Combining OpenLayers and Ext
For the last week I’ve been learning the Ext javascript framework and its really been a joy. Version 2.0 is very polished and it “just works”. I put together a very basic tool demo for Oregon Department of Fish and Wildlife and Alaska Department of Fish and Game that uses Ext for the layout, OpenLayers for the mapping component and Mapserver/PostGIS on the backend for serving up map tiles and doing spatial queries. The library is a beast but its everything you want in one place (think jQuery+Prototype+YUI).
Now to find a robust framework for the backend (I’m tired of PHP), maybe Pylons.
ODFW Demo - Try selecting the Coos Bay or Tillamook Bay Coho Population in the menu and then opening the Adult tab to view different metrics queried from the DB.
More tool are in the works, stay tuned.
February 15th, 2008 at 2:41 pm
Hi,
while your screenshots look great, it appears the ODFW link is down. I’m interested in the load-delay while Ext & Openlayers load, & would be grateful for a chance to see your “live” application.
cheers,
Ian.
February 21st, 2008 at 5:49 pm
Ian, thanks for the comment, the link has been updated. The map now works with IE too. This demo borrows from some of the work done by the mapfish project (www.mapfish.org). Just look at their complex layout example and you’ll see similarities.
This first demo can have a significant load time. To improve that you can use gzip compression on the server side. The Ext and openlayers libraries are reduced in size about 4 times. In addition you can take advantage of Ext X-Types for lazy loading of widgets in complex layouts.