我在我的应用程序中使用了 MPMoviePlayerController。我正在尝试获取 MPMoviePlayerController 的完成按钮事件。但是我在 [MPMoviePlayerPlaybackDidFinishReasonUserInfoKey] 中得到的值为 nil，因此应用程序崩溃了。这是我的代码:

// Define notification in class
let notificationName = Notification.Name("moviePlayerDoneButtonClicked")

//---register and  posted notification in viewDidLoad()    

// Register to receive notification
NotificationCenter.default.addObserver(self, selector: #selector(PlayVideo.moviePlayerDoneButtonClicked), name: self.notificationName, object: nil)

// Post notification
NotificationCenter.default.post(name: self.notificationName, object: nil)

//invoking player
playVideo()


//Event for moviePlayer Done Button Pressed (method for notification) 
func moviePlayerDoneButtonClicked(note: NSNotification) {       
    print ("delegate called....")

    let reason = note.userInfo?[MPMoviePlayerPlaybackDidFinishReasonUserInfoKey]
    if (MPMovieFinishReason(rawValue: reason as! Int) == MPMovieFinishReason.userExited) {

        print ("Done button clicked.")
        self.delegate.exitVideoPlayer()
    }
}

//—code for 
func playVideo() {
    //--Adjust height and width of player as per device
    activityIndicator.isHidden = false
    activityIndicator.startAnimating()

    print ("self.attachmentURL : \(self.attachmentURL)")

    DispatchQueue.main.async {
        let url:URL = URL(string: "https://clips.vorwaerts-gmbh.de/big_buck_bunny.mp4")!
        self.moviePlayer = MPMoviePlayerController(contentURL: url)
        self.moviePlayer!.view.frame = CGRect(x: 0, y: 0, width: self.width, height: self.height);
        self.videoContainerView.addSubview(self.moviePlayer!.view)
        self.moviePlayer!.isFullscreen = false
        self.moviePlayer!.controlStyle = MPMovieControlStyle.embedded

        self.activityIndicator.stopAnimating()
        self.activityIndicator.isHidden = true
    }

}

override func viewDidDisappear(_ animated: Bool) {
    // Stop listening notification
    NotificationCenter.default.removeObserver(self, name: notificationName, object: nil);
}

最佳答案

我现在明白你的问题了。您发布的“moviePlayerDoneButtonClicked”通知没有对象，也没有 userInfo 字典。

你为什么要这样做？用户是点击“完成”按钮的人，然后 iOS/电影播放器​​创建“完成”通知供您的应用处理。

删除 NotificationCenter.default.post(name: self.notificationName, ... 那里的行。

并将您的代码更改为:

//Event for moviePlayer Done Button Pressed (method for notification) 
func moviePlayerDoneButtonClicked(notification: NSNotification) {       
    print ("delegate called....")

    if let userInfo = notification.userInfo
    {
        let finishReason = MPMovieFinishReason(rawValue: (notification.userInfo[MPMoviePlayerPlaybackDidFinishReasonUserInfoKey] as! NSNumber).intValue)
        if (finishReason == MPMovieFinishReason.userExited) 
        {
            print ("Done button clicked.")
            self.delegate.exitVideoPlayer()
        }
    } else {
        print("I shouldn't be manually posting a moviePlayerDoneButtonClicked notification without a userInfo dictionary")
    }
}

关于ios - 获取 MPMoviePlayerController 的 MPMoviePlayerPlaybackDidFinishReasonUserInfoKey nil，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/46272587/