private void NavigateToViewMethod(string destination)
        {
            switch (destination)
            {
            case "SupplyDisplay":
                CurrentViewModel = new SupplyDisplayViewModel();
                break;

            case "SupplyReport":
                CurrentViewModel = new SupplyReportViewModel();
                break;

            default:
                break;
            }
        }
 public SupplyViewModel()
 {
     _currentViewModel = new SupplyDisplayViewModel();
 }