如何在Swift 2/AVPlayer中恢复背景音频？

Question

我正在学习Swift作为我的第一门编程语言.

中断后我已经挣了好几个小时才恢复背景音频播放(例如通话)

会发生什么:

1. 当应用程序转到后台时,音频会继续播放(工作)
2. 当被呼叫中断时,开始通知中断(工作)
3. 通话结束时,获取中断结束通知(有效)
4. 继续播放音频(不起作用 - 什么都听不到)

非常感谢任何帮助!谢谢

笔记:

1. 该应用程序已注册为背景音频,并在中断前播放正常
2. 我已经尝试过,没有时间延迟恢复播放 - 两个都没有工作

码:

import UIKit
import AVFoundation

var player: AVQueuePlayer!

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        do {
            try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback)
            try AVAudioSession.sharedInstance().setActive(true, withOptions: .NotifyOthersOnDeactivation)
        } catch { }
        let songNames = ["music"]
        let songs = songNames.map { AVPlayerItem(URL:
            NSBundle.mainBundle().URLForResource($0, withExtension: "mp3")!) }
        player = AVQueuePlayer(items: songs)

        let theSession = AVAudioSession.sharedInstance()
        NSNotificationCenter.defaultCenter().addObserver(self,
            selector:"playInterrupt:",
            name:AVAudioSessionInterruptionNotification,
            object: theSession)

        player.play()
    }

    func playInterrupt(notification: NSNotification) {

        if notification.name == AVAudioSessionInterruptionNotification
            && notification.userInfo != nil {

            var info = notification.userInfo!
            var intValue: UInt = 0
            (info[AVAudioSessionInterruptionTypeKey] as! NSValue).getValue(&intValue)
            if let type = AVAudioSessionInterruptionType(rawValue: intValue) {
                switch type {
                case .Began:
                    print("aaaaarrrrgggg you stole me")
                    player.pause()

                case .Ended:
                    let timer = NSTimer.scheduledTimerWithTimeInterval(3, target: self, selector: "resumeNow:", userInfo: nil, repeats: false)
                }
            }
        }
    }
    func resumeNow(timer : NSTimer) {
        player.play()
        print("attempted restart")
    }
}

Answer 1

终于明白了！

解决方案：通过将setCategory行更改为添加了mixable选项：

AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback,
                                            withOptions: .mixWithOthers )