ensuring one instance of dialog box

[rishabhs]

dear all
i have an mfc dialog based app with frame as main window.
on app start an icon appears at the system tray and on dbl clicking that a dialog box appears. the problem is that on every dbl click, a new dialog box appears
how do i ensure that only one dialog appears at a time?

can anyone suggest something?

thanx

 

[williamu]

Hi,

In your app declare a pointer to the dialog box and in the apps constructor set it to 0. In your hander for the dblclick do a test to see if the pointer is 0, if it is 0 then you create an instance of the dialog. If the dialog does exists then show it, since it's only hidden when "parked" in the systray.

if (!m_pResults)
{
    // Dialog doen't exist so create it.
    m_pResults = new CSearchResults(m_pSearch, this) ;
    if (m_pResults)
	m_pResults->Create(CSearchResults::IDD, this) ; 
}
if (!m_pResults)
    AfxMessageBox("Unable to create Results Form!") ; 
else
{
    if (m_pResults->m_Connected)
    {
	if (!m_pResults->IsWindowVisible())
	{ m_pResults->ShowWindow(SW_SHOW) ; }
	m_pResults->StartSearch() ;
	m_pResults->SetFocus() ;
    }
    else
	SendMessage(UM_DESTROY_DIALOG, 0, IDD_SEARCH_RESULTS) ;
}

The code above works for me in that I create a single search results window. This window is then used to display results from a search done by the User. If the change the search pattern while the window is open all that happens is that the results displayed are changed.

HTH
--

William
Software Engineer
ICQ No. 56047340