advanced-markers-zoom

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

HTML

<!doctype html>
<!--
 @license
 Copyright 2019 Google LLC. All Rights Reserved.
 SPDX-License-Identifier: Apache-2.0
-->

<html>
  <head>
    <title>Advanced Marker Zoom Visibility</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
      center="37.424563902650114,-122.09512859577026"
      zoom="18"
      map-id="4504f8b37365c3d0"></gmp-map>
  </body>
</html>

CSS

/**
 * @license
 * Copyright 2019 Google LLC. All Rights Reserved.
 * SPDX-License-Identifier: Apache-2.0
 */

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

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

JavaScript

'use strict';
/**
 * @license
 * Copyright 2019 Google LLC. All Rights Reserved.
 * SPDX-License-Identifier: Apache-2.0
 */

const mapElement = document.querySelector('gmp-map');

async function init() {
  // Request needed libraries.
  const [{ AdvancedMarkerElement }] = await Promise.all([
    google.maps.importLibrary('marker'),
    google.maps.importLibrary('maps'),
  ]);

  const markerOptions = [
    {
      position: { lat: 37.4239163, lng: -122.094 },
      title: 'This marker is visible at zoom level 15 and higher.',
      minZoom: 14,
    },
    {
      position: { lat: 37.4245, lng: -122.096 },
      title: 'This marker is visible at zoom level 16 and higher.',
      minZoom: 15,
    },
    {
      position: { lat: 37.4249, lng: -122.095 },
      title: 'This marker is visible at zoom level 17 and higher.',
      minZoom: 16,
    },
    {
      position: { lat: 37.425, lng: -122.0955 },
      title: 'This marker is visible at zoom level 18 and higher.',
      minZoom: 17,
    },
  ];

  const markers = [];
  for (const { position, title } of markerOptions) {
    const marker = new AdvancedMarkerElement({ position, title });
    mapElement.append(marker);
    markers.push(marker);
  }

  mapElement.innerMap.addListener('zoom_changed', () => {
    const zoom = mapElement.innerMap.getZoom();
    for (let i = 0; i < markers.length; i++) {
      const { position, minZoom } = markerOptions[i];
      markers[i].position = zoom > minZoom ? position : null;
    }
  });
}

void init();