cluster markers to handle larger datasets

src/view.map.js

@@ -53,12 +53,22 @@ my.Map = Backbone.View.extend({
         geomField: null,
         lonField: null,
         latField: null,
-        autoZoom: true
+        autoZoom: true,
+        cluster: true
       },
       options.state
     );
     this.state = new recline.Model.ObjectState(stateData);
 
+    this._clusterOptions = {
+      zoomToBoundsOnClick: true,
+      //disableClusteringAtZoom: 10,
+      maxClusterRadius: 80,
+      singleMarkerMode: false,
+      skipDuplicateAddTesting: true,
+      animateAddingMarkers: false
+    };
+
     // Listen to changes in the fields
     this.model.fields.bind('change', function() {
       self._setupGeometryField();
@@ -146,8 +156,11 @@ my.Map = Backbone.View.extend({
     }
 
     if (this._geomReady() && this.mapReady){
-      if (action == 'reset' || action == 'refresh'){
+      if (action == 'refresh' || action == 'reset') {
         this.features.clearLayers();
+        // recreate cluster group because of issues with clearLayer
+        this.map.removeLayer(this.markers);
+        this.markers = new L.MarkerClusterGroup(this._clusterOptions);
         this._add(this.model.records.models);
       } else if (action == 'add' && doc){
         this._add(doc);
@@ -161,6 +174,13 @@ my.Map = Backbone.View.extend({
           this._zoomPending = true;
         }
       }
+      this.map.removeLayer(this.features);
+      this.map.removeLayer(this.markers);
+      if (this.state.get('cluster')) {
+        this.map.addLayer(this.markers);
+      } else {
+        this.map.addLayer(this.features);
+      }
     }
   },
 
@@ -198,6 +218,9 @@ my.Map = Backbone.View.extend({
 
     if (!(docs instanceof Array)) docs = [docs];
 
+    // removing ad re-adding the layer enables faster bulk loading
+    self.map.removeLayer(self.markers);
+
     var count = 0;
     var wrongSoFar = 0;
     _.every(docs, function(doc){
@@ -236,9 +259,11 @@ my.Map = Backbone.View.extend({
       }
       return true;
     });
+
+    self.map.addLayer(self.markers);
   },
 
-  // Private: Remove one or n features to the map
+  // Private: Remove one or n features from the map
   //
   _remove: function(docs){
 
@@ -347,7 +372,7 @@ my.Map = Backbone.View.extend({
   //
   _zoomToFeatures: function(){
     var bounds = this.features.getBounds();
-    if (bounds.getNorthEast()){
+    if (bounds && bounds.getNorthEast() && bounds.getSouthWest()){
       this.map.fitBounds(bounds);
     } else {
       this.map.setView([0, 0], 2);
@@ -360,15 +385,27 @@ my.Map = Backbone.View.extend({
   // on [OpenStreetMap](http://openstreetmap.org).
   //
   _setupMap: function(){
+    var self = this;
     this.map = new L.Map(this.$map.get(0));
 
     var mapUrl = "http://otile{s}.mqcdn.com/tiles/1.0.0/osm/{z}/{x}/{y}.png";
     var osmAttribution = 'Map data &copy; 2011 OpenStreetMap contributors, Tiles Courtesy of <a href="http://www.mapquest.com/" target="_blank">MapQuest</a> <img src="http://developer.mapquest.com/content/osm/mq_logo.png">';
-    var bg = new L.TileLayer(mapUrl, {maxZoom: 18, attribution: osmAttribution ,subdomains: '1234'});
+    var bg = new L.TileLayer(mapUrl, {maxZoom: 18, attribution: osmAttribution ,subdomains: '1234'}).addTo(this.map);
-    this.map.addLayer(bg);
 
-    this.features = new L.GeoJSON();
+    this.markers = new L.MarkerClusterGroup(this._clusterOptions);
-    this.map.addLayer(this.features);
+
+    m = this.map;
+    l = this.markers;
+
+    this.features = new L.GeoJSON(null,{
+        pointToLayer: function (feature, latlng) {
+          var marker = new L.marker(latlng);
+          self.markers.addLayer(marker);
+          return marker;
+        }
+    });
+    //this.map.addLayer(this.features);
+    //this.map.addLayer(this.markers);
 
     this.map.setView([0, 0], 2);
 
@@ -441,8 +478,11 @@ my.MapMenu = Backbone.View.extend({
       </div> \
       <div class="editor-options" > \
         <label class="checkbox"> \
-          <input type="checkbox" id="editor-auto-zoom" checked="checked" /> \
+          <input type="checkbox" id="editor-auto-zoom" value="autozoom" checked="checked" /> \
           Auto zoom to features</label> \
+        <label class="checkbox"> \
+          <input type="checkbox" id="editor-cluster" value="cluster" checked="checked" /> \
+          Cluster markers</label> \
       </div> \
       <input type="hidden" class="editor-id" value="map-1" /> \
       </div> \
@@ -453,7 +493,8 @@ my.MapMenu = Backbone.View.extend({
   events: {
     'click .editor-update-map': 'onEditorSubmit',
     'change .editor-field-type': 'onFieldTypeChange',
-    'click #editor-auto-zoom': 'onAutoZoomChange'
+    'click #editor-auto-zoom': 'onAutoZoomChange',
+    'click #editor-cluster': 'onClusteringChange'
   },
 
   initialize: function(options) {
@@ -486,10 +527,14 @@ my.MapMenu = Backbone.View.extend({
     }
     if (this.state.get('autoZoom')) {
       this.el.find('#editor-auto-zoom').attr('checked', 'checked');
-    }
+    } else {
-    else {
       this.el.find('#editor-auto-zoom').removeAttr('checked');
     }
+    if (this.state.get('cluster')) {
+      this.el.find('#editor-cluster').attr('checked', 'checked');
+    } else {
+      this.el.find('#editor-cluster').removeAttr('checked');
+    }
     return this;
   },
 
@@ -540,6 +585,10 @@ my.MapMenu = Backbone.View.extend({
     this.state.set({autoZoom: !this.state.get('autoZoom')});
   },
 
+  onClusteringChange: function(e){
+    this.state.set({cluster: !this.state.get('cluster')});
+  },
+
   // Private: Helper function to select an option from a select list
   //
   _selectOption: function(id,value){

test/index.html

@@ -15,6 +15,7 @@
   <script type="text/javascript" src="../vendor/mustache/0.5.0-dev/mustache.js"></script>
   <script type="text/javascript" src="../vendor/bootstrap/2.0.2/bootstrap.js"></script>
   <script type="text/javascript" src="../vendor/leaflet/0.4.4/leaflet-src.js"></script>
+  <script type="text/javascript" src="../vendor/leaflet.markercluster/leaflet.markercluster.js"></script>
   <script type="text/javascript" src="../vendor/slickgrid/2.0.1/jquery-ui-1.8.16.custom.min.js"></script>
   <script type="text/javascript" src="../vendor/slickgrid/2.0.1/jquery.event.drag-2.0.min.js"></script>
   <script type="text/javascript" src="../vendor/slickgrid/2.0.1/slick.grid.min.js"></script>