ios - 如何停止从另一个 ViewController 播放音频？

Question

我在 xcode 中创建了四个 ViewController，当按下播放按钮时，每个 ViewController 都会播放不同的音频。如果我导航到另一个 View Controller 并按下该播放按钮...如何停止所有其他音频的播放，并确保新的音频混合成功播放？

下面详述的相同代码存在于四个 ViewController 中。唯一的区别是我创建了三个新的 musicPlayer 实例。它们是 musicPlayerSummer、musicPlayerWinter、musicPlayerAutumn。我为每个 View Controller 创建了新按钮。

如有任何建议，我们将不胜感激。

谢谢

导入 UIKit导入 AVFoundation

类 ViewControllerSpring: UIViewController {

var musicPlayer: AVAudioPlayer!
var mySongs = ["1", "2", "3", "4"]



override func viewDidLoad() {
    super.viewDidLoad()


    initAudio()


    // Do any additional setup after loading the view.

func initAudio() {



    let path = NSBundle.mainBundle().pathForResource(mySongs[0], ofType: "mp3")!

    do {

        musicPlayer = try AVAudioPlayer(contentsOfURL: NSURL(string: path)!)
        musicPlayer.prepareToPlay()
        musicPlayer.numberOfLoops = -1



    } catch let err as NSError {
       print(err.debugDescription)


    }




    let session:AVAudioSession = AVAudioSession.sharedInstance()

    do {
        try session.setCategory(AVAudioSessionCategoryPlayback)
    } catch {
        //catching the error.
    }

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}


/*
// MARK: - Navigation

// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
}
*/

override func prefersStatusBarHidden() -> Bool {
    return true
}






@IBAction func springPlayPressed(sender: UIButton) {

    if musicPlayer.playing {

        musicPlayer.stop()


        // for normal state
        sender.setImage(UIImage(named: "play.png"), forState: UIControlState.Normal)


    } else {

        musicPlayer.play()





        // for Highlighted state
        sender.setImage(UIImage(named: "Pause.png"), forState: UIControlState.Normal)
    }
}

Answer 1

为了解决这个问题，在appDelegate中声明audioPlayer

// inside AppDelegate
var audioPlayer : AVAudioPlayer? = nil

然后简单地在你的 viewController 中声明:

var audioPlayer : AVAudioPlayer? {
    get {
        let appDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
        return appDelegate.audioPlayer
    }
    set {
        let appDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
        appDelegate.audioPlayer = newValue
    }
}