12

我有一个使用 AVPlayerLayer 的应用程序（在 UIView 的子类中使用，就像 Apples AV Foundation Programming Guide 一样）。我有几个视图控制器被保存在对菜单负责的视图控制器中（使用了 JASidePanels）。问题如下：

一切正常，直到带有 AVPlayer 的视图控制器没有被隐藏（显示其他视图）并且应用程序进入后台，再次返回并返回视图。这会导致 AVPlayerLayer 显示空白/透明。该项目已加载，我可以尝试播放它，确实它已播放但没有看到视频。

这种行为的解决方案是什么（以及它的原因是什么）？提前谢谢。

4

4 回答 4

2

player?.seek(to: .zero)触发AVPlayerLayer渲染预览。
在我的情况下，为了在关闭/打开应用程序时顺利更新和暂停视频，我添加了以下内容：

private func setupObservers() {
    NotificationCenter.default.addObserver(self, selector: #selector(willResignActive), name: UIApplication.willResignActiveNotification, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(didBecomeActive), name: UIApplication.didBecomeActiveNotification, object: nil)
}

@objc
private func willResignActive() {
    player?.pause()
}

@objc
private func didBecomeActive() {
    player?.seek(to: .zero)
}
于 2020-06-17T13:04:04.663 回答
1

我不确定是什么原因造成的，但对我有用的解决方案是在 AVPlayerLayer 上重置播放器

   avPlayerLayer = AVPlayerLayer(player: currentAvPlayer)
于 2016-02-11T13:58:45.227 回答
0

最后我只是在播放器中重新加载视频文件。

于 2020-09-15T09:10:42.873 回答
0

斯威夫特 3

我有同样的问题。每次我的应用程序进入后台然后回到前台时，我的 AVPlayer 都会消失。下面是一个更简单的代码版本，适用于我……我需要在 UIApplicationWillEnterForeground 上重置播放器。如果您需要，我可以添加更多代码，请告诉我。它现在似乎正在工作。干杯!

import UIKit
import AVFoundation

class ViewController: UIViewController {

    var avPlayer: AVPlayer!
    var avPlayerLayer: AVPlayerLayer!
    var paused: Bool = false

    override func viewDidLoad() {
        super.viewDidLoad()

        // Be sure to add your file to your app (not in the assets folder) and add it to your target
        let theURL = Bundle.main.url(forResource:"yourVideoFile", withExtension: "mp4")

        avPlayer = AVPlayer(url: theURL!)
        avPlayerLayer = AVPlayerLayer(player: avPlayer)

        avPlayerLayer.frame = view.layer.bounds
        avPlayerLayer.videoGravity = AVLayerVideoGravityResizeAspectFill

        // .none is for looping videos if you uncomment "p: AVPlayerItem" below. 
        // .pause is to pause at the end of the video and hold the last frame
        avPlayer.actionAtItemEnd = .pause
        view.layer.insertSublayer(avPlayerLayer, at: 0)

        NotificationCenter.default.addObserver(self, selector: #selector(playerItemDidReachEnd(notification:)), name: NSNotification.Name.AVPlayerItemDidPlayToEndTime,object: avPlayer.currentItem)

        NotificationCenter.default.addObserver(self, selector: #selector(appMovingToForeground), name: Notification.Name.UIApplicationWillEnterForeground, object: nil)

    }

    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)
        avPlayer.play()
        paused = false
    }

    func playerItemDidReachEnd(notification: Notification) {
        print("THE END")

        // uncomment the following line for a looping video
        // let p: AVPlayerItem = notification.object as! AVPlayerItem
        // p.seek(to: kCMTimeZero)

    }

    func appMovingToForeground() {
        print("App moved to foreground!")
        avPlayerLayer = AVPlayerLayer(player: avPlayer)
        view.layer.insertSublayer(avPlayerLayer, at: 0)

        // If you want your video or video loop to continue playing when app moves to foreground add:
        // avPlayer.play()
        // paused = false

    }

}
于 2017-03-15T23:06:19.427 回答