WM_TIMER remaining/elapsed time...
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From: Simon on 29 Apr 2010 05:29 Hi, I am fairly sure there isn't a straight forward way to do it but I thought I'd ask more knowledgeable people here first. let say I create a timer for 10 minutes. ::SetTimer( m_hWnd, TIMER_IDENT, 600000, NULL ); // WM_TIMER sent to CWnd queue Is it possible to 'pause' the timer or at know how many ms are left before the WM_TIMER event is fired? Many thanks Simon
From: Goran on 29 Apr 2010 06:31 On Apr 29, 11:29 am, Simon <b...(a)example.com> wrote: > Hi, > > I am fairly sure there isn't a straight forward way to do it but I > thought I'd ask more knowledgeable people here first. > > let say I create a timer for 10 minutes. > > ::SetTimer( m_hWnd, TIMER_IDENT, 600000, NULL ); // WM_TIMER sent to > CWnd queue > > Is it possible to 'pause' the timer or at know how many ms are left > before the WM_TIMER event is fired? Pause: no, you can only kill it and set it again. Remaining time: no way that I know of, so you will need to create a mechanic of your own. It's not hard (e.g. remember time of last WM_TIMER and then do long remaining = (lastTick+PERIOD)-Now()). What are you trying to achieve? (You did not ask a good question, because you did not say what you are trying to achieve; you said what you think you should do to achieve it. But normally, you get a better advice when you say what you are really trying to do; perhaps you won't even need any of this). Goran.
From: Hector Santos on 29 Apr 2010 07:30 Simon wrote: > Hi, > > I am fairly sure there isn't a straight forward way to do it but I > thought I'd ask more knowledgeable people here first. > > let say I create a timer for 10 minutes. > > ::SetTimer( m_hWnd, TIMER_IDENT, 600000, NULL ); // WM_TIMER sent to > CWnd queue > > Is it possible to 'pause' the timer or at know how many ms are left > before the WM_TIMER event is fired? > > Many thanks > > Simon No, but what you can do is have a 1 second or 1 minute timer and create a counter variables associated with the TIMER_IDENT. Maybe with a Start Button: void MyDialog::OnStartButtonClick() { m_TimerIdentCount = 10; // 10 mins countdown m_PauseButton = FALSE; SetTimer(TIMER_INDENT, 10000, NULL); // 1 min timer } then OnTimer has: void MyDialog::OnTimer(UINT nIdEvent) { if (nIdEvent == TIMER_INDENT) { if (!m_PauseButton) { m_TimerIdentCount--; // remove 1 minute if (m_TimerIdentCount <= 0) { RING_BUZZER() KillTimer(TIMER_INDENT); } } } } Something like that. -- HLS
From: Tom Serface on 29 Apr 2010 07:45 I would just create the time to tick off every second, then you could check variables like cancel, pause, and you'd always know how much time is left as it ticks down (you decrement a counter). If the routine is short you wouldn't see any real difference in your program speed. Another thing you could do is create a separate thread that keeps track of this sort of thing and just fires a message off to the appropriate window when the time comes. You could pause and restart and query that thread for state, etc. Tom "Simon" <bad(a)example.com> wrote in message news:e9LEA635KHA.1888(a)TK2MSFTNGP05.phx.gbl... > Hi, > > I am fairly sure there isn't a straight forward way to do it but I thought > I'd ask more knowledgeable people here first. > > let say I create a timer for 10 minutes. > > ::SetTimer( m_hWnd, TIMER_IDENT, 600000, NULL ); // WM_TIMER sent to CWnd > queue > > Is it possible to 'pause' the timer or at know how many ms are left before > the WM_TIMER event is fired? > > Many thanks > > Simon
From: Simon on 29 Apr 2010 07:55
> Pause: no, you can only kill it and set it again. > Remaining time: no way that I know of, so you will need to create a > mechanic of your own. It's not hard (e.g. remember time of last > WM_TIMER and then do long remaining = (lastTick+PERIOD)-Now()). I see what you are saying. I might do something like that. > > What are you trying to achieve? Yes, I am fairly sure I need it. We have some use cases to 'pause', (or delay), a timer. Here is a common example. We have a server application, when it starts, it checks online for new transactions every 10 minutes. During those 10 minutes the user can start a time consuming process, (printing of reports, connecting to another app, doing a backup), during the process we do not want to check for transactions. What I could do is: OnTimer() { if( busy_doing_something_important ) { // check again in 10 seconds } else { check_for_transactions() } } Or I could kill the timer and restart it again, but if the user print a new report every 9:59 minutes then there will be no checks for a very long time. On the other hand, if I check for transactions every time we complete a lengthy transaction then we might end-up checking too often, (during month end for example we print hundreds of reports). So on return of a lengthy operation I could check if the timer would have fired, and in that case check for transactions. Regards, Simon |