EXC_BAD_ACCESS by resetting NSTimer

Question

I want to reset two NSTimers with a new TimeInterval. It would be no problem if I know if they arent released before reseting them.

I can't work like this:

[timer invalidate];

if(startTimers == YES)
   timer = [NSTimer scheduledTimerWithTimerInterval:...]

because I don't know if the timer was invalidated before I invalidate it.

And if I invalidate a released timer (on invalidation a timer gets released) I get a EXC_BAD_ACCESS.

Answer 1

When you release the timer, also set its variable to nil. Then [timer invalidate] will silently do nothing if timer is nil.

[timer invalidate];
timer = nil;