mvvm - Best practice for calling View from ViewModel in WPF

Question

I am looking for an little example of wpf project where contains a best practice to navigate between views. Maybe with the framework MVVM Light and a NavigationService or ServiceLocator. Instead of calling View from ViewModel, how do you do that? How is your approach? Do you have a project example?

Answer 1

I prefer ViewModel first approach. That means navigation service take viewmodel as a parameter and then, based on naming convention, instance of view is created and loaded into frame.

navigationService.Navigate<SomePageViewModel>()

This has couple of advantages over URI based navigation, which is view first approach:

• Better testability
• possibility of dependency injection into view
• most important: Better maintability. If you rename or move your pages, this will won't compile until you fix it, unlike URIs. Uri's would throw error at runtime

Unfortunelly, I can't give you mine example project right now, but it's quite easy to implement your own