如何在几天前在 UNNotificationCenter 中设置警报？

Question

如何让本地通知提前几天触发？例如，我从 dateComponents:

创建本地通知

    var dateComponents = Calendar.current.dateComponents([.month, .day], from: birthDate)
    dateComponents.hour = 10
    dateComponents.minute = 30
    let trigger = UNCalendarNotificationTrigger(dateMatching: dateComponents, repeats: true)

我的天数来自：

var dateComponents = Calendar.current.dateComponents([.month, .day], from: birthDate).

但是我如何才能将它们设置为在某一天之前的特定时间触发？

Answer 1

if let oneDayAgo = Calendar.current.date(byAdding: .day, value: -1, to: birthDate) {
    var dateComponents = Calendar.current.dateComponents([.month, .day], from: oneDayAgo)
    dateComponents.hour = 10
    dateComponents.minute = 30
    let trigger = UNCalendarNotificationTrigger(dateMatching: dateComponents, repeats: true)
}

如何在几天前在 UNNotificationCenter 中设置警报？

How to set alerts in UNNotificationCenter some days before?

ios

swift

usernotifications