今天遇到一個ios播放聲音中斷后臺音樂的問題，在我的app中如果調用AVAudiosession 播放完聲音，后臺的QQ音樂偶爾不能恢復，而網易云音樂一次都不能恢復播放，研究了一下AVAudioSession ，我之前調用[audioSession setActive:NO error:&err];還有一個方法

/* Set the session active or inactive. Note that activating an audio session is a synchronous (blocking) Operation.

 Therefore, we recommend that applications not activate their session from a thread where a long blocking operation will be PRoblematic.

 Note that this method will throw an exception in apps linked on or after iOS 8 if the session is set inactive while it has running or 

 paused I/O (e.g. audio queues, players, recorders, converters, remote I/Os, etc.).

*/

- (BOOL)setActive:(BOOL)active error:(NSError **)outError;

- (BOOL)setActive:(BOOL)active withOptions:(AVAudioSessionSetActiveOptions)options error:(NSError **)outError NS_AVAILABLE_IOS(6_0);

而AVAudioSessionSetActiveOptions這個枚舉

/*  options for use when calling setActive:withOptions:error: 

AVAudioSessionSetActiveOptionNotifyOthersOnDeactivation -- 

Notify an interrupted app that the interruption has ended and it may resume playback. Only valid on 

session deactivation. */

typedef NS_OPTIONS(NSUInteger, AVAudioSessionSetActiveOptions)

{

AVAudioSessionSetActiveOptionNotifyOthersOnDeactivation = 1

} NS_AVAILABLE_IOS(6_0);

注釋的意思是：“通知中斷程序中斷已經結束，可以恢復播放。。。。“，

 之后改成調用   [[AVAudioSession sharedInstance] setActive:NO withOptions:AVAudioSessionSetActiveOptionNotifyOthersOnDeactivation error:nil];果然網易云音樂也可以恢復了，看了蘋果官方的文章，上面有張圖