Killing child and parent windows

[inquilaab]

Hi.

I have a program that creates child windows (not dialogs)

When the child window is closed (clicking on the X), ~method is called, which deletes allocated storage and sends a message to the parent window telling that the window was closed.

Now in a situation, where the child window is up and the parent window is up, and we close the parent window, as much as I understand MFC, the parent window is killed before the child window is. So when the ~method of the child window is called, it sends a message to the parent window, but the parent window has already been (deleted? destroyed?) so the program just exits at that point. How can I avoid this or work around this or fix this?

Thank you.

[Apoch]

As far as I know MFC ensures that child windows unload before the parent, unless you are doing something "creative" like adding the child window at run time... or am I mistaken about that?

[inquilaab]

My source was "Programming Windows with MFC second Edition" by Jeff Prosise.

Chapter 12, page 721, says:

"Child windows, on the other hand, are destroyed after their parents are destroyed."

What he is talking about is toolbars, but the concept should still apply.

[Apoch]

According to MSDN, calling DestroyWindow() will destroy all children first, then the parent window.

[inquilaab]

So that would mean, when the parent window is killed, and it tries to destroy the child window, and a child window sends a message to the parent window, that should be accepted?

[Apoch]

Yes, it should be. If memory serves, I've actually done that before Just don't count on the parent window hanging around long enough to receive and process the message unless you return 0 from your child window's DestroyWindow() proc.