while with GMaps v3.

I found a way to do it like this:

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

The "idle" event is triggered when the map goes to idle state - everything loaded (or failed to load). I found it to be more reliable then tilesloaded/bounds_changed and using addListenerOnce method the code in the closure is executed the first time "idle" is fired and then the event is detached.

See also the events section in the Google Maps Reference.


It is fired when the map goes to idle state (nothing more will load). Sometimes there might be some tiles that didn't load because of bad connection so even if there are such missing pieces, it will trigger the idle event in the end. If you need to ensure that the map is complete, no missing tiles, etc, you should seek some other way (for example "tilesloaded" event).
it is not working for me.. triggers before anything shows up on my map
-1: Triggers sooner than tiles are loaded/displayed.
-1: for me in chrome and firefox, it consistently fires as soon as the script has loaded but before any tile shows. Maybe it's not apparent on a fast connection, but I am blessed with a very slow one. 'tilesloaded' seems to work though.
Thanks for that solution - I think this is exactly what I needed. What I simply cannot wrap my head around, is why on earth google haven't put in a simple ready hook? :-O
P
Pyry Liukas

I'm creating html5 mobile apps and I noticed that the idle, bounds_changed and tilesloaded events fire when the map object is created and rendered (even if it is not visible).

To make my map run code when it is shown for the first time I did the following:

google.maps.event.addListenerOnce(map, 'tilesloaded', function(){
    //this part runs when the mapobject is created and rendered
    google.maps.event.addListenerOnce(map, 'tilesloaded', function(){
        //this part runs when the mapobject shown for the first time
    });
});

The first tilesloaded function works well for me, but the second tilesloaded function never runs for me.
I'm getting Uncaught ReferenceError: map is not defined. I've tried running the script with a delay and at the end of my other scripts but nothing seems to work.
if you're defining event handlers inside event handlers, you're going to have a bad time. i would strongly suggest you don't do this, here's a slightly less hacky alternative that achieves a similar thing: gist.github.com/cmawhorter/a1b0b6a6b73678b97920f748ebca244b
@SamWillis That was most likely because your map object was not instantiated, I know you said you added it at the end but thats what the error means...that it cant find your map object
h
haffla

In 2018:

var map = new google.maps.Map(...)
map.addListener('tilesloaded', function () { ... })

https://developers.google.com/maps/documentation/javascript/events


tilesloaded is the only solution that correctly waits until KML layers have all rendered
This worked for me but It fired everytime I manipulated the map, in the end I had to use google.maps.event.addListenerOnce(map, 'tilesloaded', function(){} so that i can get it to only fire once. addListenerOnce doesn't seem to be supported on map
2
2 revs, 2 users 89%

If you're using the Maps API v3, this has changed.

In version 3, you essentially want to set up a listener for the bounds_changed event, which will trigger upon map load. Once that has triggered, remove the listener as you don't want to be informed every time the viewport bounds change.

This may change in the future as the V3 API is evolving :-)


I'm not finding this working for me as reliably as looking for the tilesloaded event.
P
Phillip Senn

If you're using web components, then they have this as an example:

map.addEventListener('google-map-ready', function(e) {
   alert('Map loaded!');
});

Terrible comment, its wrong on so many levels dont know where to start.
Why do you say "Terrible comment, it's wrong on so many levels I don't know where to start"?
But why provide a solution using a different framework than just google maps?
Because it's better maybe?
HAHAHAHA @nights
A
Alexander

GMap2::tilesloaded() would be the event you're looking for.

See GMap2.tilesloaded for references.


I've read a lot about the tilesloaded() event and it seems that it is extremely inconsistent on when it fires. Any other options?
d
devlord

Where the variable map is an object of type GMap2:

    GEvent.addListener(map, "tilesloaded", function() {
      console.log("Map is fully loaded");
    });

B
Bala

In my case, Tile Image loaded from remote url and tilesloaded event was triggered before render the image.

I solved with following dirty way.

var tileCount = 0;
var options = {
    getTileUrl: function(coord, zoom) {
        tileCount++;
        return "http://posnic.com/tiles/?param"+coord;
    },
    tileSize: new google.maps.Size(256, 256),
    opacity: 0.5,
    isPng: true
};
var MT = new google.maps.ImageMapType(options);
map.overlayMapTypes.setAt(0, MT);
google.maps.event.addListenerOnce(map, 'tilesloaded', function(){
    var checkExist = setInterval(function() {
        if ($('#map_canvas > div > div > div:nth-child(1) > div:nth-child(1) > div:nth-child(1) > div:nth-child(2) > div > div').length === tileCount) {
            callyourmethod();
            clearInterval(checkExist);
        }
    }, 100); // check every 100ms
});

u
user3454173

For Google Maps V3, to check when google maps is fully loaded.

The trick is a combination of all the submissions on here

First you must create the map example:

let googleMap = new google.maps.Map(document.getElementById(targetMapId), 
{
        zoom: 17,
        mapTypeId: google.maps.MapTypeId.ROADMAP,
        streetViewControl: false,
        styles: [
          {
            featureType: "poi",
            elementType: "labels",
            stylers: [
              {visibility: "off"}
            ]
          }
        ],
      });

Then you need to set a default location for it to load.. it can be anywhere

googleMap.setCenter({
        lat: 26.12269,
        lng: -80.130172
      });

Then finally once it finishes loading the tiles for that location you can process code via the "tilesloaded" eent, this code can include re-centering the map, placing markers etc..

This ensures that the map is loaded before you do something with it

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

Others have suggested the "idle" event as well, but I did not have much luck with that as it was hit or miss for me.

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

Whereas when I used the "tilesloaded" , while I do get a quick blip then jump to the correct map view, it always works...so I went with the lesser of two evils


T
Thiago Silva

This days you know if the map is ready here:

void _onMapCreated(GoogleMapController controller) {
    this.controller = controller;
    _mapIsReady=true; //create this variable
  }

call this method from the map widget

return GoogleMap(
              myLocationEnabled: true,
              //markers: markers,
              markers: Set<Marker>.of(markers.values),
              onMapCreated: _onMapCreated,
              initialCameraPosition: CameraPosition(

                target: _initialPosition,
                zoom: 5.0,
              ),
            );

2
2 revs, 2 users 67%

You could check the GMap2.isLoaded() method every n milliseconds to see if the map and all its tiles were loaded (window.setTimeout() or window.setInterval() are your friends).

While this won't give you the exact event of the load completion, it should be good enough to trigger your Javascript.