Win32 - Contents in tab control disappearing when dragged off screen

I am using resources with Win32 to create a dialog containing a single tab control. The tab works fine when changing tabs but somehow dragging the window off screen ( eg. dragging it past bottom of screen then back up ) will cause the tab contents开发者_如何转开发 to disappear. I think it may be a problem with how I've set the clipping properties but after much fiddling I still didn't get it working exactly how I expect.

I have uploaded a basic skeleton project here which has the bare minimum required to reproduce this problem and would be very grateful if someone could check it out.

http://localhostr.com/file/nPTbTTQ/skeleton.rar

It is a Z-order problem, the dialog is behind the tab control. Change the parent of the inner dialog from hwndDlg to hwndTab. I don't want to guess why you saw the static control text at all.