MVVM: Binding to Model while keeping Model in sync with a server version

I've spent quite some time to try and find an elegant solution for the following challenge. I've been unable to find a solution that's more than a hack around the problem.

I've got a simple setup of a View, ViewModel and a Model. I will keep it very simple for the sake of explanation.

• The Model has a single property called Title of type String.
• The Model is the DataContext for the View.
• The View has a TextBlock thats databound to Title on the Model.
• The ViewModel has a method called Save() that will save the Model to a Server
• The Server can push changes made to the Model

So far so good. Now there are two adjustments I need to make in order to keep the Model in sync with a Server. The type of server is not important. Just know that I need to call Save() in order to push the Model to the Server.

Adjustment 1:

• The Model.Title property will need to call RaisePropertyChanged() in order to translate changes made to the Model by the Server to the View. This works nicely since the Model is the DataContext for the View

Not too bad.

Adjustment 2:

• Next step is to call Save() to save changes made from the View to the Model on the Server. This is where I get stuck. I can handle the Model.PropertyChanged event on the ViewModel that calls Save() when the Model gets changed but this makes it echo changes made by the Server.

I'm looking for an elegant and logical solution and am willing to change my architecture if it makes sens