Re: Intermittent work in UI thread

"Scott McPhillips [MVP]" <org-dot-mvps-at-scottmcp>
Mon, 15 Oct 2007 15:06:43 -0400
"Pedro Ferreira" <> wrote in message


I'm trying to create a UI thread to do constant background work, but I'm
having some design problems.

The thread needs to fetch records from a database. do some processing on
each record and, when there are no more records, sleep for 1 minute before
check the database again. The process will be controlled with thread
messages (to start, pause, query...).

My problem is where should I put the processing work. I need it to be
responsive between cycles, where the process waits for 1 minute, so I can
stop it in that period. My only idea is using OnIdle to do the work. But
then, how should I make it real idle when waiting for 1 minute?

Could anyone give some hints on what is the way to go?


Pedro Ferreira

You can't use Sleep and still be responsive to messages. Instead of using
Sleep you could use SetTimer in the main thread and post a message to the
thread, or SetTimer to a hidden window within the thread, or you could use a
loop within the thread and use MsgWaitForMultipleObjects within the loop.
MsgWaitForMultipleObjects has a timeout parameter that gives you the sleep
period, but it also returns early if a message or event comes along.

Scott McPhillips [VC++ MVP]

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