AVAudioSessionInterruptionNotification未正确调用

Question

我正在开发音频流媒体应用，而且我遇到了中断问题。 我已经读过我应该使用AVAudioSessionInterruptionNotification，但我的问题是它只在中断开始时才被调用，而不是在它结束时被调用。 这是我的代码。

static dispatch_once_t pred;
static Player *sharedAudioPlayer = nil;
dispatch_once(&pred, ^
              {
                  sharedAudioPlayer = [[self alloc] init];

                  [[NSNotificationCenter defaultCenter] addObserver:sharedAudioPlayer selector:@selector(playerItemDidFinishPlaying:) name:AVPlayerItemDidPlayToEndTimeNotification object:nil];
                  [[NSNotificationCenter defaultCenter] addObserver:sharedAudioPlayer
                                                           selector:@selector(audioSessionInterrupted:)
                                                               name:AVAudioSessionInterruptionNotification
                                                             object:audioSession];
              });

然后

- (void)audioSessionInterrupted:(NSNotification*)notification {
NSDictionary *interruptionDictionary = [notification userInfo];
NSNumber *interruptionType = (NSNumber *)[interruptionDictionary valueForKey:AVAudioSessionInterruptionTypeKey];
if ([interruptionType intValue] == AVAudioSessionInterruptionTypeBegan) {
    NSLog(@"Interruption started");
    if (self.delegate && [self.delegate respondsToSelector:@selector(playerWasPaused)]) {
        [self.delegate playerWasPaused];
    }
} else if ([interruptionType intValue] == AVAudioSessionInterruptionTypeEnded){
    NSLog(@"Interruption ended");
    [player play];
} else {
    NSLog(@"Something else happened");
}

当一个电话开始时，我会打印两次＆＃34;中断开始＆＃34;但是当它结束时我什么也得不到。我甚至试图检查是否有其他内容发送到通知但仍然没有。 有什么想法吗？