private void Accept_Click(object sender, RoutedEventArgs e)
        {
            if ((formatTextBox.Text != specItem.format) |
                (zonaTextBox.Text != specItem.zona) |
                (positionTextBox.Text != specItem.quantity) |
                (oboznachenieTextBox.Text != specItem.note) |
                (nameTextBox.Text != specItem.quantity) |
                (quantityTextBox.Text != specItem.quantity) |
                (noteTextBox.Text != specItem.quantity))
            {
                specItem.format       = formatTextBox.Text;
                specItem.zona         = zonaTextBox.Text;
                specItem.position     = positionTextBox.Text;
                specItem.oboznachenie = oboznachenieTextBox.Text;
                specItem.name         = nameTextBox.Text;
                specItem.quantity     = quantityTextBox.Text;
                specItem.note         = noteTextBox.Text;

                project.AddSpecItem(specItem);

                this.DialogResult = true;
            }
        }