private async void BtnSubmit_Click(object sender, RoutedEventArgs e) { if (_isMajor) { if (AppState.AllCategories.All(category => category.Name != TxtName.Text)) { if (await AppState.AddCategory(_majorCategory, TxtName.Text, _isMajor)) { ClosePage(); } } } else { if (!_majorCategory.MinorCategories.Contains(TxtName.Text)) { if (await AppState.AddCategory(_majorCategory, TxtName.Text, _isMajor)) { ClosePage(); } } } }