web-components-events

Sample code supporting Google Maps Platform JavaScript API documentation. author(s): Geo Developer IX Documentation Team

HTML

<!doctype html>
<!--
@license
Copyright 2026 Google LLC. All Rights Reserved.
SPDX-License-Identifier: Apache-2.0
-->

<html>
  <head>
    <title>Add a Map Web Component with Events</title>

    <script>
      // prettier-ignore
      (g=>{var h,a,k,p="The Google Maps JavaScript API",c="google",l="importLibrary",q="__ib__",m=document,b=window;b=b[c]||(b[c]={});var d=b.maps||(b.maps={}),r=new Set,e=new URLSearchParams,u=()=>h||(h=new Promise(async(f,n)=>{await (a=m.createElement("script"));e.set("libraries",[...r]+"");for(k in g)e.set(k.replace(/[A-Z]/g,t=>"_"+t[0].toLowerCase()),g[k]);e.set("callback",c+".maps."+q);a.src=`https://maps.${c}apis.com/maps/api/js?`+e;d[q]=f;a.onerror=()=>h=n(Error(p+" could not load."));a.nonce=m.querySelector("script[nonce]")?.nonce||"";m.head.append(a)}));d[l]?console.warn(p+" only loads once. Ignoring:",g):d[l]=(f,...n)=>r.add(f)&&u().then(()=>d[l](f,...n))})({
            });
    </script>
  </head>
  <body>
    <gmp-map
      id="marker-click-event-example"
      center="43.4142989,-124.2301242"
      zoom="4"
      map-id="DEMO_MAP_ID">
      <gmp-advanced-marker
        position="37.4220656,-122.0840897"
        title="Mountain View, CA"
        gmp-clickable></gmp-advanced-marker>
      <gmp-advanced-marker
        position="47.648994,-122.3503845"
        title="Seattle, WA"
        gmp-clickable></gmp-advanced-marker>
    </gmp-map>
  </body>
</html>

CSS

/**
 * @license
 * Copyright 2026 Google LLC. All Rights Reserved.
 * SPDX-License-Identifier: Apache-2.0
 */

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

JavaScript

'use strict';
/**
 * @license
 * Copyright 2026 Google LLC. All Rights Reserved.
 * SPDX-License-Identifier: Apache-2.0
 */

// This example adds a map using web components.
async function init() {
  void google.maps.importLibrary('marker'); // preload
  const { InfoWindow } = await google.maps.importLibrary('maps');

  console.log('Maps JavaScript API loaded.');

  const advancedMarkers = document.querySelectorAll(
    '#marker-click-event-example gmp-advanced-marker'
  );

  for (const advancedMarker of advancedMarkers) {
    void customElements.whenDefined(advancedMarker.localName).then(() => {
      advancedMarker.addEventListener('gmp-click', () => {
        const infoWindow = new InfoWindow({
          content: advancedMarker.title,
        });

        infoWindow.open({
          anchor: advancedMarker,
        });
      });
    });
  }
}

void init();