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

Question

这个问题已经在 SO 上得到回答。这是参考：

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)

我无法在 14 天后实现它。虽然，它来自随机数据。有人可以检查代码有什么问题吗？

更新：

根据您的建议 (https://stackoverflow.com/a/46072497/7408802)，这是最终的有效代码！

//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)
}

Answer 1

使用简单的UNNotificationTriggers 无法实现您想要实现的目标。对于每两周重复一次的通知，您需要设置一个UNTimeIntervalNotificationTrigger 和一个相当于两周的timeInterval。但是，您不能指定时间间隔触发器的第一个触发日期，它会在您安排后立即开始“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。

您需要首先为用户指定的日期设置一个不重复的UNCalendarNotificationTrigger，并在发送通知后设置一个每两周触发一次的UNTimeIntervalNotificationTrigger。这种方法的唯一问题是用户也会在指定日期看到通知，而不仅仅是在那之后的每两周一次。但是，您可以通过将通知设置为在指定日期后两周发送通知来规避此问题，这样用户就不会注意到通知之间的差异。

Answer 2

@David 的回答非常正确。我想在这里添加一件事。如果用户不会点击通知，则您无法安排其他通知。您可以为此使用后台获取。如果 IOS 触发后台获取，则检查当前日期与您的计划日期并生成新通知。