refreshing marker position every 5 seconds in google maps JavaScript API

Question

      setInterval(function () {initMap();},5000);
       //setInterval(function () {changeMarkerPosition(marker);},5000);
          var map;

          function initMap() {
            var lat = document.getElementById( 'lat' ).value;
            var lng = document.getElementById( 'lng' ).value;

            map = new google.maps.Map(
                document.getElementById('map'),
                {center: new google.maps.LatLng(lat, lng), zoom: 16});

            var iconBase =
                'https://developers.google.com/maps/documentation/javascript/examples/full/images/';

            var icons = {
              parking: {
                icon: iconBase + 'parking_lot_maps.png'
              },
              library: {
                icon: iconBase + 'library_maps.png'
              },
              info: {
                icon: iconBase + 'info-i_maps.png'
              }
            };

            var features = [
              {
                position: new google.maps.LatLng(lat, lng),
                type: 'info'
              },
            ];

            // Create markers in the map.
            for (var i = 0; i < features.length; i++) {
              var marker = new google.maps.Marker({
                position: features[i].position,
                icon: icons[features[i].type].icon,
                map: map
              });
            };
          }

This is my code which refreshes the whole map every 5 seconds instead i want to refresh the marker position every 5 seconds as i am getting the latitude and longitude from two input fields which are updating continuously

Answer 1

Please note that every time you call google.maps.Map() class, you are creating one Map Load which is billed as Dynamic Maps SKU . Instead of creating a map load every 5 seconds just to update the marker position, you can leverage the setPosition method of the google.maps.Marker class .

Here is a sample code where I am changing the markers position using the setPosition every 5 seconds.

Here is the breakdown of the code:

This is where I set the marker's initial position

 marker = new google.maps.Marker({
        position: myLatLng,
        map: map,
        title: 'Hello World!'
    });

This is the array of my coordinates where my markers should change position to:

    markerList = [
        [-33.950198, 151.259302],
        [-33.923036, 151.259052],
        [-34.028249, 151.157507],
        [-33.80010128657071, 151.28747820854187]
    ];

I then used a for loop to go through all the coordinates in the array. Then put the setTimeout to put 5 seconds interval when changing the marker position:

for (var i = 0; i < markerList.length; i++) {
        (function(index) {
            setTimeout(function() {
                marker.setPosition(new google.maps.LatLng(markerList[index][0], markerList[index][1]));
            }, i * 5000);
        })(i);
    }

Hope this helps!