AVPlayerItem从URL不播放

Question

我试着用Alamofire下载的数据文件播放mp3。这首歌很好，我可以用AVAudioPlayer(data: Data)播放。如何使用AVPlayer播放相同的数据文件？我找不到如何从数据创建PlayerItem或从数据创建AVAsset。另外，我有歌曲路径的url，但是那个URL在某种程度上不适用于AVPlayer。音乐就是不演奏。

func startSong(withIndex: Int) {
    if let item = getItem(atIndex: withIndex) {
        do {
            try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback)
            print("AVAudioSession Category Playback OK")
            do {
                try AVAudioSession.sharedInstance().setActive(true)
                print("AVAudioSession is Active")
            } catch let error as NSError {
                print(error.localizedDescription)
            }
            let playerItem = item
            self.player = AVPlayer(playerItem: playerItem)
        } catch let error as NSError {
            print(error.localizedDescription)
        }
    }
}

func getItem(atIndex: Int) -> AVPlayerItem? {

    var item: AVPlayerItem

    var url: URL

    let song = playlist.getSong(index: atIndex)

    if PlaylistsService.sharedService.isFileDownloaded(inPath: SongPath.Offline(id: (song?.getID())!).path()) {
        url = URL(fileURLWithPath: SongPath.Offline(id: (song?.getID())!).path())
    } else if PlaylistsService.sharedService.isFileDownloaded(inPath: SongPath.Temp(id: (song?.getID())!).path()) {
        url = URL(fileURLWithPath: SongPath.Temp(id: (song?.getID())!).path())
    } else {
        self.downloadSong(song: song!)
        url = URL(fileURLWithPath: SongPath.Temp(id: (song?.getID())!).path())
    }

    item = AVPlayerItem(url: url)

    return item
}

@IBAction func playPause(_ sender: UIButton) {
    sender.isSelected = !sender.isSelected
    if sender.isSelected {
        print("Play")
        self.player.play()
    } else {
        print("Pause")
        self.player.pause()
    }
}

Answer 1

刚刚发现AVPlayerItem不能从指向数据文件的URL创建对象。例如，您需要具有文件扩展名".mp3“的URL。现在，当我将扩展添加到用于下载和播放的路径中时，一切都在正常工作。