“advanceToNextItem()”不允许循环播放所有视频

我有自动播放序列的视频剪辑与循环行为的基础上建立 KVO . 但是,除了自动播放,我还想使用 NSButton . 所以,如果我按 Next Video 按钮当我的序列自动播放时,此操作将我推进到队列中的下一个剪辑。但这不是一个正确的方法。

:当队列结束时,队列中的所有剪辑都没有循环。只有第一个片段有一个循环(如果我按下 按钮10次 仅第一个剪辑

问题 : ?

这是我的密码:

import Cocoa
import AVFoundation
import AVKit

class ViewController: NSViewController {

    @IBOutlet weak var avPlayerView: AVPlayerView!
    @IBOutlet weak var nextVideoButton: NSButton!
    @objc private let player = AVQueuePlayer()
    let clips = ["One", "Two", "Three", "Four"]
    private var token: NSKeyValueObservation?

    override func viewDidAppear() {
        super.viewDidAppear()
        addAllVideosToPlayer()
    }

    func addAllVideosToPlayer() {
        avPlayerView.player = player
        for clip in clips {
            let urlPath = Bundle.main.path(forResource: clip, ofType: "mov")!
            let url = URL(fileURLWithPath: urlPath)
            let playerItem = AVPlayerItem(url: url)
            player.insert(playerItem, after: player.items().last)

            token = player.observe(\.currentItem) { [weak self] player, _ in
                if self!.player.items().count == 1 { self?.addAllVideosToPlayer() }
            }
            player.play()
            avPlayerView.controlsStyle = .none
        }
    }

    @IBAction func nextVideo(_ sender: Any) {
        var number: Int = 0
        let clip = clips[number]

        let urlPath = Bundle.main.path(forResource: clip, ofType: "mov")!
        let url = URL(fileURLWithPath: urlPath)
        let playerItem = AVPlayerItem(url: url)
        player.insert(playerItem, after: player.items().last)

        player.advanceToNextItem()
        number += 1

        if number >= clips.count {
            number = 0
            player.advanceToNextItem()
            number += 1
        }
    }
}

这是我的ViewController: