Drawing tools

by Lawrence Ross

HTML

<input id="save" value="save" type="button" />
<div id="map"></div>
<div id="geojson"></div>
<!-- Replace the value of the key parameter with your own API key. -->
<script src="https://maps.googleapis.com/maps/api/js?libraries=drawing&callback=initMap&key=AIzaSyCkUOdZ5y7hMm0yrcCQoCvLwzdM6M8s5qk" async defer></script>

CSS

html,
body {
  height: 100%;
  margin: 0;
  padding: 0;
}

#map {
  height: 100%;
}

JavaScript

// This example requires the Drawing library. Include the libraries=drawing
// parameter when you first load the API. For example:
// <script src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&libraries=drawing">

function initMap() {
  var map = new google.maps.Map(document.getElementById('map'), {
    center: {
      lat: -34.397,
      lng: 150.644
    },
    zoom: 8
  });

  var drawingManager = new google.maps.drawing.DrawingManager({
    drawingMode: google.maps.drawing.OverlayType.MARKER,
    drawingControl: true,
    drawingControlOptions: {
      position: google.maps.ControlPosition.TOP_CENTER,
      drawingModes: [
        google.maps.drawing.OverlayType.MARKER,
        google.maps.drawing.OverlayType.CIRCLE,
        google.maps.drawing.OverlayType.POLYGON,
        google.maps.drawing.OverlayType.POLYLINE,
        google.maps.drawing.OverlayType.RECTANGLE
      ]
    },
    markerOptions: {
      icon: 'https://developers.google.com/maps/documentation/javascript/examples/full/images/beachflag.png'
    },
    circleOptions: {
      fillColor: '#ffff00',
      fillOpacity: 1,
      strokeWeight: 5,
      clickable: false,
      editable: true,
      zIndex: 1
    }
  });
  drawingManager.setMap(map);
  var dataLayer = new google.maps.Data();

  // from http://stackoverflow.com/questions/25072069/export-geojson-data-from-google-maps
  // from http://jsfiddle.net/doktormolle/5F88D/
  google.maps.event.addListener(drawingManager, 'overlaycomplete', function(event) {
    switch (event.type) {
      case google.maps.drawing.OverlayType.MARKER:
        dataLayer.add(new google.maps.Data.Feature({
          geometry: new google.maps.Data.Point(event.overlay.getPosition())
        }));
        break;
      case google.maps.drawing.OverlayType.RECTANGLE:
        var b = event.overlay.getBounds(),
          p = [b.getSouthWest(), {
            lat: b.getSouthWest().lat(),
            lng: b.getNorthEast().lng()
          }, b.getNorthEast(), {
         ...