iphone开发怎么后台播放音频

1、在程序播放音频前，添加下面代码

NSError *myErr = nil;

AVAudioSession *audioSession = [AVAudioSession sharedInstance];

BOOL bAudioInputAvailable = [audioSession inputIsAvailable];

 

if (bAudioInputAvailable)

{ 

   [audioSession setCategory:AVAudioSessionCategoryPlayAndRecord error:&myErr];

}    

else

{

   [audioSession setCategory:AVAudioSessionCategoryPlayback error:&myErr];

}

2、在info.plist文件中添加Requried background modes，属性值为App plays audio