Re: Multiple modal windows with the same parent
"marekdec" <marekdec@gmail.com> wrote in message
news:76cb00ca-9d79-4569-9234-1bf475684f62@s37g2000prg.googlegroups.com...
On Jan 29, 4:19 pm, "Mark Salsbery [MVP]"
<MarkSalsbery[MVP]@newsgroup.nospam> wrote:
"marekdec" <marek...@gmail.com> wrote in message
news:6bbc58d3-4d46-4526-a380-231fc8f80f41@d70g2000hsb.googlegroups.com...
On Jan 28, 12:41 pm, "Mark Salsbery [MVP]"
<MarkSalsbery[MVP]@newsgroup.nospam> wrote:
If you put a breakpoint on the DestroyWindow() call in
CDialog::DoModal(),
does execution stop there for every dialog closed?
Also, are all these dialogs created on the same thread?
Mark
--
Mark Salsbery
Microsoft MVP - Visual C++
I am using VS 2003 and MFC 7.1. My project uses modal dialogs
excessively.
DestroyWindow() is not being called. It seems like ModalLoop could not
be finished. Though EndModalLoop is invoked and WM_NULL message is
sent. And what is weird another button handler calls EndDialog in the
same way and this time it succeeds.
It works perfectly when I call winapi EndDialog.
I can't imagine why, since that's the wrong API to close a modeless
dialog,
as pointed out by Nish in his article.
According to both Nish's description and MSDN this API call is wrong,
though it appears somebody put it there for a reason (now I believe it
wasn't just a simple mistake). I'm just trying to say that I ran into
circumstances when Nish's fix doesn't work.However it worked for most
of my dialogs, it turned out that one of them just stopped closing (in
certain circumstances which don't seem to be special).
It also looks like there is something in API EndDialog function which
breaks the modal loop it it hasn't been broken by EndModalLoop() -
this is only my assumption.
These dialogs are all created on the same thread, right?
If so, then having two modal dialogs with the same parent shouldn't be an
issue for MFC design since only a modal dialog can spawn another modal
dialog, in which case the second dialog's parent would be the first
dialog
window. In that case, the MFC code should work fine.
But isn't it possible the first modal window creates another modal
window with another parent?
My case is both of them have AfxGetMainWnd() as parent.
Sure, it's possible. But it's not necessarily right. Conceptually, and
using the definition of "modal", it makes no sense to have two modal dialogs
with the same parent. This is just my opinion, of course, and it's been
argued here before. I'm just saying, the way the MFC code was written
(right or wrong) seems to agree.
Also...is this only an issue when closing the dialogs in the same order
they
were created??
No, the dialogs are closed in reverse order i.e. the last is the first
to be closed.
Interesting....looking at the code (MFC 9) I would expect it to work unless
the first dialog is closed first...
Regardless, if it was me, I would override DoModal() and implement it the
way I need it. It wouldn't be the first time I've wanted different behavior
than MFC's implementation :)
Mark
--
Mark Salsbery
Microsoft MVP - Visual C++
Thanks,
Marek