[RESOLVED] EnumChildWindows & FindWindow doesn't work MFC but works Console

[eclessiastes]

Hello
I'm trying to get the message from a static text in another application. I have this code which works perfectly in console application:

BOOL CALLBACK EnumChildProc2(HWND hwnd, LPARAM lParam) {
	counter2++;
	if (counter2 == 6) // counter 6 is the static text child
	{

		cout << "hwnd_Child 6 = " << hwnd << endl;
		HWND hand = (HWND)hwnd;

		char szBuf[2048];
		LONG lResult;
		lResult = SendMessage(hwnd, WM_GETTEXT, sizeof(szBuf) / sizeof(szBuf[0]), (LPARAM)szBuf);
		printf("%s", szBuf); // it prints the message correctly
	}
	return TRUE; 
}

int main() {
EnumChildWindows(FindWindow("#32770", "Unable to Write"), EnumChildProc2, 0);
}

It works very well in console application but it seems that bool callback function doesn't work as i need in MFC application . This is the code i used in MFC:

BOOL CALLBACK EnumChildProc2(HWND hwnd, LPARAM lParam) {
	counter_Child6++;
	if (counter_Child6 == 6)
	{
		HWND hand = (HWND)hwnd;
		
		char szBuf[2048];
		LONG lResult;
		lResult = SendMessage(hwnd, WM_GETTEXT, sizeof(szBuf) / sizeof(szBuf[0]), (LPARAM)szBuf);
		CString ssString;
		ssString.Format(_T("%s"), szBuf);
		AfxMessageBox(ssString);
	}
	return TRUE; 
}

CWnd *pWnd = FindWindow(_T("#32770"), _T("Unable to Write"));
	if (NULL != pWnd)
	{
		listControl1.InsertItem(0, _T("Window Exists"));
		EnumChildWindows((HWND)pWnd, EnumChildProc2, 0); //this function doesn't afxmessagebox anything
	}
	else
	{
		listControl1.InsertItem(0, _T("Does not Exists"));
	}

Any help would be greatly appreciated! Thanks

[2kaud]

CWnd *pWnd = FindWindow(_T("#32770"), _T("Unable to Write"));

FindWindow() returns type HWND, not CWnd*

If you want to use the mfc FindWindow() which does return a CWnd*, then you need

CWnd *pWnd = CWnd::FindWindow(_T("#32770"), _T("Unable to Write"));

[VladimirF]

FindWindow() returns type HWND, not CWnd*

If you want to use the mfc FindWindow() which does return a CWnd*, then you need

CWnd *pWnd = CWnd::FindWindow(_T("#32770"), _T("Unable to Write"));

...unless you call it from the class that is derived from CWnd. In that case, you would need to specify global scope to get the HWND version:

HWND hWnd = ::FindWindow(_T("#32770"), _T("Unable to Write"));

[VladimirF]

BOOL CALLBACK EnumChildProc2(HWND hwnd, LPARAM lParam) {
	counter_Child6++;

Any help would be greatly appreciated! Thanks

What is counter_Child6++? Where is it defined? How is it initialized?
Did you debug your EnumChildProc2() function? Is it called? How many times? Looks like counter_Child6 is never equal to 6...
Also, you shouldn't rely on the sequential index of the static control; what if the order changes or another control is inserted?
Besides, you don't need to enumerate windows if you are not checking any of their properties.
Check out GetWindow function.

[eclessiastes]

...unless you call it from the class that is derived from CWnd. In that case, you would need to specify global scope to get the HWND version:

HWND hWnd = ::FindWindow(_T("#32770"), _T("Unable to Write"));

I changed

CWnd *pWnd = CWnd::FindWindow(_T("#32770"), _T("Unable to Write"));

with

HWND hWnd = ::FindWindow(_T("#32770"), _T("Unable to Write"));

now it works perfectly! I've been up 2 days for this
Thank you Vladimir

[eclessiastes]

One last question: I'm trying to change static text from bool callback function but i get error: "Encountered an improper argument"

CMFCApplication1Dlg* dlsg;
dlsg->status.SetWindowTextW(L"Status: Working..");

Any idea how to access main dialog controls from bool callback ? Thank you

[OReubens]

only a handfull of messages support sending data between programs like this.
SetWIndowText internally calls SendWindow with as parameter the pointer to your string data.
that pointer value is entirely meaningless in the other application.

THe work around is somewhat involving...
allocate memory in the other process (VirtualAllocEx)
copy the string contents into that memory in the other process (WriteProcessMemory)
SendMessage with the v-pointer of that other process
clean up the allocated memory. (VirtualFreeEx)