U++ forum: Welcome to the forum

Search on this site

Search in forums

Home » U++ Library support » U++ Callbacks and Timers » How to properly set a timer

Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend

How to properly set a timer [message #49557]

Thu, 01 March 2018 10:19

koldo
Messages: 3453
Registered: August 2008

Senior Veteran

Hello all

This question is strangely derived from this post.

I wanted to ask you how to set properly a timer. Three options:

1. Inside a class derived from Ctrl
SetTimeCallback(time, THISBACK(callbackFunction));

2. In a GUI program, in a class not derived from Ctrl
¿?¿?¿?

3. In a console program
¿?¿?¿?

For the option 2, I have used historically ::SetTimeCallback(time, THISBACK(callbackFunction));
However, for unknown reasons, it may sometimes crash the program.

Best regards
Iñaki

Report message to a moderator

Re: How to properly set a timer [message #49558 is a reply to message #49557]

Thu, 01 March 2018 10:47

Oblivion
Messages: 1241
Registered: August 2007

Senior Contributor

Hello Koldo,

Have you tried TimeCallback class? AFAIK it doesn't -directly- need a Ctrl (But it calls Upp::SetTimeCallback() too. Still, It may affect the behaviour -crash- differently ).

On console I haven't used it. But you can use a) a thread, or b) waitForSingleObject on Windows, and timer functions on posix. (Or you can emulate timer using sigtimedwait, creating a custom signal, or even using select call with a socket.)

Best regards,
Oblivion

Github page: https://github.com/ismail-yilmaz
Bobcat the terminal emulator: https://github.com/ismail-yilmaz/Bobcat

[Updated on: Thu, 01 March 2018 11:13]

Report message to a moderator

Re: How to properly set a timer [message #49559 is a reply to message #49557]

Thu, 01 March 2018 15:12

mirek
Messages: 14271
Registered: November 2005

Ultimate Member

koldo wrote on Thu, 01 March 2018 10:19

Hello all

This question is strangely derived from this post.

I wanted to ask you how to set properly a timer. Three options:

Generally, you have to avoid situation where callback is invoked after target instance is destroyed.

Quote:

1. Inside a class derived from Ctrl
SetTimeCallback(time, THISBACK(callbackFunction));

In client code, use TimerCallback. TimerCallback destructor removes the callback from the timer queue if necessarry.

You can use SetTimeCallback directly, but then you have to rember id and remove in destructor.

Quote: