you have included the Google Maps API multiple times on this page. This may cause unexpected errors

Question

I get two error when using google map:

1. Warning: you have included the Google Maps API multiple times on this page. This may cause unexpected errors.
2. a is null (main.js)

i don't know if there is any connection between the two, but the final result is that my page cannot load the map.

here is my head tag:

<script type="text/javascript" src="../s/Jquery/jquery-1.6.1.min.js"></script>
<script type="text/javascript" src="../s/jquery.placeholder.min.js"></script>
<script type="text/javascript" src="../s/index.js"></script>
<script type="text/javascript" src="../s/Jquery/ui/jquery.ui.core.js"></script>
<script type="text/javascript" src="../s/Jquery/ui/jquery.ui.widget.js"></script>

<script type="text/javascript" src="../s/Jquery/ui/jquery.ui.position.js"></script>
<script type="text/javascript" src="../s/Jquery/ui/jquery.ui.autocomplete.js"></script>
<script src="../dd/markerclusterer_compiled.js" type="text/javascript"></script><script src="../dd/dealers_js.js" type="text/javascript"></script><script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=false"></script>

here is the function which i call the google map:

function set_google_map(set_region)
{

        var zoom;
        var center;
        switch (set_region) {
            case "usa":
                zoom = 3;
                center = new google.maps.LatLng(37.09, -95.71);
                break;
            case "europe":
                zoom = 3;
                center = new google.maps.LatLng(48.58, 7.71);
                break;
            case "east":
                zoom = 3;
                center = new google.maps.LatLng(31, 121);
                break;
            default:
                zoom = 1;
                center = new google.maps.LatLng(35, 5);
        }
        // Creating the map  
        map = new google.maps.Map(document.getElementById('map'), options);
        google.maps.event.addListener(map, 'click', function(){
            clean_icons();
            if (infowindow) 
                infowindow.close();
        });
        map.setCenter(center);
        map.setZoom(zoom);


            //bounds = new google.maps.LatLngBounds();  
}

these are my variables:

var UseridEncr;
var super_category="ATE";
var infowindow;
var map;
var bounds;
var image="../dd/i/green.png";
var image_active="../dd/i/red.png";
var mc ;
var location_changed=true;
var current_region="usa";
var mcOptions = {gridSize:30, maxZoom: 8};
var last_marker;
var last_marker_z;
var DealersData ;
var markers=[];
var markers_selected=[];
claster_markers=[];
var current_view=0;
myData={};
var selected_items=[];
var total_selected=0;

thanks for your prompt answer.

Answer 1

I faced the same type of problem. This occurs if your web page including maps api more than one time.

I have checked in my case there was a .js file that was also calling maps api, so please first check if you are including maps api more than one time, if you are, remove the one.

Answer 2

For those who append Google Map script to DOM on runtime, you should remove traces of Google Map before you re-append the next time.

You can unload google map script by following 2 steps:

• Remove google map scripts from DOM.
• Remove google from BOM (window object).

---

Example

declare var window;


function removeGoogleMapScript() {
    console.debug('removing google script...');
    let keywords = ['maps.googleapis'];

    //Remove google from BOM (window object)
    window.google = undefined;

    //Remove google map scripts from DOM
    let scripts = document.head.getElementsByTagName("script");
    for (let i = scripts.length - 1; i >= 0; i--) {
        let scriptSource = scripts[i].getAttribute('src');
        if (scriptSource != null) {
            if (keywords.filter(item => scriptSource.includes(item)).length) {
                scripts[i].remove();
                // scripts[i].parentNode.removeChild(scripts[i]);
            }
        }
    }
}


function addGoogleMapScript() {
    removeGoogleMapScript();
    console.debug('adding google script...');
    let dynamicScripts = [`https://maps.googleapis.com/maps/api/js?v=quarterly&key=123yourApiKey`];
    for (let i = 0; i < dynamicScripts.length; i++) {
        let node = document.createElement('script');
        node.src = dynamicScripts[i];
        node.type = 'text/javascript';
        node.async = false;
        node.charset = 'utf-8';
        node.onload = uponFinishLoadingScript; //probably to initialise your map or something
        document.head.appendChild(node);
    }
}