如何從特定的未來日期起每兩周觸發一次本地通知

Question

我正在嘗試每兩周觸發一次UNUserNotification ，這將從特定的未來日期開始。 我已經使用UNTimeIntervalNotificationTrigger成功觸發了。 但是我的問題是我無法在此處設置特定的開始日期。

UNTimeIntervalNotificationTrigger* trigger = [UNTimeIntervalNotificationTrigger triggerWithTimeInterval:(14*24*3600) repeats: YES];
request = [UNNotificationRequest requestWithIdentifier:identifier content:content trigger:trigger];

我已經嘗試使用WeekdayOrdinal來進行UNCalendarNotificationTrigger但這並不總是與兩周時間完全一樣。

有什么辦法可以讓我從將來的特定日期每兩周安排一次本地UNUserNotification ？

Answer 1

UNNotificationRequest不提供任何觸發兩周重復的功能。

使用UNCalendarNotificationTrigger您只能觸發以下重復類型：

weekly ， daily ， monthly ， yearly

switch repeatType {
    case .daily:
        newComponents.hour = components.hour
        newComponents.minute = components.minute
        break
    case .weekly:
        newComponents.hour = components.hour
        newComponents.minute = components.minute
        newComponents.weekday = components.weekday
        break
    case .monthly:
        newComponents.hour = components.hour
        newComponents.minute = components.minute
        newComponents.day = components.day
        break
    case .none:
        newComponents.hour = components.hour
        newComponents.minute = components.minute
        newComponents.day = components.day
        newComponents.month = components.month
        newComponents.year = components.year
        break
    case .annually:
        newComponents.hour = components.hour
        newComponents.minute = components.minute
        newComponents.day = components.day
        newComponents.month = components.month
        break
    }

盡管您可以輕松地使用EventKit在事件中創建事件和警報，並提供所有您想要的重復選項，例如每兩周，每季度，每半年一次等。

我創建了以下代碼來創建具有多種重復類型的事件：

let eventStore = EKEventStore()
    eventStore.requestAccess(to: .event, completion: { (granted, error) in
        if (granted) && (error == nil) {
            let event = EKEvent(eventStore: eventStore)
            event.title = "Countdown title"
            event.startDate = Date()
            event.notes = "Countdown is complete!"
            event.isAllDay = false

            event.calendar = eventStore.defaultCalendarForNewEvents

            var frequency : EKRecurrenceFrequency = EKRecurrenceFrequency.daily
            var interval = 1

            switch repeatType {
            case .daily:
                //Repeat every day
                frequency = EKRecurrenceFrequency.daily
                interval = 1
                break
            case .weekly:
                //Repeat every week
                frequency = EKRecurrenceFrequency.weekly
                interval = 1
                break
            case .biweekly:
                //Repeat every 2 weeks
                frequency = EKRecurrenceFrequency.weekly
                interval = 2
                break
            case .monthly:
                //Repeat every month
                frequency = EKRecurrenceFrequency.monthly
                interval = 1
                break
            case .quarterly:
                //Repeat every 3 months
                frequency = EKRecurrenceFrequency.monthly
                interval = 3
                break
            case .halfYearly:
                //Repeat every 6 months
                frequency = EKRecurrenceFrequency.monthly
                interval = 6
                break
            default:
                // Repeat every year
                frequency = EKRecurrenceFrequency.yearly
                interval = 1

            }
            let alarm : EKAlarm = EKAlarm(relativeOffset: TimeInterval(exactly: 0)!)
            event.addAlarm(alarm)

            if interval > 0 {
                event.addRecurrenceRule(EKRecurrenceRule(recurrenceWith: frequency, interval: interval, end: nil))
            }

            do {
                try eventStore.save(event, span: .thisEvent)
            } catch let error as NSError {
                print(error.localizedDescription)
                return
            }
        } else {
            print(error?.localizedDescription ?? "no error")
        }
    })

請不要忘記導入EventKit 。

Answer 2

嘗試使用triggerWithDateMatchingComponents方法

Objective-C示例代碼

NSDate *date = [NSDate dateWithTimeIntervalSinceNow:86400]; // You can set your date here.
NSDateComponents *triggerDate = [[NSCalendar currentCalendar]   
              components:NSCalendarUnitYear +
              NSCalendarUnitMonth + NSCalendarUnitDay +
              NSCalendarUnitHour + NSCalendarUnitMinute +
              NSCalendarUnitSecond fromDate:date];

UNCalendarNotificationTrigger *trigger = [UNCalendarNotificationTrigger triggerWithDateMatchingComponents:triggerDate repeats:NO];

迅捷的例子

let triggerDate = Calendar.current.date(byAdding: .day, value: 1, to: self)!
let trigger = UNCalendarNotificationTrigger(dateMatching: triggerDate, repeats: false)