Re: Closing modeless dialogs

From:
"Scott McPhillips [MVP]" <org-dot-mvps-at-scottmcp>
Newsgroups:
microsoft.public.vc.mfc
Date:
Wed, 12 Mar 2008 09:52:34 -0400
Message-ID:
<#ntOahEhIHA.4396@TK2MSFTNGP04.phx.gbl>
"Torsten Hensel" <Hensz@expires-31-03-2008.news-group.org> wrote in message
news:1205327375.84@user.newsoffice.de...

David Wilkinson wrote:

Maybe I'm missing something, but if you have an MFC dialog application
why don't you just use the default modal dialog? Why does your dialog
need to be modeless?


Because when I call DoModal the current thread waits for the dialog to be
closed.


No, the current thread executes a message pump, which is essential for
displaying the dialog.

But I want to display the dialog and continue directly with some
operations. This could be achieved with modal dialogs, but only when I use
a worker thread. The use of a modeless dialog is a simple (but not very
clean) alternative to a worker thread.


You can not "display the dialog and continue directly with some operations."
It's a contradiction in terms if you only have one thread. Displaying a
dialog requires that you process messages. If you are doing "some
operations" you are not processing messages. One thread can not do two
things at once.

(1) Use the default modal dialog. That's the only way to let your program
process messages for your dialog.

(2) In your dialog OnInitDialog call SetTimer, and add a message handler for
WM_TIMER.

(3) In each OnTimer call do a little bit of "some operations" and return.
THAT is a "simple (but not very clean) alternative to a worker thread."

--
Scott McPhillips [VC++ MVP]

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