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Re: TWAIN Event Loop

Forums › TWAIN Classic › TWAIN/WIA › Re: TWAIN Event Loop

June 14, 2005 at 7:30 pm #23097
JonHarju
Participant
  • Topics - 0
  • Replies - 13
  • Total Posts - 13

Hello,

It’s not clear what you mean by buttons not working, this could be a variety of things. A few of them are event loop related as you have surmised…

Remember to forward all messages using DAT_EVENT/MSG_PROCESSEVENT and inspect the return code. If the return code is TWRC_DSEVENT then you have to inspect the TWMessage component of the structure – if this is MSG_XFERREADY or MSG_CLOSEDSREQ then you are expected to do something. It is possible that TWMessage will not be either of these in which case you are just supposed to ignore it and continue on to the next message in the queue.

If the return code is TWRC_NOTDSEVENT then you are expected to allow windows to process the message normally with TranslateMessage, DispatchMessage calls.

Remember – if you recieve TWRC_DSEVENT – you are not to dispatch the message to TranslateMessage, DispatchMessage at all – this will cause all kids of strange GUI behavior if you do.

Best Regards,
Jon Harju

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