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javascriptgoogle-mapsgoogle-maps-api-3geojson

Removing outline and increasing opacity in GeoJSON drawn polygons on Google Maps API

I am working on something that leverages the Google Maps API to draw n number of polygons using GeoJSON. I was successful in drawing it, but I also want to increase the opacity of the polygons drawn, as well as remove an ugly outline on each of the polygons.

I looked through the documentation on the Google Maps API here, but it only tells you how to load the GeoJSON file, not modify traits of the drawn polygons.

map.data.loadGeoJson('google.json');

That up there is how you load the GeoJSON and the only command that you can use. I know it seems that I haven't tried anything, but I have and none of it's substantial enough to include in this question.

So my question is - How do you remove the outline from GeoJSON drawn images and also increase the opacity?

Below is also an image of what it currently looks like:

Image of what it currently looks like

Solution

  • use fillOpacity: 1 and strokeWeight: 0 in style options

    https://plnkr.co/edit/puMK8mAskLiaExmNKIEI?p=preview

    <!DOCTYPE html>
<html>
  <head>
    <title>Data Layer: Styling</title>
    <meta name="viewport" content="initial-scale=1.0">
    <meta charset="utf-8">
    <style>
      /* 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;
      }
    </style>
  </head>
  <body>
    <div id="map"></div>
    <script>

      var map;
      function initMap() {
        map = new google.maps.Map(document.getElementById('map'), {
          zoom: 4,
          center: {lat: -28, lng: 137}
        });

        // Load GeoJSON.
        map.data.loadGeoJson(
            'https://storage.googleapis.com/mapsdevsite/json/google.json');

        // Set the stroke width, and fill color for each polygon
        map.data.setStyle(function(feature) {
          var color = feature.getProperty('color');
          return {
            fillColor: color,
            fillOpacity: 1,
            strokeWeight: 0
          };
        });
      }
    </script>
    <script async defer
    src="https://maps.googleapis.com/maps/api/js?callback=initMap">
    </script>
  </body>
</html>