how to stop audio when iOS Sleep Timer gets called

Question

I want to stop my audio app when iOS sleep timer gets called.

Just like Pandora app.
http://help.pandora.com/customer/portal/articles/24324-ios-sleep-timer-with-pandora

Tap the Clock app, Tap Timer, Select a time, Tap When Timer Ends, Tap Stop Playing

This will sleep your Pandora app if it is running.

I can see inInterruptionState == kAudioSessionBeginInterruption gets called when iOS sleep timer ends, but how can I detect if it's sleep timer or just interruptions like phone call?

Here is my codes. Currently, my app just starts playing again after iOS sleep timer ends.

// Audio Interruption Listener
void MyInterruptionListener(void *inClientData, UInt32 inInterruptionState) {

    if (inInterruptionState == kAudioSessionBeginInterruption) {        
        [[DOSpeechManager sharedInstance] audioSessionBeginInterruption];
    }

    if (inInterruptionState == kAudioSessionEndInterruption) {
        [[DOSpeechManager sharedInstance] audioSessionEndInterruption];
    }

}

- (void)audioSessionBeginInterruption {

    if ([_MyAcaTTS isSpeaking] && [_MyAcaTTS isPaused] == NO) {

        [_MyAcaTTS pauseSpeakingAtBoundary:AcapelaSpeechImmediateBoundary];
        [self setAudioSettionStatus:NO];
        _audioInterruptedWhileSpeaking = YES;
    }
}

- (void)audioSessionEndInterruption {

    if (_audioInterruptedWhileSpeaking) {

        [self setAudioSettionStatus:YES];
        [_MyAcaTTS continueSpeaking];
    }
}

- (void)setAudioSettionStatus:(BOOL)status {
    AudioSessionSetActive(status);
    [_MyAcaTTS setActive:status];

    //cancel audio interrupted flag
    if (status) {
        _audioInterruptedWhileSpeaking = NO;
    }
}

Answer 1

The trick is not to detect the source of the interruption, but to know whether your app should resume after the interruption.

The AVAudioSession API will send a notification when the audio session is interrupted. Within this notification, the OS gives a "hint" as to whether the app should resume playback or not.

See below:

    //Add notification observer
    __weak typeof(self) weakSelf = self;
    self.audioSessionInterruptionNotification =
    [[NSNotificationCenter defaultCenter] addObserverForName:AVAudioSessionInterruptionNotification
                                                      object:nil
                                                       queue:[NSOperationQueue mainQueue]
                                                  usingBlock:^(NSNotification *note) {
                                                      NSNumber* interruptionType = note.userInfo[AVAudioSessionInterruptionTypeKey];
                                                      NSNumber* interruptionOption = note.userInfo[AVAudioSessionInterruptionOptionKey];
                                                      BOOL shouldResume = interruptionOption.integerValue == AVAudioSessionInterruptionOptionShouldResume;

                                                      switch (interruptionType.integerValue) {
                                                          case AVAudioSessionInterruptionTypeBegan:
                                                              [weakSelf beginInterruption];
                                                              break;
                                                          case AVAudioSessionInterruptionTypeEnded:
                                                              [weakSelf endInterruption:shouldResume];
                                                              break;
                                                          default:
                                                              break;
                                                      }
                                                  }];
}