public PagoDevolucionViewModel() { if (!this.IsInDesignMode) { _proxy = CommonServiceLocator.ServiceLocator.Current.GetInstance <Common.ServiceContracts.IDataServiceAsync>(); } this.PropertyChanged += PagoDevolucionViewModel_PropertyChanged; this.FindCommand = new RelayCommand(async() => { this.IsBusy = true; this.Devolucion = await _proxy.FindDevolucionAsync(this.Sucursal, this.Folio); if (this.Devolucion != null) { if (this.Devolucion.Disponible >= this.Total) { this.Pagar = this.Total; } else if (this.Devolucion.Disponible > 0) { this.Pagar = this.Devolucion.Disponible; } } this.IsBusy = false; }, () => !String.IsNullOrEmpty(this.Sucursal) && !String.IsNullOrEmpty(this.Folio)); if (this.IsInDesignMode) { //this.Total = 123.4m; this.Pagar = 456; this.Sucursal = "01"; this.Folio = "123456"; this.Devolucion = new Common.Entities.Devolucion { Sucursal = "02", Folio = "000123", Disponible = 200m }; } }