MVVM: Thin ViewModels and Rich Models

Question

I\'m continuing to struggle with the MVVM pattern and, in attempting to create a practical design for a small/medium project, have run into a number of challenges. One of t

Answer 1

I consider this to be the pragmatic approach - we have followed this pattern successfully in the past.

The basic premis was to bind directly to a model that implements INotifyPropertyChanged for most read-only data, and then add extra properties to the viewmodel for view specific stuff that needs to be transformed (as you suggested). For non read-only properties, we found it easiest the create viewmodel entries (generally of type string) as this allows client-side validation to be added easily in the viewmodel.