在我的项目中，我使用了 Kolada 视图 (here) 来呈现一堆带有视频的卡片。有时，在加载下一个视频时，我的
更新：我注意到有时候不会调用
AVPlayer 无法播放视频，它只会显示第一帧并且被冻结。我使用了几个观察者来跟踪视频何时实际播放，以及是否可能跟得上播放速度。如果观察者没有正确释放，是否会导致播放停止？如果不是，还有什么其他原因会导致 AVPlayer 的播放停止？更新：我注意到有时候不会调用
playbackLikelyToKeepUp，当发生这种情况时，即使我更改了播放器项目，AVPlayer 也永远不会再次调用它。因此，视频播放永远不会恢复。 init(frame: CGRect, mediaURL: NSURL, thumbURL: NSURL?, isLoop: Bool) {
self.mediaURL = mediaURL
self.isLoop = isLoop
let asset = AVAsset(URL: mediaURL)
let item = AVPlayerItem(asset: asset)
player = AVPlayer(playerItem: item)
player!.actionAtItemEnd = .None
super.init(frame: frame)
asset.loadValuesAsynchronouslyForKeys(["duration"], completionHandler: { () -> Void in
var error: NSError?
let keyStatus: AVKeyValueStatus = asset.statusOfValueForKey("duration", error: &error)
switch (keyStatus) {
case .Loaded:
let duration: CMTime = asset.duration
self.currentDuration = duration
self.delegate?.updateDuration()
default:
break
}
})
NSNotificationCenter.defaultCenter().addObserver(
self,
selector: #selector(MediaPlayerView.playerItemDidReachEnd(_:)),
name: AVPlayerItemDidPlayToEndTimeNotification,
object: player!.currentItem)
self.timeObserver = self.player!.addPeriodicTimeObserverForInterval(CMTimeMakeWithSeconds(1.0 / 30.0, Int32(NSEC_PER_SEC)), queue: nil, usingBlock: {
[weak self] (time) -> Void in
if time.value > 0 {
self?.spinnerView?.stopAnimating()
if(self?.player != nil){
if(self?.player!.rate > 0){
self?.placeholderImageView?.hidden = true
}
}
let timeInSeconds = CMTimeGetSeconds(time)
self?.delegate?.playbackReachedTime(timeInSeconds)
}
})
player!.currentItem?.addObserver(self, forKeyPath: playbackLikelyToKeepUp, options: .New, context: &observationContext)
player!.addObserver(self, forKeyPath: "rate", options: .New, context: &observationContext)
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(MediaPlayerView.playerIsTapped(_:)))
addGestureRecognizer(tapGesture)
}