Local notifications repeat interval using calendar triggers

Question

I'm setting up some local notifications as reminders. So far I've been able to set a non repeating notification which triggers from a date picked from a datePicker.

let dateformatter = DateFormatter()
    dateformatter.dateStyle = DateFormatter.Style.medium
    dateformatter.timeStyle = DateFormatter.Style.short
    let dateFromString = dateformatter.date(from: selectDateTextField.text!)
    let fireDateOfNotification: Date = dateFromString!

    //if permission allowed
    let content = UNMutableNotificationContent()
    content.title = notifTitleTextField.text!
    content.body = notifNoteTextView.text
    content.sound = UNNotificationSound.default()

    let triggerDate = Calendar.current.dateComponents([.year,.month,.day,.hour,.minute,.second,], from: fireDateOfNotification)
    let trigger = UNCalendarNotificationTrigger(dateMatching: triggerDate,
                                                repeats: false)
    //Schedule the Notification
    let titleNospace = notifTitleTextField.text?.replacingOccurrences(of: " ", with: "")
    let identifier = titleNospace
    let request = UNNotificationRequest(identifier: identifier!, content: content, trigger: trigger)
    self.center.add(request, withCompletionHandler: { (error) in
        if let error = error {
            print(error.localizedDescription)
        }
    })

Now i would like the user to pick from a list (or a Picker) the repeating interval (hourly, daily, weekly, monthly, yearly or every x days). Is there a simple way to do so or i need to create a custom class? is it correct to make it through a series of if else statement? (it seems to me a bit off, doesn't really seems to be the correct way) Thanks.

Answer 1

If you set up a UNCalendarNotificatonTrigger, you cannot manipulate its repetition interval when you set repeats = true, since it will be repeating at each date when the date components of the trigger are matched. To give you an example, if you only set up the hour, minute and second components, your notification will be repeated daily, since the exact hour, minute and second values occur each day. If you only set up minute and second, the notification will repeat every hour.

What you are looking for is the UNTimeIntervalNotificationTrigger, this is the one using which you can set up the repetition interval.

However, to match your criteria, you need to mix both triggers. You should first set up a non-repeating UNCalendarNotificationTrigger and once that notification is delivered, set up a repeating UNTimeIntervalNotificationTrigger with the time interval coming from the user. See UNTimeIntervalNotificationTrigger