如何检测 AVPlayer 实际上开始在 swift 中播放

Question

您好，我已将 UISliderminimum 值设置为 0.00。然后我以这种方式设置它的最大值。

self.viewPlayer.layer.addSublayer(playerLayer)
    let duration : CMTime = avPlayer.avPlayer.currentItem!.asset.duration
    let seconds : Float64 = CMTimeGetSeconds(duration)

    sliderBar.maximumValue=Float(seconds)
    sliderBar!.isContinuous = false
    sliderBar!.tintColor = UIColor.green

但是我遇到了这个异常

*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Attempting to set a slider's minimumValue (0.000000) to be larger than the maximumValue (nan)'
enter code here

我知道在prepareForPlay() 到实际播放之后，真正播放视频需要一些时间。那么如何检测播放器何时真正开始播放视频呢？ 请帮我。 谢谢

Answer 1

超级简单的 SWIFT 4-5 解决方案：

只需检查timeControlStatus!:（也适用于 PlayerQueue）

    if avPlayer?.timeControlStatus.rawValue == 2 {
       
    //video is playing (playing)

    } else if avPlayer?.timeControlStatus.rawValue == 0 { 
    
    //video is not playing (paused)
    
    }

原始值将为您提供其当前状态:)

Answer 2

另一种更简单的方法类似于：

if videoPlayer.rate != 0 && videoPlayer.error == nil {
            print("video player is playing.................")
        } else {
            print("video player is NOT playing.")
        } 

videoPlayer 显然是 AVPlayer 类型。

Answer 3

声明 AVPlayer 全局

var streamPlayer = AVPlayer()

func playStreamAudio( for audioUrl:String)
    {
        guard streamPlayer.timeControlStatus != .playing else {
            streamPlayer.pause()
            return
        }
        let url = audioUrl //"http://192.168.71.11:7891/rec.wav"
        let playerItem = AVPlayerItem(url: URL(string:url)!)
        streamPlayer = AVPlayer(playerItem:playerItem)
        streamPlayer.rate = 1.0;
        streamPlayer.volume = 1.0
        streamPlayer.play()
    }

Answer 4

从 iOS 10 开始，您可以观察到 AVPlayer 的 timeControlStatus 属性。可以是.playing。

查看代码：

private func setupAVPlayer() {
    avPlayer.addObserver(self, forKeyPath: "status", options: [.old, .new], context: nil)
    if #available(iOS 10.0, *) {
        avPlayer.addObserver(self, forKeyPath: "timeControlStatus", options: [.old, .new], context: nil)
    } else {
        avPlayer.addObserver(self, forKeyPath: "rate", options: [.old, .new], context: nil)
    }
}

override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
    if object as AnyObject? === avPlayer {
        if keyPath == "status" {
            if avPlayer.status == .readyToPlay {
                avPlayer.play()
            }
        } else if keyPath == "timeControlStatus" {
            if #available(iOS 10.0, *) {
                if avPlayer.timeControlStatus == .playing {
                    videoCell?.muteButton.isHidden = false
                } else {
                    videoCell?.muteButton.isHidden = true
                }
            }
        } else if keyPath == "rate" {
            if avPlayer.rate > 0 {
                videoCell?.muteButton.isHidden = false
            } else {
                videoCell?.muteButton.isHidden = true
            }
        }
    }
}

Answer 5

来自 Apple 的docs： You can observe an AVPlayerLayer object’s readyForDisplay property to be notified when the layer has user-visible content. In particular, you might insert the player layer into the layer tree only when there is something for the user to look at and then perform a transition from

Answer 6

这是我实际知道视频开始（而不是刚刚准备开始）时所做的。

斯威夫特 4

player = AVPlayer(url: URL(fileURLWithPath: path))
player.addObserver(self, forKeyPath: "rate", options: NSKeyValueObservingOptions.new, context: nil)

override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
    if keyPath == "rate" {
        if player.rate > 0 {
            print("video started")
        }
    }
}

Answer 7

你可以像这样在你的 AVPlayer 的对象上添加一个观察者

player.addObserver(self, forKeyPath: "status", options: NSKeyValueObservingOptions.new, context: nil)

你可以像这样用你的 AVPlayer 检查状态变化

 func observeValueForKeyPath(keyPath: String?, ofObject object: AnyObject?, change: [String : AnyObject]?, context: UnsafeMutableRawPointer) {
    if keyPath == "status" {
        print(player.status)
    }
}