How to use "GetWindowProc"?

[Roozbeh69]

Hi Everybody Does anybody know how to override the GetWindowProc method? I want to handle some specific messages in my own window procedure and direct the others to the base WndProc. Regards Roozbeh.

[Igor Vigdorchik]

1. You do not need to override GetWindowProc(), it can be done in the PreTranslateMessage() like so:

virtual BOOL CMyDlg::PreTranslateMessage(MSG* pMsg)
{
if (pMsg->message == WM_COMMAND)
OnCommand(true);

return FALSE;

}

2. If you still want to do it, here is an example how to override a GetDialogProc(), hope it's helpful:

DLGPROC CMyDlg::GetDialogProc()
{
return MyDialogProc;
}

// Our own dialog procedure that is mostly copied from
// CDialogImplBaseT<>::DialogProc() in Atlwin.h.
INT_PTR CALLBACK CMyDlg::MyDialogProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
CNoteDlg * pThis = (CNoteDlg*)hWnd;
// Set a ptr to this message and save the old value.
_ATL_MSG msg(pThis->m_hWnd, uMsg, wParam, lParam);
const _ATL_MSG* pOldMsg = pThis->m_pCurrentMsg;
pThis->m_pCurrentMsg = &msg;
// Pass to the message map to process.
LRESULT lRes;
BOOL bRet = pThis->ProcessWindowMessage(pThis->m_hWnd, uMsg, wParam,
lParam, lRes, 0);
// If window has been destroyed and this is the last message,
// then delete ourselves.
if (DEFERDELETE == pThis->m_bAutoDelete && pOldMsg == NULL)
{
delete pThis;
return FALSE;
}
// Restore saved value for the current message.
ATLASSERT(pThis->m_pCurrentMsg == &msg);
pThis->m_pCurrentMsg = pOldMsg;
// Set result if message was handled.
if(bRet)
{
switch (uMsg)
{
case WM_COMPAREITEM:
case WM_VKEYTOITEM:
case WM_CHARTOITEM:
case WM_INITDIALOG:
case WM_QUERYDRAGICON:
case WM_CTLCOLORMSGBOX:
case WM_CTLCOLOREDIT:
case WM_CTLCOLORLISTBOX:
case WM_CTLCOLORBTN:
case WM_CTLCOLORDLG:
case WM_CTLCOLORSCROLLBAR:
case WM_CTLCOLORSTATIC:
return lRes;
break;
}
::SetWindowLong(pThis->m_hWnd, DWL_MSGRESULT, lRes);
return TRUE;
}
if(uMsg == WM_NCDESTROY)
{
// Clear out window handle.
HWND hWnd = pThis->m_hWnd;
pThis->m_hWnd = NULL;
// Clean up after dialog box is destroyed.
pThis->OnFinalMessage(hWnd);
// If we want to automatically delete ourselves...
if (pThis->m_bAutoDelete)
{
// If no outstanding messages to process in call stack,
// m_pCurrentMsg will be NULL so we can delete ourselves.
if (pThis->m_pCurrentMsg == NULL)
delete pThis;
// Else set a flag so we can delete ourselves later.
else
pThis->m_bAutoDelete = DEFERDELETE;
}
}

return FALSE;

}

[Roozbeh69]

Thanks a lot for your help. Regards Roozbeh.