void ViewModel_NavigationHandler(object sender, MainViewModel.PageNavigationEventArgs e) { if (e.Type == MainViewModel.PageNavigationEventArgs.EventType.Back) { e.Processed = true; var pg = new pageWelcome(ViewModel); ViewModel.Navigate(pg); } else if (e.Type == MainViewModel.PageNavigationEventArgs.EventType.GetBackButtonVisibleState) { e.Processed = true; e.Result = true; } }