ios - 如何通过快速按下按钮取消 localNotification？

Question

我正在通过单击按钮安排基于位置的 UILocalNotification。但是当我尝试通过再次单击同一个按钮来取消 localNotification 时，它不会取消通知。我正在使用 UIApplication.sharedApplication().cancelLocalNotification(localNotification)取消我预定的基于位置的本地通知。我究竟做错了什么 ？这是我的实现

@IBAction func setNotification(sender: UIButton!) {
    if sender.tag == 999 {
        sender.setImage(UIImage(named: "NotificationFilled")!, forState: .Normal)
        sender.tag = 0
        regionMonitor() //function where notification get scheduled

    } else {
        sender.setImage(UIImage(named: "Notification")!, forState: .Normal)
        sender.tag = 999 }

我应该在 else block 中输入什么，以便取消预定的通知。无法清除所有通知。这是我触发本地通知的 didEnterRegion block 代码

func locationManager(manager: CLLocationManager!, didEnterRegion region: CLRegion!) {
    localNotification.regionTriggersOnce = true
    localNotification.alertBody = "Stack Overflow is great"
    UIApplication.sharedApplication().scheduleLocalNotification(localNotification)
    NSLog("Entering region")
}

Answer 1

如果这在您的上下文中可以接受，您可以尝试删除所有通知。像这样:

for notification in UIApplication.sharedApplication().scheduledLocalNotifications as! [UILocalNotification] { 
  UIApplication.sharedApplication().cancelLocalNotification(notification)
}

或者如 Logan 所述:

UIApplication.sharedApplication().cancelAllLocalNotifications()

或者如 Gerard Grundy 为 Swift 4 所述:

UNUserNotificationCenter.current().removeAllPendingNotificationRequests()