iphone开发如何后台播放音频

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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