protected function wizardAddProductClassField()
    {
        // Required
        $this->validatePrompt('product_class_id', $this->text('Product class'), 'product_class_field');
        $this->validatePrompt('field_id', $this->text('Field ID'), 'product_class_field');

        // Optional
        $this->validatePrompt('required', $this->text('Required'), 'product_class_field', 0);
        $this->validatePrompt('multiple', $this->text('Multiple'), 'product_class_field', 0);

        $this->validateComponent('product_class_field');
        $this->addProductClassField();
    }