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AfxMessgeBox "eats" thread messages

I have a CWinThread derived class that implements a thread with a message queue.  Other threads post thread messages (hWnd = NULL) to this thread using PostThreadMessage().  Normally everything works fine, but if this thread displays a message box, any thread messages that are posted to it while the message box is displayed, are lost.  Is this the way things should work?  Is there a way not to lose the messages posted while the message box is displayed?
1 Solution
Tommy HuiEngineerCommented:
Yes, because it uses its own internal message loop to display the message box. Normally, you do not want to have a worker thread displaying UI objects. If you need this capability, the better thing to do is to not use anything that can bring up its own message loop (i.e. MessageBox or AfxMessageBox). Instead, use a modeless dialog, and if you're using Visual C++ 5.x, then you can also use modal dialogs.

boreillyAuthor Commented:
I would like to give a grade of excellent, but the wording of the answer is not perfectly clear to me.  When you say "Yes, because it uses its own internal message loop", does "it" refer to MessageBox()?  Are you saying that the messagebox functions implement their own message loops? Do they intercept all messages to the thread?

Thank you very much.
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