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How to handle WM_KEYDOWN in a Dialog???

Hello,
I have a problem.

I'm writing a standard application
on Visual C++, using Win32 and
the ATL classes included in
the headers ATLBase.h and ATLWin.h.
I use my own classes derived from:

CMyWindow : public CWindowImpl<CMyWindow>

CMyDialog : public CDialogImpl<CMyDialog>

I make my main window,
and then open a dialog at some time.

My question is:
How to handle for example the WM_KEYDOWN message in this
dialog.
I want when I press for example "Alt+A" and the focus
is in any of the controls in the dialog, this WM_KEYDOWN message to be handled from a single function
for example:
CMyDialog::OnKeyDown(.........),
not from this control's WM_KEYDOWN handler.

If this would help, I want to make the same as the Form KeyPreview property in Visual Basic does.
The WM_KEYDOWN should be handled somehow firstly by the dialog, and
then by the concreate control.

How could I do this???

Thank you in advance.

Pavel Tsekov, Varna, Bulgaria

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mblat

There is an article Q117563 in Microsoft Knowleage Base.
HOWTO: How to Trap WM_KEYDOWN Messages in a CDialog.

It shows the way for MFC based app. I see that you are using WTL, but it may point you to the right direction.

Hope it helps.

Vinayak Kumbar

Hi,

I am not sure about the architecture of ur app. If u r using MFC, then using classwizard, map the PreTranslateMessage(...) function to ur dialong class and modify it as

BOOL CTestDlg::PreTranslateMessage(MSG* pMsg)
{
if(pMsg->message == WM_KEYDOWN)
{
//Here U R when a key is hit, but, Alt is handled differently.
//So u can get here by hitting any other key combinations. Like
//if(pMsg->wParam == 'B')
// Key B is hit
//and
//if(GetKeyState(VK_CONTROL) & 0x8000) && (pMsg->wParam == 'A'))
// Key Ctrl+B is hit
}

//When Alt is hit check like this
if((GetKeyState(VK_MENU) & 0x8000) && (pMsg->wParam == 'A'))
{
// U R Here as User hit Alt+A
//Call Ur Function!!!!
DoKeyProcess();
}

return CDialog::PreTranslateMessage(pMsg);
}

void CTestDlg::DoKeyProcess()
{
AfxMessageBox("Alt+A Hit");
}

Here DoKeyProcess()is declared as void DoKeyProcess()in public section of dialog's .h file

Try it out.
VinExpert

Moondancer

Please finalize the following year 2001 question:
https://www.experts-exchange.com/jsp/qShow.jsp?ta=visualbasic&qid=20246850
Moondancer - EE Moderator

SrinivasaRao

i think vinexpert is right:)
bsr

paul_tsekov

ASKER

No, the EXPERT is not right.
I'm using the CDialogImpl<> class,
not CDialog.
I'm not talking about MFC here.
I talk about ATL!!!!!!!!!!!!!!!!

paul_tsekov

ASKER

No, the EXPERT is not right.
I'm using the CDialogImpl<> class,
not CDialog.
I'm not talking about MFC here.
I talk about ATL!!!!!!!!!!!!!!!!