Update 2009/03/04: Here are 2 links that may help you with your understanding of MVVM
first 2 videos about implementing MVVM, one in WPF and the other in Silverlight http://weblogs.asp.net/craigshoemaker/archive/2009/02/26/hands-on-model-view-viewmodel-mvvm-for-silverlight-and-wpf.aspx and an article that delves into creating a fully functional app http://www.codeproject.com/KB/smart/Sonic.aspx
I attended a talk Jonas did last week on MVVM and it got me excited enough to explore it myself. His blog has a wealth of information, and it has all been summarised in his latest post. By reading his blog and many other bits and pieces around the web i was able to get this working myself. I’m going to put it all together into one blog post to give a complete look at how to incorporate all of it together. I aim to show how it all hooks in together and not just show a diagram saying that you should split things out.
Presumably you already have an idea of what Model/View/ViewModel is. The background and reasoning behind it is beyond the scope of this article, but here is an article I recommend. And also all of Jonas’s articles. But basically MVVM + Dependency injection allows your applications to be loosely coupled with the GREAT advantage that all of your code can now be unit tested, since the UI is just databinding to your classes.
The application is going to look like the diagram. It will be split up into the usual Model/View/ViewModel components, but I aim to show all of the supporting code that is needed to get it all working.
The application will be a HR system which just show a list of all the employees. I am just going to implement this single method to try and keep this example as simple as possible