public Step14Presenter(ContentControl groupBox)
        {
            _groupBox = groupBox;

            _material = _groupBox.Material();
            _table = _looseMdb.Reader.FetchTable(_material.ToTableName());

            _boxes = _groupBox.FindVisualChild<TextBox>().ToList();
            _comboBox = _groupBox.FindVisualChild<ComboBox>().SingleOrDefault();

            try
            {
                ValidateData();
                InitializeVariants();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.ToString(), "Exception", MessageBoxButton.OK, MessageBoxImage.Error);
            }
        }