Eingebettetes Child window

#include <GUIConstants.au3>
#include <WindowsConstants.au3>
$hGUI = GUICreate("Test", 800, 600, -1, -1, BitOr($WS_MINIMIZEBOX, $WS_CAPTION, $WS_POPUP, $WS_SYSMENU, $WS_CLIPCHILDREN))
$PID	= Run("C:\Programme\SumatraPDF\SumatraPDF.exe -plugin "&$hGUI, "", @SW_HIDE)
$hWnd	= 0
$stPID	= DllStructCreate("int")
Do
	$WinList = WinList()
	For $i = 1 To $WinList[0][0]
    	If $WinList[$i][0] <> "" Then
        	DllCall("user32.dll", "int", "GetWindowThreadProcessId", "hwnd", $WinList[$i][1], "ptr", DllStructGetPtr($stPID))
        	If DllStructGetData($stPID, 1) = $PID Then
            	$hWnd = $WinList[$i][1]
            	ExitLoop
        	EndIf
    	EndIf
	Next
	Sleep(100)
Until $hWnd <> 0
$stPID = 0


If $hWnd <> 0 Then
	$nExStyle = DllCall("user32.dll", "int", "GetWindowLong", "hwnd", $hWnd, "int", -20)
	$nExStyle = $nExStyle[0]
	DllCall("user32.dll", "int", "SetWindowLong", "hwnd", $hWnd, "int", -20, "int", BitOr($nExStyle, $WS_EX_MDICHILD))
	DllCall("user32.dll", "int", "SetParent", "hwnd", $hWnd, "hwnd", $hGUI)
	WinSetState($hWnd, "", @SW_SHOW)
	WinMove($hWnd, "", 0, 0, 600, 400)
EndIf
GUISetState()
While 1
	$msg = GUIGetMsg()
	If $msg = -3 Then ExitLoop
WEnd