public ApplicationViewModel( IViewModelDependencies appCtx, IZetboxContext dataCtx, ViewModel parent, Application app) : base(appCtx, dataCtx, parent) { if (app == null) throw new ArgumentNullException("app"); this.app = app; _wndMdlType = app.WorkspaceViewModel != null ? Type.GetType(app.WorkspaceViewModel.ViewModelTypeRef, true) : null; }