Question

I have what I believe to be very simple code. I draw a polygon, a marker and then throw an alert if the point I have hard-coded is within the polygon. Yet when I run this I get an ‘Uncaught TypeError: Cannot call method 'lng' of undefined‘ error in the console.

My code is as follows:

   function initialize() {


        var mapOptions = {
          center: new google.maps.LatLng(38.990842,-76.93625),
          zoom: 17,
          mapTypeId: google.maps.MapTypeId.ROADMAP
        };
        var map = new google.maps.Map(document.getElementById("map_canvas"),
            mapOptions);

      var box = [new google.maps.LatLng(38.9913160,-76.937079),
      new google.maps.LatLng(38.991333,-76.936119),
      new google.maps.LatLng(38.990287, -76.936108),
      new google.maps.LatLng(38.990278,-76.937057),
      new google.maps.LatLng(38.990495,-76.937052),
      new google.maps.LatLng(38.990499,-76.936424),
      new google.maps.LatLng(38.991091,-76.93643),
      new google.maps.LatLng(38.991104,-76.937079)
      ];

        var mPoint = [new google.maps.LatLng(38.991300,-76.936165)];
  var marker = new google.maps.Marker({
    map: map, 
    position: new google.maps.LatLng(38.991300,-76.936165),
    //position: new google.maps.LatLng(mPoint),
    draggable: true
  });

        var AVpoly = new google.maps.Polygon({path:box,
  strokeColor:"#0000FF",
  strokeOpacity:0.8,
  strokeWeight:2,
  fillColor:"#0000FF",
  fillOpacity:0.4});

      AVpoly.setMap(map);
marker.setMap(map);
if(google.maps.geometry.poly.containsLocation(google.maps.LatLng(38.990842,-76.93625), box) == true) {
 alert("yes");
}

      }

I cannot see anything wrong with this nor do I see why the alert if not firing. I did even change it to false in the off-chance my geometry was wrong….

Answer 1

Box is not a google.maps.Polygon; it is an array of google.maps.LatLng objects. Use AVpoly instead (the documentation specifies the second argument is a Polygon).

That doesn’t work, you are also missing the “new” for the google.maps.LatLng constructor. This does work (using the marker.getPosition method which returns a google.maps.LatLng):

var marker = new google.maps.Marker({
    map: map, 
    position: new google.maps.LatLng(38.991300,-76.936165),
    draggable: true
  });

var AVpoly = new google.maps.Polygon({path:box,
    map: map, 
  strokeColor:"#0000FF",
  strokeOpacity:0.8,
  strokeWeight:2,
  fillColor:"#0000FF",
  fillOpacity:0.4});

  if(google.maps.geometry.poly.containsLocation(marker.getPosition(), AVpoly) == true) {
    alert("yes");
 }

Working (if annoying) example