UILocalNotification已弃用，因此我想将代码更新为UserNotification框架：

let alertDays = 3.0
let alertSeconds = alertDays * 24.0 * 60.0 * 60.0

let localNotification:UILocalNotification = UILocalNotification()

localNotification.alertAction = "Reminder"
localNotification.alertTitle = "Reminder Title"
localNotification.alertBody = "Reminder Message"
localNotification.fireDate = Foundation.Date(timeIntervalSinceNow: alertSeconds)
localNotification.repeatInterval = .day            
UIApplication.shared().scheduleLocalNotification(localNotification)

等待初始通知后，如何通过UserNotification框架设置类似的每日或每小时重复？

let alertDays = 3.0
let alertSeconds = alertDays * 24.0 * 60.0 * 60.0

let content: UNMutableNotificationContent = UNMutableNotificationContent()

content.title = "Reminder Title"
content.subtitle = "Reminder Subtitle"
content.body = "Reminder Message"

let calendar = Calendar.current

let alarmTime = Foundation.Date(timeIntervalSinceNow: alertSeconds)
let alarmTimeComponents = calendar.components([.day, .hour, .minute], from: alarmTime)

let trigger = UNCalendarNotificationTrigger(dateMatching: alarmTimeComponents, repeats: true)

let request = UNNotificationRequest(identifier: workoutAlarmIdentifier,
                                        content: content,
                                        trigger: trigger)

UNUserNotificationCenter.current().add(request)
    {
        (error) in // ...
    }