Proper way to exit iPhone application?

Question

I am programming an iPhone app, and I need to force it to exit due to certain user actions. After cleaning up memory the app allocated, what\'s the appropriate method to ca

Answer 1

You should not directly call the function exit(0) as it will quit the application immediately and will look like your app is crashed. So better to show users a confirmation alert and let them do this themselves.

Swift 4.2

func askForQuit(_ completion:@escaping (_ canQuit: Bool) -> Void) {
    let alert = UIAlertController(title: "Confirmation!", message: "Do you want to quit the application", preferredStyle: .alert)
    alert.addAction(UIAlertAction(title: "Yes", style: UIAlertAction.Style.default, handler: { (action) in
        alert.dismiss(animated: true, completion: nil)
        completion(true)
    }))
    alert.addAction(UIAlertAction(title: "No", style: UIAlertAction.Style.cancel, handler: { (action) in
        alert.dismiss(animated: true, completion: nil)
        completion(false)
    }))
    self.present(alert, animated: true, completion: nil)
}

/// Will quit the application with animation
func quit() {
    UIApplication.shared.perform(#selector(NSXPCConnection.suspend))
    /// Sleep for a while to let the app goes in background
    sleep(2)
    exit(0)
}

Usage:

self.askForQuit { (canQuit) in
     if canQuit {
         self.quit()
     }
}