监测手机扬声器是否打开

         [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(routeChange:) name:AVAudioSessionRouteChangeNotification object:nil];

/**

 监测外音变化

 @param notification 通知可以得到很多信息

 */

-(void)routeChange:(NSNotification*)notification{

    NSArray* outputs = [[AVAudioSession sharedInstance] currentRoute].outputs;

    AVAudioSessionPortDescription* portDescription = [outputsfirstObject];

    DebugLog(@"port Description:%@", portDescription);

    if([portDescription.portTypeisEqualToString:@"Headphones"]) {//耳机

    }elseif([portDescription.portTypeisEqualToString:@"Speaker"]) {//扬声器

        [self setSpeakerButtonState:YES];

    }elseif([portDescription.portTypeisEqualToString:@"Receiver"]) {//小声

        [self setSpeakerButtonState:NO];

    }

//    }

}