每 14 天（每两周）触发一次 UILocalNotification Swift

这个问题已经在SO上得到了回答。这是参考：

iOS 通知触发：每两周和/或每季度 https://stackoverflow.com/questions/41441124/ios-notification-trigger-fortnightly-and-or-quarterly

但到目前为止我已经尝试过：

var fortnightPart1 = DateComponents()
fortnightPart1.weekday = Calendar.current.component(.day, from: Sdate) //(Day..here Sunday)
fortnightPart1.weekdayOrdinal = 2 //= n == (nth Day in the month...here 2nd Sunday in every month month)
fortnightPart1.hour = Calendar.current.component(.hour, from: Sdate)
fortnightPart1.minute = Calendar.current.component(.minute, from: Sdate)
fortnightPart1.second = Calendar.current.component(.second, from: Sdate)
trigger = UNCalendarNotificationTrigger(dateMatching: fortnightPart1, repeats: repeate)

14天后我无法实现它。虽然，它来自随机数据。有人可以检查一下代码有什么问题吗？

Update:

根据您的建议（https://stackoverflow.com/a/46072497/7408802 https://stackoverflow.com/a/46072497/7408802），这是最终有效的代码！

//for 1st time notification
 let center = UNUserNotificationCenter.current()
 let content = UNMutableNotificationContent()
 content.title = title
 content.body = body
 content.categoryIdentifier = "\(id)"
 content.sound = UNNotificationSound.default()
 fortnightPart1.hour = Calendar.current.component(.hour, from: dateToFireON)
 fortnightPart1.minute = Calendar.current.component(.minute, from: dateToFireON)
 fortnightPart1.second = Calendar.current.component(.second, from: dateToFireON)
 trigger = UNCalendarNotificationTrigger(dateMatching: fortnightPart1, repeats: false)
 content.userInfo = ["NotificationID": id,"repeate":repeate,"resedule":true]
 let request = UNNotificationRequest(identifier: "\(id)", content: content, trigger: trigger)
 center.add(request)

//when first notification triggered, we need to set another for 14 days repeat in UIApplicationDelegate
func application(_ application: UIApplication, didReceive notification: UILocalNotification) {
    let center = UNUserNotificationCenter.current()
    let content = UNMutableNotificationContent()
    content.title = notification.alertTitle!
    content.body = notification.alertBody!
    content.categoryIdentifier = "\(reminderId)"
    content.userInfo = ["NotificationID": reminderId,"repeate":true,"resedule":false]
    content.sound = UNNotificationSound.default()
    let trigger = UNTimeIntervalNotificationTrigger.init(timeInterval: 1209600, repeats: true)
    let request = UNNotificationRequest(identifier:"\(reminderId)", content: content, trigger: trigger)
    center.add(request, withCompletionHandler: nil)
}

使用简单的方法无法实现您想要实现的目标UNNotificationTriggers。要每两周重复一次通知，您需要设置UNTimeIntervalNotificationTrigger with a timeInterval相当于两周。但是，您无法指定时间间隔触发器的第一个触发日期，一旦您安排它，它就会开始“滴答”。

另一方面，UNCalendarNotificationTrigger可以安排在特定日期触发，但这样做的问题是您无法为通知触发器指定自定义重复间隔。

您需要首先设置一个不重复的UNCalendarNotificationTrigger在用户指定的日期，一旦发送通知，设置一个UNTimeIntervalNotificationTrigger每两周触发一次。这种方法的唯一问题是用户也会在指定日期看到通知，而不仅仅是此后每两周一次。但是，您可以通过将通知设置为在指定日期后两周发送来规避此问题，这样用户就不会注意到通知之间的差异。