AVPlayer 播放在线资源但不播放相同的下载资源

AVPlayer plays online resource but not same downloaded resource

我从服务器下载了一个音频文件到我的文档目录。我正在尝试在 swift 中使用 AVPlayer 播放相同内容,但由于某些原因无法这样做。下面是我的全部代码。如果我们将 localAudioPath 替换为 onlineResource,它可以正常播放

import UIKit
import AVFoundation

class AudioController: UIViewController {

  var player : AVPlayer!

  override func viewDidLoad() {
    super.viewDidLoad()
  }

  @IBAction func playAudio(sender: AnyObject) {
    var name = "bell.mp3"
    var docs = NSSearchPathForDirectoriesInDomains(directory, .UserDomainMask, true)[0] as! String
    var localAudioPath = docs.stringByAppendingPathComponent(name)
    var onlineResource = "path/to/online/bell.mp3"

    if NSFileManager.defaultManager().fileExistsAtPath(localAudioPath!) {
      let playerItem = AVPlayerItem(URL: NSURL(string: localAudioPath!)!)
      player = AVPlayer(playerItem: playerItem)
      player.play()

    } else {
       /* Alamo fire code to download file to docs directory*/
      let destination = Request.suggestedDownloadDestination(directory: .DocumentDirectory, domain: .UserDomainMask)

      Alamofire.download(.GET, NSURL(string: audio.audioUrl)!.http, destination)
        .progress { (bytesRead, totalBytesRead, totalBytesExpectedToRead) in
        println(totalBytesRead)
      }
       .response { (request, response, _, error) in
        println(response)
      }
   }
  }

}

谁能告诉我是否可以使用 AVPlayer 播放本地文件?

您应该使用 fileURLWithPath: 来提供正确的 url,它应该可以很好地播放本地 url。

let playerItem = AVPlayerItem(URL: NSURL(fileURLWithPath: localAudioPath!)!)