Develop Reference

Google marker is not being displayed on map

I have written code to display a marker on a googlemap. The code is copied almost verbatim, from the Google API docs. Yet the marker is not displaying on the page.
Here is my code: What am I doing wrong?
var map;
var central_location = new google.maps.LatLng(42.745334, 12.738430);
function initialize() {
var mapCanvas = document.getElementById('map');
var mapOptions = {
center: central_location,
zoom: 14,
mapTypeId: google.maps.MapTypeId.ROADMAP
}
map = new google.maps.Map(mapCanvas, mapOptions);
}
google.maps.event.addDomListener(window, 'load', initialize);
$(document).ready(function() {
var infowindow = new google.maps.InfoWindow({
content: '<div>Hello</div>'
});
var marker = new google.maps.Marker({
position: central_location,
map: map,
title: 'This is the title'
});
marker.addListener('click', function() {
infowindow.open(map, marker);
});
marker.setMap(map);
});
#map {
width: 500px;
height: 380px;
}
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js" type="text/javascript" style=""></script>
<script src="https://maps.googleapis.com/maps/api/js"></script>
<div id="map"></div>
I notice that there are similar questions, the only thing that seems to be different with my question is that I am creating my marker in the jQuery ready() event - NOT the initialize() function.
Is this why the marker is not been displayed?
Note: I don't remember reading anything in the Google API docs that states that markers should be created when the map is being created, so that can't obviously be the case

Move your marker creation to the initialize function.
$(document).ready(function(){}) works when DOM elements are loaded, which doesn't necessarily mean that the map is loaded. So if you try to create the marker in the document ready function, the map might not be created then, once the map is ready map variable has the map object, so you can make the marker on that, and you can add the markers dynamically after the map is loaded.
var map;
var central_location = new google.maps.LatLng(42.745334, 12.738430);
function initialize() {
console.log('map loaded');
var mapCanvas = document.getElementById('map');
var mapOptions = {
center: central_location,
zoom: 14,
streetViewControl: false,
mapTypeId: google.maps.MapTypeId.ROADMAP
}
map = new google.maps.Map(mapCanvas, mapOptions);
makePin(42.745334, 12.738430);
}
google.maps.event.addDomListener(window, 'load', initialize);
$(document).ready(function(){
console.log('document loaded');
})
function makePin(lat, long){
var marker = new google.maps.Marker({
position: new google.maps.LatLng(lat, long),
map: map,
title: 'This is the title'
});
var infowindow = new google.maps.InfoWindow({
content: '<div>Hello</div>'
});
marker.addListener('click', function() {
infowindow.open(map, marker);
});
}
#map {
width: 500px;
height: 380px;
}
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js" type="text/javascript" style=""></script>
<script src="https://maps.googleapis.com/maps/api/js"></script>
<button onclick="makePin(42.749334, 12.739430)">Add Pin</button>
<div id="map"></div>

How can you make marker without loaded map. Map need to initialize first then marker will work
function initialize() {
var mapCanvas = document.getElementById('map');
var mapOptions = {
center: central_location,
zoom: 14,
streetViewControl: false,
mapTypeId: google.maps.MapTypeId.ROADMAP
}
map = new google.maps.Map(mapCanvas, mapOptions);
var marker = new google.maps.Marker({
position: central_location,
map: map,
title: 'This is the title'
});
marker.addListener('click', function () {
infowindow.open(map, marker);
});
marker.setMap(map);
}

Here is the solution:
var map;
var central_location = new google.maps.LatLng(42.745334, 12.738430);
function initialize() {
var mapCanvas = document.getElementById('map');
var mapOptions = {
center: central_location,
zoom: 14,
streetViewControl: false,
mapTypeId: google.maps.MapTypeId.ROADMAP
}
map = new google.maps.Map(mapCanvas, mapOptions);
var marker = new google.maps.Marker({
position: central_location,
map: map,
title: 'This is the title'
});
marker.addListener('click', function() {
infowindow.open(map, marker);
});
marker.setMap(map);
}
google.maps.event.addDomListener(window, 'load', initialize);
$(document).ready(function() {
var infowindow = new google.maps.InfoWindow({
content: '<div>Hello</div>'
});
});
#map {
width: 500px;
height: 380px;
}
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js" type="text/javascript" style=""></script>
<script src="https://maps.googleapis.com/maps/api/js"></script>
<div id="map"></div>

google map not rendering under .collapse bootstrap

I have looked every where and am starting to go crazy. I know I am close, but can't get it.
I have my html:
<div id="glasgow-map" class="collapse">
<div class="map">
<div id="map-canvas" style="width:100%; height:350px;"></div>
</div>
</div><!--end collapse-->
my JS is:
function initialize() {
var myLatlng = new google.maps.LatLng(55.860949,-4.244938);
var mapOptions = {
zoom: 16,
center: myLatlng
}
var map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
var marker = new google.maps.Marker({
position: myLatlng,
map: map,
title: 'Taylor Hopkinson Associates'
});
}
google.maps.event.addDomListener(window, 'load', initialize);
$('#glasgow-map').on('shown.bs.collapse', function () {
google.maps.event.trigger(map, "resize");
map.setCenter(center);
})
From all the other info I have seen I know I need the (map, "resize) but I am getting this error in the console:
Uncaught ReferenceError: map is not defined
Any help would be fantastic. It's been a long day!!

Thanks for your Help #kamlesh, I think you are right, but this is the way I finally managed to get it to work, and also for multiple maps - if anyone needs help with that, it's below.
I stripped the google.maps.event.addDomListener(window, 'load', initialize); and added the initialize to the .collapse button for when it is clicked. This way there is no need for the resize.
function initialize() {
var myLatlng = new google.maps.LatLng(55.860949,-4.244938);
var myLatlng2 = new google.maps.LatLng(51.510142,-0.143314);
var myLatlng3 = new google.maps.LatLng(51.4004236,0.0172711);
var mapOptions = {
zoom: 16,
center: myLatlng,
mapTypeId: google.maps.MapTypeId.ROADMAP
}
var mapOptions2 = {
zoom: 16,
center: myLatlng2,
mapTypeId: google.maps.MapTypeId.ROADMAP
}
var mapOptions3 = {
zoom: 16,
center: myLatlng3,
mapTypeId: google.maps.MapTypeId.ROADMAP
}
var map = new google.maps.Map(document.getElementById('map-canvas1'), mapOptions);
var map2 = new google.maps.Map(document.getElementById('map-canvas2'), mapOptions2);
var map3 = new google.maps.Map(document.getElementById('map-canvas3'), mapOptions3);
var marker = new google.maps.Marker({
position: myLatlng,
map: map,
title: 'Taylor Hopkinson Associates'
});
var marker2 = new google.maps.Marker({
position: myLatlng2,
map: map2,
title: 'Taylor Hopkinson Associates'
});
var marker3 = new google.maps.Marker({
position: myLatlng3,
map: map3,
title: 'Taylor Hopkinson Associates'
});
}
$('#glasgow-map').on('shown.bs.collapse', function (e) {
initialize();
})
$('#london-map').on('shown.bs.collapse', function (e) {
initialize();
})
$('#bromley-map').on('shown.bs.collapse', function (e) {
initialize();
})
Perhaps there is a way of streamlining this code, but it certainly works for me.

Adding Marker to Google Map

I'm creating a map using the Javascript API, and I'm having some trouble getting the markers to show up.
I've followed this tutorial to create the map, which works well:
https://developers.google.com/maps/tutorials/fundamentals/adding-a-google-map
I've then followed this tutorial to add the marker, but it's not loading:
https://developers.google.com/maps/documentation/javascript/examples/marker-simple
Here's my code now:
<script>
function initialize() {
var map_canvas = document.getElementById('map_canvas');
var map_options = {
center: new google.maps.LatLng(43.643296, -79.408475),
zoom: 15,
mapTypeId: google.maps.MapTypeId.ROADMAP }
var map = new google.maps.Map(map_canvas, map_options, marker);
var marker = new google.maps.Marker({
position: myLatlng,
map: map,
title:"Hello World!" });
}
google.maps.event.addDomListener(window, 'load', initialize);
</script>

This line
var map = new google.maps.Map(map_canvas, map_options, marker);
is wrong. mapconstructor has only two arguments. It should be
var map = new google.maps.Map(map_canvas, map_options);
And myLatlng is not defined. So, you can change your code to:
function initialize() {
myLatlng = new google.maps.LatLng(43.643296, -79.408475);
var map_canvas = document.getElementById('map');
var map_options = {
center: myLatlng,
zoom: 15,
mapTypeId: google.maps.MapTypeId.ROADMAP }
var map = new google.maps.Map(map_canvas, map_options);
var marker = new google.maps.Marker({
position: myLatlng,
map: map,
title:"Hello World!" });
}

Use this url you will get your answer http://www.w3schools.com/googleAPI/google_maps_overlays.asp

Adding markers to google earth

How can I add new marker to the map? I managed to show the map function startGoogleMaps()
but my function (onclick()), does not work.
function startGoogleMaps(){
var map = new google.maps.Map(document.getElementById('canvasMap'), {
zoom: 5,
center: initCenter,
mapTypeId: google.maps.MapTypeId.ROADMAP
});
}
document.getElementById("testButton").onclick = function(){
var marker = new google.maps.Marker({
position: (37, -97),
map: map,
title:"Hello World!"});
}

Try defining the map object in the same scope as you are binding the click event:
var map = null;
function startGoogleMaps(){
map = new google.maps.Map(document.getElementById('canvasMap'), {
zoom: 5,
center: initCenter,
mapTypeId: google.maps.MapTypeId.ROADMAP
});
}
document.getElementById("testButton").onclick = function(){
var marker = new google.maps.Marker({
position: (37, -97),
map: map,
title:"Hello World!"});
}
Also note that you need to pass your position as an instance of google.maps.LatLng:
...
position: google.maps.LatLng(37, -97),
...

Keep in mind that Javascript uses functional scope. You'll need to declare map globally like so:
var map;
function startGoogleMaps(){
map = new google.maps.Map(document.getElementById('canvasMap'), {
zoom: 5,
center: initCenter,
mapTypeId: google.maps.MapTypeId.ROADMAP
});
}
document.getElementById("testButton").onclick = function(){
var marker = new google.maps.Marker({
position: new google.maps.LatLng(37, -97),
map: map,
title:"Hello World!"});
}
In addition, the marker itself may be outside the scope of your map, so you can use map.fitBounds to display it properly:
document.getElementById("testButton").onclick = function(){
var marker = new google.maps.Marker({
position: new google.maps.LatLng(37, -97),
map: map,
title:"Hello World!"});
var latlngbounds = new google.maps.LatLngBounds();
latlngbounds.extend(new google.maps.LatLng(37, -97));
map.fitBounds(latlngbounds);
}

Add Marker function with Google Maps API

I have the following Javascript that includes both the standard Google Maps API initialize() function and custom addMarker() function. The map will load fine however the marker does not get added to the map.
<script type="text/javascript">
// Standard google maps function
function initialize() {
var myLatlng = new google.maps.LatLng(40.779502, -73.967857);
var myOptions = {
zoom: 12,
center: myLatlng,
mapTypeId: google.maps.MapTypeId.ROADMAP
}
map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);
}
// Function for adding a marker to the page.
function addMarker(location) {
marker = new google.maps.Marker({
position: location,
map: map
});
}
// Testing the addMarker function
CentralPark = new google.maps.LatLng(37.7699298, -122.4469157);
addMarker(CentralPark);
</script>

You have added the add marker method call outside the function and that causes it to execute before the initialize method which will be called when google maps script loads and thus the marker is not added because map is not initialized
Do as below....
Create separate method TestMarker and call it from initialize.
<script type="text/javascript">
// Standard google maps function
function initialize() {
var myLatlng = new google.maps.LatLng(40.779502, -73.967857);
var myOptions = {
zoom: 12,
center: myLatlng,
mapTypeId: google.maps.MapTypeId.ROADMAP
}
map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);
TestMarker();
}
// Function for adding a marker to the page.
function addMarker(location) {
marker = new google.maps.Marker({
position: location,
map: map
});
}
// Testing the addMarker function
function TestMarker() {
CentralPark = new google.maps.LatLng(37.7699298, -122.4469157);
addMarker(CentralPark);
}
</script>

function initialize() {
var location = new google.maps.LatLng(44.5403, -78.5463);
var mapCanvas = document.getElementById('map_canvas');
var map_options = {
center: location,
zoom: 15,
mapTypeId: google.maps.MapTypeId.ROADMAP
}
var map = new google.maps.Map(map_canvas, map_options);
new google.maps.Marker({
position: location,
map: map
});
}
google.maps.event.addDomListener(window, 'load', initialize);

THis is other method
You can also use setCenter method with add new marker
check below code
$('#my_map').gmap3({
action: 'setCenter',
map:{
options:{
zoom: 10
}
},
marker:{
values:
[
{latLng:[position.coords.latitude, position.coords.longitude], data:"Netherlands !"}
]
}
});

<div id="map" style="width:100%;height:500px"></div>
<script>
function myMap() {
var myCenter = new google.maps.LatLng(51.508742,-0.120850);
var mapCanvas = document.getElementById("map");
var mapOptions = {center: myCenter, zoom: 5};
var map = new google.maps.Map(mapCanvas, mapOptions);
var marker = new google.maps.Marker({position:myCenter});
marker.setMap(map);
}
</script>
<script src="https://maps.googleapis.com/maps/api/js?key=AIzaSyBu-916DdpKAjTmJNIgngS6HL_kDIKU0aU&callback=myMap"></script>

Below code works for me:
<script src="http://maps.googleapis.com/maps/api/js"></script>
<script>
var myCenter = new google.maps.LatLng(51.528308, -0.3817765);
function initialize() {
var mapProp = {
center:myCenter,
zoom:15,
mapTypeId:google.maps.MapTypeId.ROADMAP
};
var map = new google.maps.Map(document.getElementById("googleMap"), mapProp);
var marker = new google.maps.Marker({
position: myCenter,
icon: {
url: '/images/marker.png',
size: new google.maps.Size(70, 86), //marker image size
origin: new google.maps.Point(0, 0), // marker origin
anchor: new google.maps.Point(35, 86) // X-axis value (35, half of marker width) and 86 is Y-axis value (height of the marker).
}
});
marker.setMap(map);
}
google.maps.event.addDomListener(window, 'load', initialize);
</script>
<body>
<div id="googleMap" style="width:500px;height:380px;"></div>
</body>
Reference link