Re: MessageBox hangs app. AfxMessageBox

From:

"Scott McPhillips [MVP]" <org-dot-mvps-at-scottmcp>

Newsgroups:

microsoft.public.vc.mfc

Date:

Fri, 9 Nov 2007 19:34:16 -0500

Message-ID:

<ubOV1FzIIHA.484@TK2MSFTNGP06.phx.gbl>

"JC" <elvis_is_king@bellsouth.net> wrote in message
news:Xns99E39E763A152elvisiskingbellsouth@216.77.188.18...

BOOL CTestCaseDlg::OnInitDialog()
{
   CDialog::OnInitDialog(); // wizard generated

   ... Other wizard generated code...

   m_pPSheetCase = new CPSheetCase(m_sWinTitle, (CWnd*)this, 0);
   m_pPSheetCase->Create((CWnd*)this, dwStyle);
   m_pPSheetCase->ShowWindow(SW_SHOWNORMAL);
   m_pPSheetCase->SetFocus();

   m_pbIDOK = (CButton*)GetDlgItem(IDOK);
   m_pbIDOK->EnableWindow(0);
   m_pbIDOK->ShowWindow(0);

I don't know the source of your MessageBox hang, but I notice that you save
the results of GetDlgItem in several member variables. Don't do that!
GetDlgItem returns a temporary pointer that MFC will delete some time after
the calling function returns. Using the pointer beyond the scope of one
function is certain to cause an access violation at some point.

If you want member variables that refer to controls then right-click on the
control in your resource and select 'Add Variable.' This actually gives you
much prettier code than using GetDlgItem, and it is safer too.

--
Scott McPhillips [VC++ MVP]