How to know when user made change to settings bundle

Question

I let the user make changes to their settings in the settings area of the iphone. During the next network sync i\'d like to send the user changes to the server. But only if the

Answer 1

Swift

Observe for changes and call a method on change:

NotificationCenter.default.addObserver(
    self,
    selector: #selector(updateStateFromSettingsBundle),
    name: UserDefaults.didChangeNotification,
    object: nil
)

@objc func updateStateFromSettingsBundle() {}