DynamicMapServiceLayer render complete event for ArcGIS JavaScript Extension for Google Maps API

I’ve got a DynamicMapServiceLayer with 1000’s of features. So it takes a while to draw the overlay. This extra draw time justifies displaying a “loading” indicator image in the UI so as not to give the impression that the application has hung. So I searched for an event I could hook into to to get notification when all layers have finished drawing on the map. I tried the events on GMap2 (dragstart, dragend, movestart, moveend, zoomstart, zoomend), and while these let me know when to display my loading icon, they didn’t tell me when all layers had finished drawing. No luck. After pulling my hair out I got feedback from Praveenkumar Ponnusamy at ESRI.

ArcGIS JS Extension for Google Maps API v1.2

v1.2 will include a new event for the DynamicMapServiceLayer that you can wire up to get notification when the layer has finished drawing.

v1.2 is expected to be released around the end of October.

Update: v1.2 has been released and delivers with it Dojo v1.2. You may now listen and respond to the update event that has been added to DynamicMapServiceLayer, ImageServiceLayer, and TiledMapServiceLayer.

ArcGIS JS Extension for Google Maps API v1.1

In the meantime, here is a hack for v1.1. Note, this is NOT officially supported by ESRI and WILL NOT work at v1.2.

Download page sample

Code

<script type="text/javascript"> var gmap, dynamicMapServicelayer; function initialize() { //Load Google Maps gmap = new GMap2(document.getElementById("map_canvas")); gmap.addControl(new GLargeMapControl()); gmap.enableScrollWheelZoom(); gmap.setCenter( new GLatLng(36.62513340485903, -112.32421875), 3); addUpdateEventWorkaround(); //create dynamic map service layer dynamicMapServicelayer = new esri.arcgis.gmaps.DynamicMapServiceLayer( "http://sampleserver1.arcgisonline.com/ArcGIS/rest/services/" + "Specialty/ESRI_StatesCitiesRivers_USA/MapServer", null, 0.75, dynamicMapServiceLoaded); } function dynamicMapServiceLoaded(mapService) { gmap.addOverlay(dynamicMapServicelayer); } function addUpdateEventWorkaround() { /************************************************/ // !!!!!!!! ALERT: IMPORTANT NOTE !!!!!!!! // This workaround is NOT officially supported and WILL NOT work // at version 1.2 So, PLEASE include a FIXME note in your code to // remove this workaround once you start using version 1.2 /************************************************/ // save the original redraw handler var _redrawHandler = esri.arcgis.gmaps.DynamicMapServiceLayer.prototype._redrawHandler; // create a new method to handle layer redraw esri.arcgis.gmaps.DynamicMapServiceLayer.prototype._redrawHandler = function() { // setup listener for image load event var listener = GEvent.addDomListener(this._img_loading, "load", function() { GEvent.removeListener(listener); listener = null; GLog.write("Map image has been loaded"); // include code here to remove your "image loading" message }); // call the actual redraw handler _redrawHandler.apply(this, arguments); } } </script>

Thanks Praveenkumar!