public BestellpositionDialog(bestellposition p) : this()
        {
            var repo = new BestellPositionRepository();

            p = repo.GetSingle(p.Id); // reload, so we have every assoc loaded now

            _viewModel  = BestellpositionViewModel.FromExisting(p);
            DataContext = _viewModel;
        }
 public BestellpositionDialog(bestellung b) : this()
 {
     _viewModel  = BestellpositionViewModel.FromBestellung(b);
     DataContext = _viewModel;
 }