The Screen derived instances I want to handle the I way I described above, are always created using the WindowManager. So their parent "pseudo-Conductor" should always be the the windowmanager itself.
Anyway I implemented it the way you suggested but the window is not refocused:
publicvoid OpenOrReactivateSubView() { if (this.subViewModel == null) { this.subViewModel = new SubViewModel(); } if (this.subViewModel.IsActive) { ((IDeactivate)this.subViewModel).Deactivate(false); ((IActivate)this.subViewModel).Activate(); return; } this.windowManager.ShowWindow(this.subViewModel); }