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Delay with process.messages

zulliger
zulliger asked
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Last Modified: 2008-02-01
I want to include a delay in my Delphi (3) program. I wan't to do this with a variable and a timer: I activate the timer,  and the the timer set this variable to true. during this time I ask if this variable is true, but the programm is busy only with this repeat routine. I want to use process.messages...... but I don't know how to include this in my programm. Can anyone make me a little exampleprogram???
Thank you!
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You need to write something like:
while ... do
  Application.ProcessMessages;

Commented:
It is like Ronit says, you've to include in your loop the Application.ProcessMessages.

But way don't you just use a delay function, instead of the timer?

Zif.

Commented:
Here are some delay procedures :

    How do you get your Delphi app to do nothing for a period of time?
    A:
    Uses
         ....
         Winprocs
         ....;

    Procedure delay(millisecs : longint);   { delay for given milliseconds }
    var
         endtime   : longint;
    begin
         endtime := gettickcount + millisecs;
         while endtime - gettickcount < 0 do
              Application.ProcessMessages;
         end; { delay }

    A:
    procedure Wait;
    var oldTime: LongInt;
    begin
      oldTime := GetCurrentTime;
      repeat
       { whatever}
      until GetCurrentTime - oldTime >= yourDelay;
    end;

    To which I would add:

    As current Windows does not have pre-emptive multi-tasking,
    it's normally good event-handling manners to allow Windows
    to jump in to the gap, so the { whatever } above should
    usually read:

              Application.ProcessMessages;


    A:
    Procedure Delay(DTime : LongInt);
    Var
      L : LongInt;
    Begin
      L := GetTickCount;
      While (Abs(L-GetTickCount) < DTime) do;
    End;

    The usage is "Delay(1000'th of a second)", for example
    Delay(5000) will wait 5 seconds.

Regards, Zif.

Commented:
have you noticed that this delay function kinda beets on the processor...was that why you have a timer?  so you can check it under a bigger cycle like every second look if you are still in the wait mode?...The RxLibraries have a neet little component called a RxClock that has an OnAlarm Event just set the AlarmHour, AlarmMinute, and AlarmSecond and it goes off at the second...with almost no system load I would say none but it does have to execute a few instructions a second... look around for RxLib 2.4 if you can't find it I can send it to you...the component is a visual clock thing but you could just snag out the code for defining the OnAlarm event to suit your needs.  take a look at
http://rx.demo.ru/
http://www.officeauto.com/res/rx/


Author

Commented:
Thank you for your answers!
Commented:
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