/**   * Returns a random lat lng position within the map bounds.   * @param {!google.maps.Map} map   * @return {!google.maps.LatLngLiteral}   */functiongetRandomPosition(map){constbounds=map.getBounds();constminLat=bounds.getSouthWest().lat();constminLng=bounds.getSouthWest().lng();constmaxLat=bounds.getNorthEast().lat();constmaxLng=bounds.getNorthEast().lng();constlatRange=maxLat-minLat;// Note: longitude can span from a positive longitude in the west to a// negative one in the east. e.g. 150lng (150E) <-> -30lng (30W) is a large// span that covers the whole USA.letlngRange=maxLng-minLng;if(maxLng <minLng){lngRange+=360;}return{lat:minLat+Math.random()*latRange,lng:minLng+Math.random()*lngRange,};}consttotal=100;constintersectionObserver=newIntersectionObserver((entries)=>{for(constentryofentries){if(entry.isIntersecting){entry.target.classList.add('drop');intersectionObserver.unobserve(entry.target);}}});asyncfunctioninitMap():Promise<void>{// Request needed libraries.const{Map}=awaitgoogle.maps.importLibrary("maps")asgoogle.maps.MapsLibrary;const{AdvancedMarkerElement,PinElement}=awaitgoogle.maps.importLibrary("marker")asgoogle.maps.MarkerLibrary;constposition={lat:37.4242011827985,lng:-122.09242296450893};constmap=newMap(document.getElementById("map")asHTMLElement,{zoom:14,center:position,mapId:'4504f8b37365c3d0',});// Create 100 markers to animate.google.maps.event.addListenerOnce(map,'idle',()=>{for(leti=0;i <100;i++){createMarker(map,AdvancedMarkerElement,PinElement);}});// Add a button to reset the example.constcontrolDiv=document.createElement("div");constcontrolUI=document.createElement("button");controlUI.classList.add("ui-button");controlUI.innerText="Reset the example";controlUI.addEventListener("click",()=>{// Reset the example by reloading the map iframe.refreshMap();});controlDiv.appendChild(controlUI);map.controls[google.maps.ControlPosition.TOP_CENTER].push(controlDiv);}functioncreateMarker(map,AdvancedMarkerElement,PinElement){constpinElement=newPinElement();constcontent=pinElement.element;constadvancedMarker=newAdvancedMarkerElement({position:getRandomPosition(map),map:map,content:content,});content.style.opacity='0';content.addListener('animationend',(event)=>{content.classList.remove('drop');content.style.opacity='1';});consttime=2+Math.random();// 2s delay for easy to see the animationcontent.style.setProperty('--delay-time',time+'s');intersectionObserver.observe(content);}functionrefreshMap(){// Refresh the map.constmapContainer=document.getElementById('mapContainer');constmap=document.getElementById('map');map!.remove();constmapDiv=document.createElement('div');mapDiv.id='map';mapContainer!.appendChild(mapDiv);initMap();}initMap();
index.ts

/**   * Returns a random lat lng position within the map bounds.   * @param {!google.maps.Map} map   * @return {!google.maps.LatLngLiteral}   */functiongetRandomPosition(map){constbounds=map.getBounds();constminLat=bounds.getSouthWest().lat();constminLng=bounds.getSouthWest().lng();constmaxLat=bounds.getNorthEast().lat();constmaxLng=bounds.getNorthEast().lng();constlatRange=maxLat-minLat;// Note: longitude can span from a positive longitude in the west to a// negative one in the east. e.g. 150lng (150E) <-> -30lng (30W) is a large// span that covers the whole USA.letlngRange=maxLng-minLng;if(maxLng <minLng){lngRange+=360;}return{lat:minLat+Math.random()*latRange,lng:minLng+Math.random()*lngRange,};}consttotal=100;constintersectionObserver=newIntersectionObserver((entries)=>{for(constentryofentries){if(entry.isIntersecting){entry.target.classList.add('drop');intersectionObserver.unobserve(entry.target);}}});asyncfunctioninitMap(){// Request needed libraries.const{Map}=awaitgoogle.maps.importLibrary("maps");const{AdvancedMarkerElement,PinElement}=awaitgoogle.maps.importLibrary("marker");constposition={lat:37.4242011827985,lng:-122.09242296450893};constmap=newMap(document.getElementById("map"),{zoom:14,center:position,mapId:'4504f8b37365c3d0',});// Create 100 markers to animate.google.maps.event.addListenerOnce(map,'idle',()=>{for(leti=0;i <100;i++){createMarker(map,AdvancedMarkerElement,PinElement);}});// Add a button to reset the example.constcontrolDiv=document.createElement("div");constcontrolUI=document.createElement("button");controlUI.classList.add("ui-button");controlUI.innerText="Reset the example";controlUI.addEventListener("click",()=>{// Reset the example by reloading the map iframe.refreshMap();});controlDiv.appendChild(controlUI);map.controls[google.maps.ControlPosition.TOP_CENTER].push(controlDiv);}functioncreateMarker(map,AdvancedMarkerElement,PinElement){constpinElement=newPinElement();constcontent=pinElement.element;constadvancedMarker=newAdvancedMarkerElement({position:getRandomPosition(map),map:map,content:content,});content.style.opacity='0';content.addListener('animationend',(event)=>{content.classList.remove('drop');content.style.opacity='1';});consttime=2+Math.random();// 2s delay for easy to see the animationcontent.style.setProperty('--delay-time',time+'s');intersectionObserver.observe(content);}functionrefreshMap(){// Refresh the map.constmapContainer=document.getElementById('mapContainer');constmap=document.getElementById('map');map.remove();constmapDiv=document.createElement('div');mapDiv.id='map';mapContainer.appendChild(mapDiv);initMap();}initMap();
index.js

<html>  <head>    <title>Advanced Markers CSS Animation</title>    <link rel="stylesheet" type="text/css" href="./style.css" />    <script type="module" src="./index.js"></script>  </head>  <body>    <div>      <div></div>    </div>    <!-- prettier-ignore -->    <script>(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))})        ({key: "AIzaSyA6myHzS10YXdcazAFalmXvDkrYCp5cLc8", v: "weekly"});</script>  </body></html>
index.html