Synchronous Loading

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In this example, the Maps API is loaded synchronously. We omitted the async and defer attributes from the script tag that loads the API, and we also omitted the callback parameter.

<html>
  <head>
    <title>Synchronous Loading</title>
    <script src="https://polyfill.io/v3/polyfill.min.js?features=default"></script>

    <link rel="stylesheet" type="text/css" href="./style.css" />
    <script type="module" src="./index.js"></script>
  </head>
  <body>
    <div id="map"></div>
    <script src="https://maps.googleapis.com/maps/api/js?key=AIzaSyB41DRUbKWJHPxaFjMAwdrzWzbVKartNGg&v=weekly"></script>
  </body>
</html>

When the API is loaded synchronously, subsequent script tags will not execute until the API is fully loaded. Because of this, the final script tag can call new google.maps.Map and assume that google.maps.Map has been defined.

Read the documentation.

TypeScript

const map = new google.maps.Map(document.getElementById("map") as HTMLElement, {
  center: { lat: -34.397, lng: 150.644 },
  zoom: 8,
});

declare global {
  interface Window {
    map: google.maps.Map;
  }
}
window.map = map;

JavaScript

const map = new google.maps.Map(document.getElementById("map"), {
  center: { lat: -34.397, lng: 150.644 },
  zoom: 8,
});

window.map = map;

CSS

/* 
 * Always set the map height explicitly to define the size of the div element
 * that contains the map. 
 */
#map {
  height: 100%;
}

/* 
 * Optional: Makes the sample page fill the window. 
 */
html,
body {
  height: 100%;
  margin: 0;
  padding: 0;
}

HTML

<html>
  <head>
    <title>Synchronous Loading</title>
    <script src="https://polyfill.io/v3/polyfill.min.js?features=default"></script>

    <link rel="stylesheet" type="text/css" href="./style.css" />
    <script type="module" src="./index.js"></script>
  </head>
  <body>
    <div id="map"></div>
    <script src="https://maps.googleapis.com/maps/api/js?key=AIzaSyB41DRUbKWJHPxaFjMAwdrzWzbVKartNGg&v=weekly"></script>
  </body>
</html>

Try Sample

Clone Sample

Git and Node.js are required to run this sample locally. Follow these instructions to install Node.js and NPM. The following commands clone, install dependencies and start the sample application.

  git clone -b sample-map-sync https://github.com/googlemaps/js-samples.git
  cd js-samples
  npm i
  npm start

Other samples can be tried by switching to any branch beginning with sample-SAMPLE_NAME.

  git checkout sample-SAMPLE_NAME
  npm i
  npm start