在一定时间后隐藏NSUserNotification

使用NSObject的performSelector:withObject:afterDelay:方法实际上很简单 。

由于您要在一定时间间隔后安排通知传递，因此需要在解除之前将附加延迟添加到传递之前的初始延迟中。在这里，我已将它们写为交货前10秒和解雇前2秒的常量：

let delayBeforeDelivering: NSTimeInterval = 10
let delayBeforeDismissing: NSTimeInterval = 2

let notification = NSUserNotification()
notification.title = "Title"
notification.deliveryDate = NSDate(timeIntervalSinceNow: delayBeforeDelivering)

let notificationcenter = NSUserNotificationCenter.defaultUserNotificationCenter()

notificationcenter.scheduleNotification(notification)

notificationcenter.performSelector("removeDeliveredNotification:",
    withObject: notification,
    afterDelay: (delayBeforeDelivering + delayBeforeDismissing))