Re: ? Extending and (Forcibly?) Overriding a Class

From:

"Doug Harrison [MVP]" <dsh@mvps.org>

Newsgroups:

microsoft.public.vc.mfc

Date:

Tue, 02 Dec 2008 15:55:52 -0600

Message-ID:

<qqabj4l8uoarbfkagsfaje2ti80mdcfvrh@4ax.com>

On Tue, 2 Dec 2008 16:35:20 -0500, "Alec S." <nospam@127.0.0.1> wrote:

That makes sense; I actually came to the same conclusion when I tried to analyze
exactly what occurs when an item is inserted. I?m just not sure how or where to
handle that message. Looking at the properties pane of the class, there are a
few places I could conceivably handle it: WindowProc, PreTranslateMessage, etc.
(there?s no entry in the handler list for LVM_? like there is for LVN_?). Which
one is appropriate for this?

If there is no ClassWizard help, use ON_MESSAGE. See the last paragraph in
this recent message for reasons why WindowProc would not be the place:

http://groups.google.com/group/microsoft.public.vc.mfc/msg/52e6244c17827614?hl=en

See my other messages in that thread for more on message map subtleties. As
for PreTranslateMessage, only queued (posted) messages go through it, so
that wouldn't be the place to do it either.

While I?m handling things, any idea how I can trap the Ctrl-+ key that causes
list controls to auto-resize the columns? I can use use an OnKeyDown handler to
check for that key combination and prevent it altogether, but I don?t want to do
that. I am trying to find the handler that does the resizing so that I can
resize only columns that are not set to no-resize, but I can?t find it.

I'm not familiar with that feature. If you can't find a Windows message for
it, WM_KEYDOWN is probably where to do it. I don't know where you would
find the handler for the message except in the Windows source code. :)

--
Doug Harrison
Visual C++ MVP