today's lesson:
one does not simply open a new window with mvvm pattern

Can you elaborate?

@nblackburn i've got a gridview. when a row is double clicked - a window should open with details. cannot do it in the viewmodel cause it would break the pattern. i ended up firing an event in the viewmodel like "OnDetailRequesting" on which the codebehind if the view is listening and then instantiates the detail window

Doing WPF I see, unfortunately I stopped doing Windows development at the time I was learning mvvm, might get back on that soon though.
But I recall there was an mvvm framework that helps by using Command class with, umm ... Don't recall lol

@gitpush thats right there are frameworks. but as far as i know they are all breaking the pattern

@nebula I see, I'm sorry I can't help out I stopped at the basics of MVVM