Ios 将KVO从推送扩展触发到应用

我正在尝试在主应用程序中实现KVO，并观察扩展何时更改了值。 主应用程序在收到推送时打开，但主应用程序中没有触发器。只有当我关闭并打开它时，我才能看到变化

通知类别：

class NotificationService: UNNotificationServiceExtension {

var contentHandler: ((UNNotificationContent) -> Void)?
var bestAttemptContent: UNMutableNotificationContent?


override func didReceive(_ request: UNNotificationRequest, withContentHandler contentHandler: @escaping (UNNotificationContent) -> Void) {

    self.contentHandler = contentHandler
    bestAttemptContent = (request.content.mutableCopy() as? UNMutableNotificationContent)

    if let bestAttemptContent = bestAttemptContent {

        var user = (bestAttemptContent.userInfo["user"] as! String?)!
        let userDefaults = UserDefaults(suiteName: "group.com.test.apps")
        userDefaults!.set(user as String, forKey: "User")
        userDefaults!.synchronize()
        contentHandler(bestAttemptContent)
    }
}
}

主视图控制器：

class ViewController: UIViewController {

override func viewDidLoad() {
    super.viewDidLoad()

     let userDefaults = UserDefaults(suiteName: "group.com.test.apps")
    userDefaults!.addObserver(self, forKeyPath: "User", options: NSKeyValueObservingOptions.new, context: nil)

}

 override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {

    //Not triggered
    let userDefaults = UserDefaults(suiteName: "group.com.test.apps")
    let user = userDefaults!.string(forKey: "User")
    NSLog("User \(user)")

}
}

---

您是否使用iOS 10或更高版本？跨进程（如扩展）的KVO直到10时才起作用，搜索“Key-Value Observing and NSUserDefaults”

套件的

UserDefault

不是共享实例，因此您必须保留它，否则它将被释放

这里是固定的应用程序端控制器。使用Xcode 11.4/iOS 13.4进行测试

注意：KVO只有在设置了真正的新值时才起作用，因此如果在扩展中您将相等的值设置为UserDefaults，则不会通知观察者

---

我的目标是13.2，根据苹果的文档，我应该在iOS 10之后工作

class ViewController: UIViewController {

  // keep suite instance as member
  let userDefaults = UserDefaults(suiteName: "group.com.test.apps")

  override func viewDidLoad() {
    super.viewDidLoad()

    userDefaults!.addObserver(self, forKeyPath: "User", options: [.new], context: nil)
  }

  override func observeValue(forKeyPath keyPath: String?, of object: Any?, 
       change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {

    let user = userDefaults!.string(forKey: "User")
    NSLog("User \(user)")

  }
}