Fusion is incredibly flexible and cool technology for building web mapping applications. It is also very new technology with limited documentation, leaving more than a few people wondering how to figure it out.
Not to worry, help is on the way! 
With the MapGuide Open Source 2.0 Beta2 release, a bit of documentation for Fusion was quietly placed in the MapGuide section of the OSGeo download server.
These docs are still a bit “beta” (ie. incomplete), but there is some good information in there for anyone looking to get their feet wet with Fusion. I would suggest ignoring the “Installing and Configuring” doc. Start with “Introduction” (briefly), go on to “Generic Web Mapping Application Components”, then “Widget Concepts”, and finally “Create A Basic Web Mapping Application”.
Apart from the documentation, there is also a new template called “learn” included in the Beta2 installer. Look familiar?
That’s right, this looks a LOT like the existing “AJAX” viewer. Although it isn’t as fancy as the fusion templates that I posted about previously, it does have a lot of functionality. Fortunately, it is absolutely riddled with comments, and is a lot easier to reverse-engineer. It is a good starting point for beginning to understand some of the more involved Jx layout capabilities, advanced widgets, etc. You can find it in the MapGuide install directory, under
WebServerExtensions/www/fusion/templates/mapguide/learn/.
If you are looking for something more bite-sized to get started with, you might also find this small code sample useful:
http://trac.osgeo.org/mapguide/wiki/CodeSamples/Fusion/SuperSimple
This gives you an _extremely_ basic application that uses a few lines of straight HTML/CSS/XML and no JavaScript other than what Fusion loads itself. I obviously didn’t take too much time to make it look pretty:
I have high hopes that the Fusion documentation will be considerably more complete before MapGuide Open Source 2.0 is released, but now early adopters have something to play with.
If you haven’t downloaded the latest beta, please help us to make it better by trying it out and reporting any problems.
-J
