Question

I would like to save some data from an array into a plist file when the applicationDidEnterBackground is called. I’m trying to figure it out how to access my array from the applicationDidEnterBackground method. Is there any best practice to do this?
Many thanks
Marcos

Answer 1

Put the code in the class that actually has the data. Have the class register for the UIApplicationDidEnterBackgroundNotification notification.

// Put this in the `init` method
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(backgrounding) name:UIApplicationDidEnterBackgroundNotification object:nil];

// The method that gets called
- (void)backgrounding {
    // save the data
}

// Put this in the `dealloc` method
[[NSNotificationCenter defaultCenter] removeObserver:self name:UIApplicationDidEnterBackgroundNotification object:nil];

With this setup you don’t have to get anything into the UIApplicationDelegate and the responsibility is kept where it belongs.