Two dialogs in one MFC application - winapi

Question

I am trying to make a dialog based MFC application , where two dialogs needs to be shown sequentially.
What that means is , once the first dialog(modal) is shown and dismissed (by pressing OK), the second dialog needs to be brought up.My requirement is the second dialog should be modeless.
But what I observe is the second dialog is shown but none of the message handling function are being called in response of user messages.I think the message map itself is not working, while the overridden functions(like OnInitdialog) are being called. I tried replacing this modeless dialog with a modal one , and alas, the doModal() itself fails.
Here is the little code:
CFirstDlg dlg;
m_pMainWnd = &dlg;
INT_PTR nResponse = dlg.DoModal();
if (nResponse == IDOK)
{
// TODO: Place code here to handle when the dialog is
// dismissed with OK
// TODO: Place code here to handle when the dialog is
// dismissed with Cancel
CSecondDlg *dlgModeLess = new CSecondDlg();
dlgModeLess->Create(CSecondDlg::IDD,NULL);
m_pMainWnd = dlgModeLess;
dlgModeLess->ShowWindow(SW_SHOW);
dlgModeLess->UpdateWindow();
}
Here is the message map of the second dialog:
BEGIN_MESSAGE_MAP(CSecondDlg, CDialog)
ON_MESSAGE(TRAY_MESSAGE,OnTrayMessage)
ON_BN_CLICKED(IDOK, &CSecongDlg::OnBnClickedOk)
ON_BN_CLICKED(IDC_RADIO1, &CSecondDlg::OnBnClickedRadio1)
END_MESSAGE_MAP()
I think I am doing something conceptually wrong. Kindly share your thoughts on what need to be done to tackle such a scenario.

Answer 1

As I mentioned in a previous post, it is not necessary that the second dialog be non modal.
Just do something like this:
BOOL CMyTestApp::InitInstance()
{
CMyTestDlg dlg;
m_pMainWnd = &dlg;
int nResponse = dlg.DoModal();
if (nResponse == IDOK)
{
COtherDlg Dlg ;
m_pMainWnd = &dlg;
if (Dlg.DoModal() == IDCANCEL)
{
...
}
}
else if (nResponse == IDCANCEL)
{
...
}
return FALSE;
}

Answer 2

When you create a modeless dialog box, control will return to your calling function right away, so you need to declare variable dlgModeLess at a global scope and make sure your program/scope is still active until the dialog box finishes

Answer 3

I have solved this problem and this turned out to be interesting.
It seems that Cdialog::Create() itself is not sufficient for creating a fully operative modeless dialog box. We have to supply a win32 style message loop to it.
So this effectively makes two message loops in the program, one provide my MFC framework and the one that I wrote after returning from IDOK. Here is the modified code.
CSecondDlg *dlgModeLess = new CSecondDlg();
dlgModeLess->Create(CSecondDlg::IDD,NULL);
CTrayIconDlg dlg;
m_pMainWnd = &dlg;
INT_PTR nResponse = dlg.DoModal();
if (nResponse == IDOK)
{
// TODO: Place code here to handle when the dialog is
// dismissed with OK
// TODO: Place code here to handle when the dialog is
// dismissed with Cancel
MSG leftmsg;
PeekMessage(&leftmsg,m_pMainWnd->m_hWnd,0,0,PM_REMOVE);
MSG msg;
BOOL bRet;
while ((bRet = GetMessage(&msg, dlgModeLess->m_hWnd, 0, 0)) != 0)
{
if (bRet == -1)
{
// Handle the error and possibly exit
}
else if (!IsWindow(hWnd) || !IsDialogMessage(hWnd, &msg))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
}
}
This code works as expected, The interesting thing to note here is the PeekMessage function which removes a WM_QUIT message that is inserted in the thread's message queue once the first dialog is dismissed as we do not want to quite at that point of time. This i believe is done by the MFC framework.