检测用户何时将AVPlayer静音

import AVFoundation

class PlayerViewController: UIViewController {
    var player: AVPlayer?

    override func viewDidLoad() {
        super.viewDidLoad()
        
        // 初始化 AVPlayer
        let url = URL(string: "https://example.com/video.mp4")!
        let playerItem = AVPlayerItem(url: url)
        player = AVPlayer(playerItem: playerItem)
        
        // 监听 muted 属性变化
        player?.addObserver(self, forKeyPath: "muted", options: [.new], context: nil)
    }
    
    override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
        if keyPath == "muted" {
            if let isMuted = player?.isMuted, isMuted {
                print("Player is muted")
                // 更新 UI 或执行其他操作
            } else {
                print("Player is not muted")
                // 更新 UI 或执行其他操作
            }
        }
    }
    
    deinit {
        // 移除观察者
        player?.removeObserver(self, forKeyPath: "muted")
    }
}

override func viewDidLoad() {
    super.viewDidLoad()
    // 初始化 AVPlayer 并添加观察者
    player = AVPlayer(playerItem: playerItem)
    player?.addObserver(self, forKeyPath: "muted", options: [.new], context: nil)
}

deinit {
    // 移除观察者
    player?.removeObserver(self, forKeyPath: "muted")
}