delphi - How to show the sort arrow on a TListView column?

Question

Windows Explorer has an arrow indicating which column a list view (in report view style) is sorted by and in which direction (ASC vs. DESC).

Is it possible to display such a sort indication arrow on a TListView in Delphi?

Answer 1

Here's some simple code to mark a header column as sorted ascending:

uses
  Winapi.CommCtrl;

var
  Header: HWND;
  Item: THDItem;
begin
  Header := ListView_GetHeader(ListView1.Handle);
  ZeroMemory(@Item, SizeOf(Item));
  Item.Mask := HDI_FORMAT;
  Header_GetItem(Header, 0, Item);
  Item.fmt := Item.fmt and not (HDF_SORTUP or HDF_SORTDOWN);//remove both flags
  Item.fmt := Item.fmt or HDF_SORTUP;//include the sort ascending flag
  Header_SetItem(Header, 0, Item);
end;

I have omitted error checking for the sake of simplicity. If you want the arrow in the opposite direction, I'm sure you can work out how to swap the logic around.

The key MSDN topic is that for the HDITEM struct.