Edit Question - KnowledgeHub

Title Body

I'm working on a class for my iPhone app, and I'd like it to register for and be aware of application state changes ( UIApplicationDidEnterBackgroundNotification , etc). Is there a way to register a class for notifications without having to keep an instantiated object in memory? I just want to have the appropriate notifications call the class to init, do some stuff, and then leave memory again. Right now I have the following in the init method: [[NSNotificationCenter defaultCenter] addObserver: self selector: @selector(handleEnteredBackground) name: UIApplicationDidEnterBackgroundNotification object: nil]; and this method elsewhere in the .m file of the class: - (void) handleEnteredBackground { NSLog(@"Entered Background"); } I instantiate the class once under applicationDidLoad , but since I don't do anything with it I presume ARC kills the object from memory and the app crashes (without any useful error codes, mind you) when I go to close it. If I switch handleEnteredBackground to a class method with a "+" sign, I get invalid selector errors when I close the app. The end goal is to instantiate a class once in the lifecycle of an app and have it be able to respond to app state changes without any additional code outside the class. Assume iOS 5 + Xcode 4.2+

Tags (comma-separated) Cancel