监控耳机事件

-(void)whetherTheHeadsetInsert{
[[AVAudioSession sharedInstance] setActive:YES error:nil];
//创建单例对象并且使其设置为活跃状态.
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(audioRouteChangeListenerCallback:) name:AVAudioSessionRouteChangeNotification object:nil];//设置通知
}
//通知方法的实现

• (void)audioRouteChangeListenerCallback：(NSNotification*)notification {
  NSDictionary *interuptionDict = notification.userInfo;
  NSInteger routeChangeReason = [[interuptionDict valueForKey:AVAudioSessionRouteChangeReasonKey] integerValue];
  switch (routeChangeReason) {

    case AVAudioSessionRouteChangeReasonNewDeviceAvailable:
        NSLog(@"AVAudioSessionRouteChangeReasonNewDeviceAvailable");
        NSLog(@"耳机插入");
        break;
    case AVAudioSessionRouteChangeReasonOldDeviceUnavailable:
        NSLog(@"AVAudioSessionRouteChangeReasonOldDeviceUnavailable");
        NSLog(@"耳机拔出");
        break;
        
    case AVAudioSessionRouteChangeReasonCategoryChange:            // called at start - also when other audio wants to play
        NSLog(@"AVAudioSessionRouteChangeReasonCategoryChange");
        break;
  

  }
  }