protected VM PrepareViewModel <VM>(Func <VM> instantiation) where VM : IViewModel
        {
            VM vm = instantiation.Invoke();

            ViewModelResolver.BuildUp(vm);

            return(vm);
        }
        protected VM PrepareViewModel <VM>() where VM : IViewModel, new()
        {
            VM vm = Activator.CreateInstance <VM>();

            ViewModelResolver.BuildUp(vm);

            return(vm);
        }