protected void UpdateState()
{
bool isValid = validator.IsAttributeValid(element, attrName, element.GetAttributeNode(attrName));
label.ForeColor = isValid ? Color.Black : Color.Red;
label.Font = requiredAttribute || !isValid ? new Font(Font, FontStyle.Bold) : Font;
XmlAttribute a = element.GetAttributeNode(attrName);
deleteButton.Visible = (a != null && a.Specified);
}