Welche unit wird benötigt?

[bitsetter]

Versuche es mal so:

Delphi-Quellcode:

const
  BtnIndex= 2;
var
  TB: commctrl.TBBUTTONINFO;
begin
  ZeroMemory(@TB, SizeOf(TB));
  TB.cbSize := sizeof(TB);
  TB.dwMask := commctrl.TBIF_COMMAND;
  SendMessage(..., TB_GETBUTTONINFO, BtnIndex, Cardinal(@TB));
  SendMessage(..., TB_PRESSBUTTON, TB.idCommand, MAKELONG (1, 0));