ios - 根据通知数量增加角标(Badge)值

Question

我在我的应用程序中显示通知，但我无法根据通知数量增加角标(Badge)编号。我的代码如下:

func notifcation(model: Model) -> Void {
    let calendar = Calendar.current
    guard let date = model.remiderDate else {return}
    let title = model.name
    let body = model.desc
    let comp2 = calendar.dateComponents([.year,.month,.day,.hour,.minute], from: date)
    let trigger = UNCalendarNotificationTrigger(dateMatching: comp2, repeats: true)
    let content = UNMutableNotificationContent()
    content.title = title
    content.body = body
    content.sound = UNNotificationSound.default()
    content.badge = UIApplication.shared.applicationIconBadgeNumber + 1 as NSNumber

    let identifier = "\(date)"
    let request = UNNotificationRequest(identifier: identifier,
                                        content: content, trigger: trigger)


    center.add(request, withCompletionHandler: { (error) in
        if let error = error {
            // Something went wrong
            print(error as Any)
        }
    })
}

我能够收到多个通知，但无法增加角标(Badge)值以反射(reflect)通知数量。

如果应用程序当前正在运行，应用程序通知也不会显示，但如果应用程序在后台，则通知有效。

Answer 1

你可以使用这个增加角标(Badge):

UIApplication.shared.applicationIconBadgeNumber += 1

或者:

content.badge = NSNumber(integerLiteral: UIApplication.shared.applicationIconBadgeNumber + 1)

要在应用程序处于前台时接收通知，您的 View Controller 应符合 UNUserNotificationCenterDelegate 协议(protocol)并实现 userNotification:willPresent 方法，然后声明您的 View Controller 作为 viewDidLoad() 中的通知委托(delegate):

class ViewController: UIViewController, UNUserNotificationCenterDelegate {
    override func viewDidLoad() {
        super.viewDidLoad()
        //...
        UNUserNotificationCenter.current().delegate = self
    }

    func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
        completionHandler([.alert, .sound])
    }
}

有关本地通知的更多信息，请查看 here .