Question

I’m back with more work on the Google Map that I’ve been working on. Here is the situation:

I have a map of Virginia. It will have markers in it, but I need the markers to be added/removed/editable by several people. As a result, I created a Google map in “My Places” and I’m importing the resulting KML file into a map I’m loading into the API.

I’m also trying to “white out” neighboring states by drawing a polygon over them and adding a white layer over them with 75% opacity, in order to make the state of Virginia stand out more.

However, I’ve run into a problem where if a marker from the KML layer “overlaps” onto the polygon covering a bordering state, the opaque polygon covers the layer AND the marker becomes unclickable. If one zooms in enough, one can click the marker, but I want people to be able to click the marker from the original zoom.

I’ve tried making the markers first, then adding the KML, and doing the KML first then drawing the polygons, but it doesn’t seem to matter. I even tried a variation of the solution here: Handle when drawing of polygons is complete in google maps api v3 where I put the trigger to add the KML layer inside of the listener event, but still no dice.

My searching on Google also hasn’t led me to anything that looks useful. I don’t know if this is still a problem with the order the layers are being ordered, or if polygons somehow “override” a KML layer, regardless of the order, or if there is some way to explicitly tell the KML markers to stay on top of the polygons.

First off, here is the main code I’m using to draw the layers right now:

function initialize() {
  var mapOptions = {
    zoom: 7,
    center: new google.maps.LatLng(38, -79.5),
    disableDefaultUI: true,
    mapTypeId: google.maps.MapTypeId.TERRAIN
  }
  var map = new google.maps.Map(document.getElementById("map_canvas"), mapOptions);

  borderingStates(map);

  var participantsLayer = new google.maps.KmlLayer('https://maps.google.com/maps/ms?msa=0&msid=204048902337864904598.0004cc332e8034251c1db&ie=UTF8&ll=37.668046,-80.289717&spn=1.959603,5.642338&output=kml',{preserveViewport:true});

  google.maps.event.addListener(map,'idle', function() {
  participantsLayer.setMap(map);
 });

}

function loadScript() {
  var script = document.createElement("script");
  script.type = "text/javascript";
  script.src = "https://maps.googleapis.com/maps/api/js?key=abc.def&sensor=false&callback=initialize";
  document.body.appendChild(script);
}

window.onload = loadScript;

Next, here is an example of the code I’m using to draw the polygons. This happens when I call the borderingStates function above:

//Delaware
 DEpoints = [

new google.maps.LatLng(39.7188, -75.7919),
new google.maps.LatLng(39.5210, -75.7837),
...
new google.maps.LatLng(39.8296, -75.6477),
new google.maps.LatLng(39.7199, -75.7906)
];

  // Construct the polygon
  var Delaware = new google.maps.Polygon({
    paths: DEpoints,
    fillColor: invisColor,
    strokeOpacity: 0,
    fillOpacity: .75
  });

  Delaware.setMap(map);

And then I repeat that for each state I draw a polygon for – I think there are 6 or 7.

I can’t tell that there is anything in particular about the code that wouldn’t cause it to work other than perhaps how Google Maps inherently treats polygons and KML Layers.

Answer 1

I would suggest making your polygons with KmlLayer (or FusionTablesLayer) as well.
You can control the ordering of layers by the order that you add them to the map (first one is on the bottom). I believe native Google Maps API v3 Polygons will always appear above layers. Your other option would be to make the Polygons “unclickable” (clickable: false) [not sure if this will work or not].