iPhone 4 is there an absolutely certain way to have a long term NSTimer fire

Question

I keep having troubles with my NSTimers and background selectors. It is driving me nuts and takes a very long time to try out each tweak. To preserve my sanity, and the sani

Answer 1

One of the myriad issues with NSTimers is their run-loop dependency. Every thread has a single run loop. If you schedule a timer on a background thread, it will be scheduled on that thread's run loop. If that thread is short lived, which background threads often are, that timer will quietly die with it.

The solution is to guarantee the timer is run on a thread that will be alive when the timer fires. The best way to do these dedicated background timers in my experience is to not use NSTimer at all, and go for GCD timers instead. Better men than I have coded up GCD powered timers. I personally prefer Mike Ash's article and implementation, which comes with an explanation.