GetFocus not working on other windows

[funkey]

Hello,

I tried to get the handle of the control with the focus from another window. I know I can do this with ControlGetFocus, but I just want to do it with the WinAPI. I can get the handle if I start the application with Run(), but if the application already exists I cannot get the handle. I googled a lot, but I didn't find the answer of the problem. Does anybody know how to do this?

#include <WinAPI.au3>

;~ Run("notepad.exe")
Global $hWnd = WinWait("[CLASS:Notepad]", "", 5)
If $hWnd = 0 Then Exit

Global $curThreadID = _Winapi_GetCurrentThreadId();
Global $iPID
Global $winThreadID = _Winapi_GetWindowThreadProcessId($hWnd, $iPID);
ConsoleWrite("PID notepad.exe: " & $iPID & @LF)
Global $success = _WinAPI_AttachThreadInput($curThreadID, $winThreadID, True);
ConsoleWrite("Success: attaching: " & $success & @LF)
Global $hCtrl = _Winapi_GetFocus();
$success = _WinAPI_AttachThreadInput($curThreadID, $winThreadID, False);
ConsoleWrite("Success: detaching: " & $success & @LF)
ConsoleWrite("Control handle with focus: " & $hCtrl & @LF)