swift notification messages manually for app - ios

Question

How to notify the message when manually changes from device notifications from setting
. notifications changes, what method will be invoke inside app, to know that notification was changes
override func awakeFromNib() {
super.awakeFromNib()
let center = UNUserNotificationCenter.current()
center.getNotificationSettings { (settings) in
if(settings.authorizationStatus == .authorized)
{
print(" authorized")
DispatchQueue.main.async {
self.onOffSwitch.isOn = true
}
}
else
{
print(" not authorized")
DispatchQueue.main.async {
self.onOffSwitch.isOn = false
}
}
}
I got tableview inside SettingViewcontroller customize my cell where added the swift onOffSwift.
Based on the setting manually user changes the notifications from setting I wants my app sync accordingly.
SettingViewController
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
tbl_SettingView.reloadData()
}
I expected this will work for me? but not
How to handle when user changes there notifications from setting screen should reflect on mobile app screen.

Answer 1

Your app doesn't get an automatic notification when the settings are changed. But the user can make this change only in the Settings app, so you can check the settings when your app comes back to the foreground.
The reason your
override func viewWillAppear(_ animated: Bool) {
doesn't help is that viewWillAppear is not called when the app comes back to the foreground.

Answer 2

There might be better ways but the one I know is this:
Store Settings.authorizationStatus as value in a singleton class or as an entry in UserDefaults
Whenever the app becomes active compare the new value to the stored value. If the they are not the same than you know the settings were changed

Answer 3

I believe you want to get your updated settings when your app enters foreground and not when viewWillAppear called. Just add the observer to your viewDidLoad() (and don't forget to remove it once you're done with the controller):
NotificationCenter.default.addObserver(forName: UIApplication.willEnterForegroundNotification, object: nil, queue: nil) { _ in
UNUserNotificationCenter.current().getNotificationSettings(completionHandler: { settings in
DispatchQueue.main.async {
// update your view with current settings.authorizationStatus
}
})
}