当其他应用程序在Swift中播放音乐时，将我的应用程序静音

Question

I'm writing an app that plays music. However, I'd like to make it so that my app's music pauses when other music is playing, such as music from iTunes. How would I accomplish this? Here's my code:

 var alertSound = NSURL(fileURLWithPath: NSBundle.mainBundle().pathForResource("Ambler", ofType: "mp3")!)

    // Removed deprecated use of AVAudioSessionDelegate protocol
    AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryAmbient, error: nil)
    AVAudioSession.sharedInstance().setActive(true, error: nil)

    var error:NSError?
    audioPlayer = AVAudioPlayer(contentsOfURL: alertSound, error: &error)
    audioPlayer.prepareToPlay()
    audioPlayer.play()
    audioPlayer.numberOfLoops = -1

Answer 1

To do this I believe you are going to need to check if the music player is playing, here is how I would do that in Objective-C.

First #import <MediaPlayer/MediaPlayer.h> and add the library to your build phases.

- (BOOL)isPlaying
{
    MPMusicPlayerController *musicPlayer = [MPMusicPlayerController systemMusicPlayer];
    if (musicPlayer.playbackState == MPMusicPlaybackStatePlaying) {
        return YES;
    }
    return NO;
}

When initializing musicPlayer it may cause the music to stop, if so I would look into

+ (MPMusicPlayerController *)applicationMusicPlayer

Swift

func isPlaying() -> Bool {

    let musicPlayer = MPMusicPlayerController.systemMusicPlayer()
    if musicPlayer.playbackState == MPMusicPlaybackState.Playing {
        return true
    }
    return false
}