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Does prof-uis use special windows messages? We ran into trouble with WM_USER + 6 and I don’t know where the problem came from but if you have reserved messages I would like to know.

Thanks,
Seth

That’s backwards from what I meant. Something else seems to be intercepting the WM_USER+6 message that I send and crashes my application. It’s my fault for broadcasting the message but I don’t know what class is really messing up.

We would not recommend you using WM_USER messages because there is always a possibility that someone else is also using a message with the very same ID. So it it is possible to avoid using WM_USER, you could use the RegisterWindowMessage() function to retrieve a unique message ID.

I use SendMessageToDescendants() to reflect messages as appropriate to my application. When I reflected the message defined as WM_USER + 6, my slider control glitched and changed its number of tic marks and became unresponsive. When I redefined the message as WM_USER + 608, everything works fine. I tried to isolate the behavior and I think it is due to the broadcasting of WM_USER + 6 to all decendants but I don’t know why.

You can find out what is sending the unwanted (WM_USER+6) message simply by setting up breakpoints in message handlers for this message. The call stack window should show you where it is sent from.

We do not use (WM_USER+6) message in Prof-UIS. The WM_USER message is used in the resizable property sheet/page components only. Please let us know more about the problem.