AfxMessageBox remains on screen

I am working on a Dialog based MFC App on WinCE 4.20

When I start a lengthy processing task (triggered by a button press) I show
a messagebox (AfxMessageBox) that asks the user for confirmation. Once
confirmation has been received I start processing, but the message box
doesn't disappear until I finish my processing and exit my message handler.

Can I call some sort of idle processing to make the message box get cleared?
I would like to implement a modeless progress dialog to show that I am
working. Will it have the same update problem as the message box is showing
now?

TIA
Steve McKewen


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