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MVVM Model - Need a hint

Posted By:      Posted Date: September 20, 2010    Points: 0   Category :WPF


I started a projects management application by using the MVVM model. I have a "MasterViewModel" which contains the "ObservableCollection" and the "ICollectionView" as well as some Commands. Everything works fine and I have a listbox that shows all the active projects in my database, which are bound through an ObservableCollection<ProjectViewModel>.

I based everything on an example MVVM implementation I found on the internet (http://japf.developpez.com/tutoriels/dotnet/mvvm-pour-des-applications-wpf-bien-architecturees-et-testables/ - it's in french, but you can download the app in section VII). That program is a simple "Persons" database which shows the name and gender.

However my application is a little more complex and I have several layers of "databases". Basically, each project contains a list of languages, each language contains a list of milestones, and each milestone contains a list of assets (such as hardware or workforce needed at that moment of the year). I would like to know the best approach to tackle on this solution: should I implement all views in my "MasterViewModel" class, or should I split it up in several layers?

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