Child window handle not known

mvanrijnbach · 03-10-2010, 03:06 AM

I defined a child window in my Window procedure as follows:

Code:

for(i = 3; i < 13; i++) hwndEdit[i] = CreateWindowEx(WS_EX_CLIENTEDGE, TEXT("edit"), TEXT(""), WS_CHILD | WS_VISIBLE | WS_BORDER | ES_LEFT | ES_AUTOHSCROLL, 2*cxChar, (6+(2+7/4)*i)*cyChar, 10*cxChar, 7*cyChar/4, hwnd, (HMENU) i+3, ((LPCREATESTRUCT) lParam) -> hInstance, NULL);

For i=5 I obviously have a child window ID of 8. In the procedure I can communicate with this child window through this ID. However, if I try to communicate with this child window in a Dialog procedure it doesn't work. If I try to get the child window handle with:

Code:

hChild = GetDlgItem(hwnd, 8);
if(hChild) MessageBox(NULL, TEXT("A handle is returned"), TEXT("Warning!"), MB_OK | MB_ICONINFORMATION);

the MessageBox will not show up. hwnd is provided as a parameter to the Dialog Procedure. What am I doing wrong?

mvanrijnbach · 03-10-2010, 03:42 AM

Actually I think I should use hChild = GetDlgItem(GetParent(hwnd), 8), because hwnd is the handle to the Dialog Window. The child window with ID 8 also has the parent of the Dialog Window as its parent.

mvanrijnbach · 03-10-2010, 03:43 AM

hmmm, still this doesn't work though....

mvanrijnbach · 03-10-2010, 06:31 AM

ok, this is pretty stupid. I fixed it myself

The 'i+3' after (HMENU) in CreateWindow has to be in between brackets, otherwise only the handle to ID equal to 3 is known.

03-10-2010, 03:06 AM	#1
mvanrijnbach Registered User Join Date: Feb 2010 Posts: 34	Child window handle not known I defined a child window in my Window procedure as follows: Code: for(i = 3; i < 13; i++) hwndEdit[i] = CreateWindowEx(WS_EX_CLIENTEDGE, TEXT("edit"), TEXT(""), WS_CHILD \| WS_VISIBLE \| WS_BORDER \| ES_LEFT \| ES_AUTOHSCROLL, 2cxChar, (6+(2+7/4)i)cyChar, 10cxChar, 7*cyChar/4, hwnd, (HMENU) i+3, ((LPCREATESTRUCT) lParam) -> hInstance, NULL); For i=5 I obviously have a child window ID of 8. In the procedure I can communicate with this child window through this ID. However, if I try to communicate with this child window in a Dialog procedure it doesn't work. If I try to get the child window handle with: Code: hChild = GetDlgItem(hwnd, 8); if(hChild) MessageBox(NULL, TEXT("A handle is returned"), TEXT("Warning!"), MB_OK \| MB_ICONINFORMATION); the MessageBox will not show up. hwnd is provided as a parameter to the Dialog Procedure. What am I doing wrong?
mvanrijnbach is offline

03-10-2010, 03:42 AM	#2
mvanrijnbach Registered User Join Date: Feb 2010 Posts: 34	Actually I think I should use hChild = GetDlgItem(GetParent(hwnd), 8), because hwnd is the handle to the Dialog Window. The child window with ID 8 also has the parent of the Dialog Window as its parent.
mvanrijnbach is offline

03-10-2010, 03:43 AM	#3
mvanrijnbach Registered User Join Date: Feb 2010 Posts: 34	hmmm, still this doesn't work though....
mvanrijnbach is offline

03-10-2010, 06:31 AM	#4
mvanrijnbach Registered User Join Date: Feb 2010 Posts: 34	ok, this is pretty stupid. I fixed it myself The 'i+3' after (HMENU) in CreateWindow has to be in between brackets, otherwise only the handle to ID equal to 3 is known.
mvanrijnbach is offline

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