Creating Multiple Markers with InfoWindows Using Google Maps JavaScript API

[Laura219]

I have a dataset with location information that needs to be displayed on a Google Map. I want to create markers for each location and show details when users click on them.

Here’s my sample data:

var places = [
  ['Central Park', 40.785091, -73.968285, 1],
  ['Times Square', 40.758896, -73.985130, 2], 
  ['Brooklyn Bridge', 40.706086, -73.996864, 3],
  ['Statue of Liberty', 40.689247, -74.044502, 4],
  ['Empire State Building', 40.748817, -73.985428, 5]
];

I need help with the basic implementation to add these markers to the map and make them show an info popup with the location name when clicked. Most examples I found online are too complicated for this simple task.

[liamj]

Marker clustering was a lifesaver when I had tons of markers to deal with. Here’s what worked for me: create a bounds object that auto-adjusts your map viewport to show all markers - no manual zoom math needed. Set up your map, loop through your markers normally, and build the bounds at the same time. Once you’re done adding markers, just call map.fitBounds() and everything displays nicely on any screen size. Pro tip I learned the hard way - if you’re updating markers a lot, throw them in an array so you can clear the old ones before adding new batches. Skip this and you’ll have ghost markers eating up memory. Google’s clustering library is also clutch for cleaning up the visual chaos when markers get bunched together.

[Alex_Thunder]

close your previous infowindows b4 opening new ones or you’ll end up with multiple popups. had this exact problem last week - drove users crazy. easy fix: store a ref to the current infowindow and call close() b4 opening the next one.

[Nova56]

The Problem: You want to display location data on a Google Map, adding markers for each location and showing details in an info window when a marker is clicked. You have your location data in a JavaScript array, but you’re unsure how to implement this efficiently using the Google Maps API.

Step-by-Step Guide:

1. Initialize the Map: First, you need to initialize a Google Map on your web page. This involves including the Google Maps JavaScript API and creating a google.maps.Map object. Make sure you have a valid Google Maps API key.

// Ensure you have included the Google Maps JavaScript API in your HTML file with your API key.
// Example: <script src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&callback=initMap"></script>

function initMap() {
  const mapDiv = document.getElementById('map'); // Replace 'map' with the ID of your map div
  const map = new google.maps.Map(mapDiv, {
    center: { lat: 40.7128, lng: -74.0060 }, // Initial center (adjust as needed)
    zoom: 11 // Initial zoom level (adjust as needed)
  });

  // ... (Rest of the code to add markers and info windows)
}

2. Iterate and Add Markers: Iterate through your places array. For each location, create a google.maps.Marker object and add it to the map.

  var places = [
    ['Central Park', 40.785091, -73.968285, 1],
    ['Times Square', 40.758896, -73.985130, 2],
    ['Brooklyn Bridge', 40.706086, -73.996864, 3],
    ['Statue of Liberty', 40.689247, -74.044502, 4],
    ['Empire State Building', 40.748817, -73.985428, 5]
  ];

  places.forEach(place => {
    const marker = new google.maps.Marker({
      position: { lat: place[1], lng: place[2] },
      map: map,
      title: place[0]
    });

    // ... (Add InfoWindow logic in the next step)
  });

3. Create and Attach InfoWindows: For each marker, create a google.maps.InfoWindow object containing the location name. Attach a click listener to each marker that opens its corresponding info window. Crucially, close any previously open infowindow before opening a new one to avoid multiple popups.

  let currentInfoWindow = null; // Keep track of the currently open infowindow

  places.forEach(place => {
    const marker = new google.maps.Marker({
      position: { lat: place[1], lng: place[2] },
      map: map,
      title: place[0]
    });

    const infoWindow = new google.maps.InfoWindow({
      content: place[0]
    });

    marker.addListener('click', () => {
      if (currentInfoWindow) {
        currentInfoWindow.close();
      }
      infoWindow.open(map, marker);
      currentInfoWindow = infoWindow;
    });
  });
}

Common Pitfalls & What to Check Next:

• API Key: Double-check that you have correctly included your Google Maps API key in the script tag. This is essential for the map to load.
• InfoWindow Closure: Always close the previous infoWindow before opening a new one to prevent multiple overlapping popups. The code above handles this correctly.
• Error Handling: Consider adding error handling to gracefully handle potential issues like network failures when loading the map or marker data.
• Marker Clustering: If you have a very large number of markers, consider using a marker clustering library to improve performance and visual clarity. Google Maps offers clustering options, or third-party libraries may also help.
• Map Styling: Explore the Google Maps API documentation to customize the appearance of your map (styles, controls, etc.).

Still running into issues? Share your (sanitized) config files, the exact command you ran, and any other relevant details. The community is here to help!

[mythicMuse]

This screams automation to me. Why manually code all those loops and event listeners when you can set up a workflow that handles the entire Google Maps integration automatically?

I’ve built similar location displays for our internal tools. The game changer was automating everything. Create a workflow that takes your location data, generates the markers, handles InfoWindow logic, and manages map styling - no JavaScript needed.

When your dataset changes or grows, everything updates automatically. No more debugging scope issues or InfoWindow closure problems. Plus you can connect it to databases, spreadsheets, or APIs without custom code.

For your case, the workflow would process your places array, create each marker with coordinates, set up click handlers for InfoWindows, and handle map initialization. Way cleaner than managing all that JavaScript manually.

Check out Latenode for this - it handles Google Maps integrations really well and saves tons of development time: https://latenode.com