Esri Leaflet

Styling clusters

Customizing the display of clusters and markers with L.DivIcon and L.MarkerClusterGroup options. More information about Feature Layers can be found in the L.esri.FeatureLayer documentation.

<html>
<head>
  <meta charset=utf-8 />
  <title>Styling clusters</title>
  <meta name='viewport' content='initial-scale=1,maximum-scale=1,user-scalable=no' />


  <!-- Load Leaflet from CDN-->
  <link rel="stylesheet" href="https://unpkg.com/leaflet@1.1.0/dist/leaflet.css"
    integrity="sha512-wcw6ts8Anuw10Mzh9Ytw4pylW8+NAD4ch3lqm9lzAsTxg0GFeJgoAtxuCLREZSC5lUXdVyo/7yfsqFjQ4S+aKw=="
    crossorigin=""/>
  <script src="https://unpkg.com/leaflet@1.1.0/dist/leaflet-src.js"
    integrity="sha384-TWB9xRHTlLQmqAngHwD7usGcf4akGf0JP6aHwlgilpmOu2UuBq5aWLsDAh39iSn1"
    crossorigin=""></script>


  <!-- Load Esri Leaflet from CDN -->
  <script src="https://unpkg.com/esri-leaflet@2.0.8"
    integrity="sha384-ze7rgny7/YGFxBlVgTBdOABNWe5V9BYjju/qwqJhCU8XJHtuEnRlbUpN5lXyY706"
    crossorigin=""></script>


  <style>
    body { margin:0; padding:0; }
    #map { position: absolute; top:0; bottom:0; right:0; left:0; }
  </style>
</head>
<body>

<link rel="stylesheet" type="text/css" href="https://unpkg.com/leaflet.markercluster@1.0.4/dist/MarkerCluster.Default.css">
<link rel="stylesheet" type="text/css" href="https://unpkg.com/leaflet.markercluster@1.0.4/dist/MarkerCluster.css">
<script src="https://unpkg.com/leaflet.markercluster@1.0.4/dist/leaflet.markercluster.js"></script>

<!-- Load Clustered Feature Layer from CDN -->
<script src="https://unpkg.com/esri-leaflet-cluster@2.0.0"></script>

<style>
  .cluster {
    background: #2d84c8;
    border-radius: 50%;
    text-align: center;
    color: white;
    font-weight: 700;
    border: 1px solid #2d84c8;
    font-family: monospace;
  }

  .cluster:before {
     content: ' ';
     position: absolute;
     border-radius: 50%;
     z-index: -1;
     top: 1px;
     left: 1px;
     right: 1px;
     bottom: 1px;
     border: 1px solid white;
  }

  .digits-1 {
    font-size: 14px;
    height: 28px;
    width: 28px;
    line-height: 28px;
    margin-top: -14px;
    margin-left: -14px;
  }

  .digits-2 {
    font-size: 16px;
    height: 34px;
    width: 34px;
    line-height: 35px;
    margin-top: -17px;
    margin-left: -17px;
  }

  .digits-2:before {
    border-width: 2px;
  }

  .digits-3 {
    font-size: 18px;
    height: 48px;
    width: 47px;
    line-height: 47px;
    border-width: 3px;
    margin-top: -24px;
    margin-left: -24px;
  }

  .digits-3:before {
    border-width: 3px;
  }

  .digits-4 {
    font-size: 18px;
    height: 58px;
    width: 58px;
    line-height: 57px;
    border-width: 4px;
    margin-top: -29px;
    margin-left: -29px;
  }

  .digits-4:before {
    border-width: 4px;
  }
</style>

<div id="map"></div>

<script>
  var map = L.map('map').setView([45.5276, -122.6674], 13);

  // Add ArcGIS Online basemap
  L.esri.basemapLayer('Gray').addTo(map);

  // Define some icons that represent our bus stops
  var icons = {
    north: L.icon({
      iconUrl: 'https://esri.github.io/esri-leaflet/img/bus-stop-north.png',
      iconRetinaUrl: 'https://esri.github.io/esri-leaflet/img/bus-stop-north@2x.png',
      iconSize: [27, 31],
      iconAnchor: [13.5, 17.5],
      popupAnchor: [0, -11],
    }),
    south: L.icon({
      iconUrl: 'https://esri.github.io/esri-leaflet/img/bus-stop-south.png',
      iconRetinaUrl: 'https://esri.github.io/esri-leaflet/img/bus-stop-south@2x.png',
      iconSize: [27, 31],
      iconAnchor: [13.5, 13.5],
      popupAnchor: [0, -11],
    }),
    east: L.icon({
      iconUrl: 'https://esri.github.io/esri-leaflet/img/bus-stop-east.png',
      iconRetinaUrl: 'https://esri.github.io/esri-leaflet/img/bus-stop-east@2x.png',
      iconSize: [31, 27],
      iconAnchor: [13.5, 17.5],
      popupAnchor: [0, -11],
    }),
    west: L.icon({
      iconUrl: 'https://esri.github.io/esri-leaflet/img/bus-stop-west.png',
      iconRetinaUrl: 'https://esri.github.io/esri-leaflet/img/bus-stop-west@2x.png',
      iconSize: [31, 27],
      iconAnchor: [17.5, 13.5],
      popupAnchor: [0, -11],
    }),
  };

  // create a new cluster layer (new syntax at 2.0.0)
  var stops = L.esri.Cluster.featureLayer({
    url: 'https://services.arcgis.com/rOo16HdIMeOBI4Mb/arcgis/rest/services/stops/FeatureServer/0',
    spiderfyOnMaxZoom:false,
    disableClusteringAtZoom: 16,
    polygonOptions: {
      color: '#2d84c8',
      weight: 4,
      opacity: 1,
      fillOpacity: 0.5
    },
    // this function defines how the icons
    // representing  clusters are created
    iconCreateFunction: function(cluster) {
      // get the number of items in the cluster
      var count = cluster.getChildCount();

      // figure out how many digits long the number is
      var digits = (count+'').length;

      // return a new L.DivIcon with our classes so we can
      // style them with CSS. Take a look at the CSS in
      // the <head> to see these styles. You have to set
      // iconSize to null if you want to use CSS to set the
      // width and height.
      return new L.divIcon({
        html: count,
        className:'cluster digits-'+digits,
        iconSize: null
      });
    },

    // this function defines how individual markers
    // are created. You can see we are using the
    // direction from the feature to get the icon
    pointToLayer: function (geojson, latlng) {
      var direction = (geojson.properties.direction) ? geojson.properties.direction.toLowerCase() : 'none';
      return L.marker(latlng, {
        icon: icons[direction]
      });
    }
  }).addTo(map);

  stops.bindPopup(function(feature){
    return L.Util.template('<strong>{stop_name}</strong><br>{stop_desc}', feature.properties);
  });
</script>

</body>
</html>

Edit this sample on GitHub

Esri Leaflet is a project from the Esri PDX R&D Center and the Esri Community