applicationWillTerminate works as long as I don't switch off the iPhone...

Question

Hi,

to save some variables of my apps I use:

-(void)applicationWillTerminate:(UIApplication *)application {

NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
[prefs setFloat: self.viewController.sLabel.contentOffset.y forKey:@"floatKey"]; 
[prefs setObject:self.viewController.newText forKey:@"stringVal"];
[prefs synchronize];

}

and to retrieve them, via a button, I do the following:

-(IBAction) riprendi:(id) sender {

NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults]; 
float myFloat = [prefs floatForKey:@"floatKey"];

//some actions here

}

Everything is working on the simulator. However, using it on a real iPhone, the variables' saving and retrieving works just if you press the Home button, exiting the app and opening again but NOT if you switch off/on the iPhone. In this case, the variables get simply lost once you re-open the app...

What am I missing?? This is actually driving me crazy :(

Thank you so much ;) Fabio

Answer 1

If you mean hitting the lock button on the top of the phone by saying "switching on/off", then it won't work, because locking the phone does not cause an application to quit. Your applicationWillTerminate: method is only called when you exit you're application to the home screen or to some other application. When the user presses the Sleep button, applicationWillResignActive: will be send to your application-delegate.

Apple's iPhone OS Programming Guide has a section on handling interruptions.