How to open a new window using MVVM Light Toolkit

Question

I am using MVVM Light toolkit in my WPF application. I would like to know what is the best approach for opening a new window from an existing window. I have got this M

Answer 1

You can abstract the view specific features into services using generic interface. In the view layer you can provide concrete instances of these services and build view models using the IoC container and Dependency Injection technique.

In your case you can build an interface IWindowManager or something similar which has the required method. This can be implmented in your view layer. I wrote a small blog post recently demonstrating how to abstract the dialog behaviour out of view model. Similar apporach can be used for any user interface related service like Navigation, MessageBoxes etc.

This link might be helpful for you http://nileshgule.blogspot.com/2011/05/silverlight-use-dialogservice-to.html

Many people also use the approach of firing events from view models which are subscribed on the view.cs file and from there the MessageBox or any other UI related action is performed. I personally like the approach of injecting services because then you can provide multiple implementations of the same service. A simple example would be how navigation is handled in Silverlight and Windows Phone 7 applications. You can use the same view model but inject different implementations of the Navigation service based on the application type.