Question

I need to write some information to file before exiting application. How can I do that?

Answer 1

Supposing your app supports multitasking (and you’re on iOS 4 or above):

Override the applicationDidEnterBackground method in your app delegate, and do like the follwing:

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



bgTask = [ [UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:^{
    [app endBackgroundTask:bgTask];
    bgTask = UIBackgroundTaskInvalid;
}];

//do whatever writing you like    


if (bgTask != UIBackgroundTaskInvalid) {
    [[UIApplication sharedApplication] endBackgroundTask:bgTask];
    bgTask = UIBackgroundTaskInvalid;

}

}