Fire method when a specific nsdate has passed

Question

I want my App to call a method at an setter NSDate (It only needs to happen when the app is active, I'll handle passed events on launch in the app delegate).

I read about some ways to achieve such a behavior: On the one hand to work with performSelector:withObject:afterDelay: (But this doesn't look like a good way for me) or on the other hand to work with an NSTimer .

What is the best way regarding the app performance? One requirement is that you can cancel the event.

Answer 1

Using NSTimer is a simple solution. It has a property called fireDate that tells you when it's going to fire next. And it's a writeable property, so you can set that date to whatever you want.

Cancel the event by invalidating the timer object.