TThemedHeader describes the possible themable parts of a header control.

TThemedHeader = (
  thHeaderDontCare,
  thHeaderRoot,
  thHeaderItemNormal,
  thHeaderItemHot,
  thHeaderItemPressed,
  thHeaderItemLeftNormal,
  thHeaderItemLeftHot,
  thHeaderItemLeftPressed,
  thHeaderItemRightNormal,
  thHeaderItemRightHot,
  thHeaderItemRightPressed,
  thHeaderSortArrowSortedUp,
  thHeaderSortArrowSortedDown
);

enum TThemedHeader {
  thHeaderDontCare,
  thHeaderRoot,
  thHeaderItemNormal,
  thHeaderItemHot,
  thHeaderItemPressed,
  thHeaderItemLeftNormal,
  thHeaderItemLeftHot,
  thHeaderItemLeftPressed,
  thHeaderItemRightNormal,
  thHeaderItemRightHot,
  thHeaderItemRightPressed,
  thHeaderSortArrowSortedUp,
  thHeaderSortArrowSortedDown
};