Circles

constmapElement=document.querySelector('gmp-map')!;
letinnerMap:google.maps.Map;
asyncfunctioninit(){
// Request needed libraries.
const[{Circle},{AdvancedMarkerElement},{event}]=
awaitPromise.all([
google.maps.importLibrary('maps'),
google.maps.importLibrary('marker'),
google.maps.importLibrary('core'),
]);
// Set the initial map center point.
constinitialCenter={lat:34.98956821576194,lng:135.74239981260283};// Hotel Emion, Kyoto, Japan
// Get the inner map.
innerMap=mapElement.innerMap;
// Get the buttons.
constbuttons=document.querySelectorAll('input[name="radius"]');
// Create the circle.
constwalkingCircle=newCircle({
strokeColor:'#ffdd00ff',
strokeOpacity:0.8,
strokeWeight:2,
fillColor:'#ffdd00ff',
fillOpacity:0.35,
map:innerMap,
center:initialCenter,
radius:400,
draggable:true,
editable:false,
});
// Define a "Crosshair" vector icon
constparser=newDOMParser();
constsvgString=`<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="-6 -6 12 12"><path d="M -6,0 L 6,0 M 0,-6 L 0,6" stroke="black" stroke-width="1"/></svg>`;
constpinSvg=parser.parseFromString(
svgString,
'image/svg+xml'
).documentElement;
constcenterMarker=newAdvancedMarkerElement({
position:initialCenter,
title:'A marker using a custom SVG image.',
anchorLeft:'-50%',
anchorTop:'-50%',
});
centerMarker.append(pinSvg);
mapElement.append(centerMarker);
// Wait for the map to finish drawing its tiles.
event.addListenerOnce(innerMap,'tilesloaded',()=>{
// Get the controls div
constcontrols=document.getElementById('control-panel');
// Display controls once map is loaded.
if(controls){
controls.style.display='block';
}
});
// Add event listener to update the radius based on user selection.
buttons.forEach((button)=>{
button.addEventListener('change',(changeEvent)=>{
consttarget=changeEvent.targetasHTMLInputElement;
walkingCircle.setRadius(Number(target.value));
});
});
// Handle user click, reset the map center and position the circle.
innerMap.addListener(
'click',
(
mapsMouseEvent:
google.maps.MapMouseEvent|google.maps.IconMouseEvent
)=>{
constnewCenter=mapsMouseEvent.latLng;
if(!newCenter)return;
walkingCircle.setCenter(newCenter);
centerMarker.position=newCenter;
innerMap.panTo(newCenter);
}
);
// Handle user dragging the circle, update the center marker position.
walkingCircle.addListener('center_changed',()=>{
centerMarker.position=walkingCircle.getCenter();
});
}
voidinit();
index.ts 

constmapElement=document.querySelector('gmp-map');
letinnerMap;
asyncfunctioninit(){
// Request needed libraries.
const[{Circle},{AdvancedMarkerElement},{event}]=
awaitPromise.all([
google.maps.importLibrary('maps'),
google.maps.importLibrary('marker'),
google.maps.importLibrary('core'),
]);
// Set the initial map center point.
constinitialCenter={lat:34.98956821576194,lng:135.74239981260283};// Hotel Emion, Kyoto, Japan
// Get the inner map.
innerMap=mapElement.innerMap;
// Get the buttons.
constbuttons=document.querySelectorAll('input[name="radius"]');
// Create the circle.
constwalkingCircle=newCircle({
strokeColor:'#ffdd00ff',
strokeOpacity:0.8,
strokeWeight:2,
fillColor:'#ffdd00ff',
fillOpacity:0.35,
map:innerMap,
center:initialCenter,
radius:400,
draggable:true,
editable:false,
});
// Define a "Crosshair" vector icon
constparser=newDOMParser();
constsvgString=`<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="-6 -6 12 12"><path d="M -6,0 L 6,0 M 0,-6 L 0,6" stroke="black" stroke-width="1"/></svg>`;
constpinSvg=parser.parseFromString(
svgString,
'image/svg+xml'
).documentElement;
constcenterMarker=newAdvancedMarkerElement({
position:initialCenter,
title:'A marker using a custom SVG image.',
anchorLeft:'-50%',
anchorTop:'-50%',
});
centerMarker.append(pinSvg);
mapElement.append(centerMarker);
// Wait for the map to finish drawing its tiles.
event.addListenerOnce(innerMap,'tilesloaded',()=>{
// Get the controls div
constcontrols=document.getElementById('control-panel');
// Display controls once map is loaded.
if(controls){
controls.style.display='block';
}
});
// Add event listener to update the radius based on user selection.
buttons.forEach((button)=>{
button.addEventListener('change',(changeEvent)=>{
consttarget=changeEvent.target;
walkingCircle.setRadius(Number(target.value));
});
});
// Handle user click, reset the map center and position the circle.
innerMap.addListener('click',(mapsMouseEvent)=>{
constnewCenter=mapsMouseEvent.latLng;
if(!newCenter)return;
walkingCircle.setCenter(newCenter);
centerMarker.position=newCenter;
innerMap.panTo(newCenter);
});
// Handle user dragging the circle, update the center marker position.
walkingCircle.addListener('center_changed',()=>{
centerMarker.position=walkingCircle.getCenter();
});
}
voidinit();
index.js 

/* 
 * Optional: Makes the sample page fill the window. 
 */
html,
body{
height:100%;
margin:0;
padding:0;
}
#control-panel{
display:none;/* Set to 'display: block' after the map loads. */
background-color:#fff;
border:2pxsolid#fff;
border-radius:3px;
box-shadow:02px6pxrgba(0,0,0,0.3);
font-family:'Roboto',sans-serif;
font-size:medium;
margin:10px;
padding:10px;
}
style.css 

<html>
 <head>
 <title>Circles</title>
 <link rel="stylesheet" type="text/css" href="./style.css" />
 <script type="module" src="./index.js"></script>
 <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))})({
 key: "GOOGLE_MAPS_API_KEY"
 });
 </script>
 </head>
 <body>
 <gmp-map
 center="34.98956821576194, 135.74239981260283"
 zoom="15"
 map-id="DEMO_MAP_ID">
 <div id="control-panel" slot="control-inline-start-block-start">
 <input
 id="short-walk"
 type="radio"
 name="radius"
 value="400"
 checked />
 <label for="short-walk">Short Walk (~5 minutes)</label><br />
 <input
 id="medium-walk"
 type="radio"
 name="radius"
 value="800" />
 <label for="medium-walk">Medium Walk (~15 minutes)</label><br />
 <input id="long-walk" type="radio" name="radius" value="1600" />
 <label for="long-walk">Long Walk (~30 minutes) </label>
 </div>
 </gmp-map>
 </body>
</html>
index.html