Loop and add multiple Google Maps markers on an html map

The existing code, as follows does not loop through gmp-map html elements to add markers, It merely adds a marker to one of them. A loop is needed, either in the html itself or via javascript.:

<body>
    <cfoutput>
        <gmp-map
            center="#vLat#,#vLng#"
            zoom="10"
            map-id="DEMO_MAP_ID"
            style="height: 400px"
        >
        <cfloop query="qNearbyTradies">
            <gmp-advanced-marker
                position="#lat#,#lng#"
                title="#company_name# - #sublocality#, #locality#"
                gmpClickable=true
            ></gmp-advanced-marker>
        </cfloop>
    </cfoutput>
</body>
<script src="https://maps.googleapis.com/maps/api/js?callback=initMap&key=[KEY]&libraries=maps,marker&v=beta" async defer></script>
      
    
<script>
    async function initMap() {
        // I assume a javascript loop would begin here somewhere
        const m = document.querySelector("gmp-advanced-marker");
        m.addListener("click", ({ domEvent, latLng }) => {
            const { target } = domEvent;
            const infoWindow = new google.maps.InfoWindow;
            infoWindow.close();
            infoWindow.setContent(m.title);
            infoWindow.open(m.map, m);
        });
    }
    
    window.initMap = initMap;
</script>

I've written some code that generates an array of companies in javascript, but after deciding to generate the map with html, I now already have a loop in the html code and it would make sense to generate all the clickable events within that loop if possible. Looking for pointers on how do achieve that.

Answer

<cfoutput>
    <gmp-map
      id="marker-click-event-example"
      center="-36.8761279,174.83046"
      zoom="8"
      map-id="DEMO_MAP_ID"
    >
      <cfloop query="qNearbyTradies">
        
            <gmp-advanced-marker
              position="#lat#,#lng#"
              title="#company_name# - #sublocality#, #locality#"
              gmp-clickable
            ></gmp-advanced-marker>
        
      </cfloop>
    </gmp-map>
</cfoutput>

    <!-- 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: "[KEY", v: "beta"});</script>



<script>

// This example adds a map using web components.
async function initMap() {
  const { Map } = await google.maps.importLibrary("maps");
  const { AdvancedMarkerElement } = await google.maps.importLibrary("marker");

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

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

  for (const advancedMarker of advancedMarkers) {
    customElements.whenDefined(advancedMarker.localName).then(async () => {
      advancedMarker.addEventListener("gmp-click", async () => {
        const infoWindow = new google.maps.InfoWindow({
          //@ts-ignore
          content: advancedMarker.title,
        });

        infoWindow.open({
          //@ts-ignore
          anchor: advancedMarker,
        });
      });
    });
  }
}

initMap();

Answer

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