Creating timer to count seconds and tenths of seconds

[BrightMedia]

Hello,

Does anyone know how to create a timer that counts seconds and tenths of seconds in the format hours:minuts:seconds:tenths of seconds?

[mariano_donati]

To start off, you should create a timer which fires every 0.1 sec. Then a variable elapsedTime should get incremented by 0.1 whenever the timer ticks. Then:

hours = elapsedTime / 3600;
minutes = (elapsedTime / 60) % 60;
seconds = elapsedTime % 60
tenths of seconds = elapsedTime - floorf(elapsedTime);

[Domele]

Sorry marianio but that's not the correct approach. You should use NSDate's timeIntervalSinceDate method. When you start your timer, set an ivar named startDate. In the timer method, call timeIntervalSinceDate passing in startDate on the current date. Then, assuming mariano's way of calculating the variables are correct, use his code on the returned NSTimeInterval.

[mariano_donati]

Domele: thanks for pointing that out, I agree, that is the correct approach.

[BrightMedia]

Originally Posted by Domele

Sorry marianio but that's not the correct approach. You should use NSDate's timeIntervalSinceDate method. When you start your timer, set an ivar named startDate. In the timer method, call timeIntervalSinceDate passing in startDate on the current date. Then, assuming mariano's way of calculating the variables are correct, use his code on the returned NSTimeInterval.

Thanks a lot everybody!