Reverse Geocoding

by Diana Lemen

HTML

<div id="floating-panel">
  <input id="latlng" type="text" value="40.714224,-73.961452">
  <input id="submit" type="button" value="Reverse Geocode">
</div>
<div id="map"></div>
 <!-- Replace the value of the key parameter with your own API key. -->
<script async defer
src="https://maps.googleapis.com/maps/api/js?key=AIzaSyCkUOdZ5y7hMm0yrcCQoCvLwzdM6M8s5qk&callback=initMap">
</script>

CSS

/* Always set the map height explicitly to define the size of the div
 * element that contains the map. */
#map {
  height: 100%;
}
/* Optional: Makes the sample page fill the window. */
html, body {
  height: 100%;
  margin: 0;
  padding: 0;
}
#floating-panel {
  position: absolute;
  top: 10px;
  left: 25%;
  z-index: 5;
  background-color: #fff;
  padding: 5px;
  border: 1px solid #999;
  text-align: center;
  font-family: 'Roboto','sans-serif';
  line-height: 30px;
  padding-left: 10px;
}
#floating-panel {
  position: absolute;
  top: 5px;
  left: 50%;
  margin-left: -180px;
  width: 350px;
  z-index: 5;
  background-color: #fff;
  padding: 5px;
  border: 1px solid #999;
}
#latlng {
  width: 225px;
}

JavaScript

let latLng;
function initMap() {
  var map = new google.maps.Map(document.getElementById('map'), {
    zoom: 8,
    center: {lat: 40.731, lng: -73.997}
  });
  var geocoder = new google.maps.Geocoder;
  var infowindow = new google.maps.InfoWindow;

  document.getElementById('submit').addEventListener('click', function() {
    geocodeLatLng(geocoder, map, infowindow);
  });
 google.maps.event.addListener(map, 'click', function(e) {
 if(e){
 latLng = {
 lat: e.latLng.lat(),
 lng: e.latLng.lng()
 };
 }
  })
}

function geocodeLatLng(geocoder, map, infowindow) {
  var input = document.getElementById('latlng').value;
  var latlngStr = input.split(',', 2);
  var latlng = latLng;
  geocoder.geocode({'location': latlng}, function(results, status) {
    if (status === 'OK') {
      if (results[1]) {
        map.setZoom(11);
        var marker = new google.maps.Marker({
          position: latlng,
          map: map
        });
        infowindow.setContent(results[1].formatted_address +" "+ latlng.lat.toString() +" "+ latlng.lng.toString());
        infowindow.open(map, marker);
      } else {
        window.alert('No results found');
      }
    } else {
      window.alert('Geocoder failed due to: ' + status);
    }
  });
}