Swift：在avqueueplayer中播放完毕后重播视频

Posted 2023-02-23

【中文标题】Swift：在avqueueplayer中播放完毕后重播视频

【英文标题】：Swift: Replay video after finished playing in avqueueplayer

【发布时间】：2018-08-06 16:19:57

【问题描述】：

我想在 swift 4 和 xcode 9 的应用程序中一个接一个地播放多个视频。我可以使用 avqueue 播放器来做到这一点。但是一旦播放器完成播放所有视频，则无法重播播放器。只是出现一个空白屏幕。

代码：

var selectedVideos : NSMutableArray = []
var videoPlayer: AVQueuePlayer!
var playerLayer: AVPlayerLayer!
var videoQueue: [AVPlayerItem] = []
var currentVideoTime: Double = 0
var previousVideoTime: Double = 0
var total_video_duration: Double = 0.0;
var total_video: Int = 0

@IBOutlet weak var video_container: UIView!
@IBOutlet weak var video_duration: UILabel!

override func viewDidLoad() 
    super.viewDidLoad()

    setup_video_player()
    setup_layer()

    NotificationCenter.default.addObserver(self, selector: #selector(self.finishVideo), name: NSNotification.Name.AVPlayerItemDidPlayToEndTime, object: nil)



func setup_video_player() 

    try! AVAudiosession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback, with: [])

    currentVideoTime = 0
    previousVideoTime = 0
    total_video_duration = 0
    video_duration.text = "00:00"
    videoPlayer = nil
    videoQueue = []
    total_video = selectedVideos.count

    var playerItem: AVPlayerItem!

    for index in selectedVideos 

        print("selected url: \(index as! URL)")
        playerItem = AVPlayerItem(url: index as! URL)
        videoQueue.append(playerItem)
    

    videoPlayer = AVQueuePlayer(items: videoQueue)

    for playerItem in self.videoPlayer.items() 

        let duration = playerItem.asset.duration
        let seconds = CMTimeGetSeconds(duration)
        total_video_duration = total_video_duration + seconds
    

    let interval = CMTime(seconds: 1, preferredTimescale: 2)

    timeObserver = videoPlayer.addPeriodicTimeObserver(forInterval: interval, queue: DispatchQueue.main, using:  elapsedTime in

        self.currentVideoTime =  self.previousVideoTime + CMTimeGetSeconds(elapsedTime)
        self.video_duration.text = self.video_duration(value: self.currentVideoTime)
    )

    print("finish setup video palyer")

    play_video()


func setup_layer() 

    if(playerLayer != nil)

        playerLayer.removeFromSuperlayer()
    

    playerLayer = AVPlayerLayer(player: videoPlayer)
    playerLayer.frame = video_container.bounds
    video_container.layer.addSublayer(playerLayer)

    print("finish setup layer ")


func play_video() 

    if videoPlayer == nil 

        return
    

    videoPlayer.play()
    videoPlayer.volume = 1.0
    print("playing video")


@objc func finishVideo(_ notification: NSNotification) 

    previousVideoTime = currentVideoTime

    print("current video time: \(currentVideoTime)")
    print("total video duration: \(total_video_duration)")

    if Int(currentVideoTime) != Int(total_video_duration) 

        return
    

    play_video()

没有错误。但是无法理解为什么avqueue播放器在播放完一次后不重新播放。

【参考方案1】：

通过查看documentation，我发现没有直接的方法可以循环遍历AVQueuePlayer中的所有AVPlayerItem。您可以使用 AVPlayerLooper 重复一个 AVPlayerItem，但不能重复整个播放器列表。

你可以做的是：

在finished方法中检查您自己的计数器，当它到达结束时，您可以使用函数removeAllItems()删除现有的播放器项目并将[AVPlayerItem]重新分配给您的AVQueuePlayer实例。

希望对你有帮助。