public void HandleUserInteraction(object sender, CalculatorView.UserInteractionArgs args) { switch (args.Type) { case CalculatorView.UserInteractionArgs.Kind.Eq: model.Execute(); break; case CalculatorView.UserInteractionArgs.Kind.Num: model.Append(args.Value); break; case CalculatorView.UserInteractionArgs.Kind.Op: model.Operation = args.Value; break; case CalculatorView.UserInteractionArgs.Kind.ClearAll: model.ClearAll(); break; case CalculatorView.UserInteractionArgs.Kind.Clear: model.Clear(); break; case CalculatorView.UserInteractionArgs.Kind.Bsp: model.Bsp(); break; case CalculatorView.UserInteractionArgs.Kind.Negate: model.Negate(); break; } Refresh(); }