可以通过以下代码示例来解决该问题：

if let player = playerView.player {

player.currentItem?.addObserver(self, forKeyPath: "playbackLikelyToKeepUp", options: .new, context: nil)

NotificationCenter.default.addObserver(self, selector: #selector(itemDidPlayToEnd), name: NSNotification.Name.AVPlayerItemDidPlayToEndTime, object: player.currentItem)

if #available(iOS 11.0, *) {
    
    player.addObserver(self, forKeyPath: "timeControlStatus", options: [.old, .new], context: nil)
}

if UIScreen.main.traitCollection.userInterfaceStyle == .dark {
    
    if #available(iOS 13.0, *) {
        playerView.videoGravity = .resizeAspectFill //.resizeAspect
        player.currentItem?.preferredForwardBufferDuration = 6.0
    } else {
        // Fallback on earlier versions
    }
    
    if #available(iOS 11.0, *) {
        playerView.contentOverlayView?.backgroundColor = UIColor(displayP3Red: 0, green: 0, blue: 0, alpha: 1.0) //.init(white: 1, alpha: 0)
    } else {
        // Fallback on earlier versions
    }
    
} else {
    
    if #available(iOS 13.0, *) {
        playerView.videoGravity = .resizeAspectFill //.resizeAspect
        player.currentItem?.preferredForwardBufferDuration = 6.0
    } else {
        // Fallback on earlier versions
    }
    
    if #available(iOS 11.0, *) {
        playerView.contentOverlayView?.backgroundColor = UIColor(displayP3Red: 1, green: 1, blue: 1, alpha: 1.0) //.init(white: 1, alpha: 0)
    } else {
        // Fallback on earlier versions
    }
}

}