public IResult EnterCatalog() { if (CurrentCatalog == null) { return(null); } if (ParentModel.Mode == CatalogViewMode.Basic) { if (!CurrentCatalog.HaveOffers) { return(new ShowPopupResult(() => ParentModel.ShowOrderHistory())); } Shell.Navigate(new CatalogOfferViewModel(CurrentCatalog)); } else if (ParentModel.Mode == CatalogViewMode.CatalogSelector) { ParentModel.CatalogSelector(CurrentCatalog); } return(null); }