如何检测耳机按键？

Question

我想检测用户是否按下了耳机键，因为我使用了2种方法。

-(void)headsetMicrophoneDetection 
{ 
    [[UIApplication sharedApplication] beginReceivingRemoteControlEvents]; 
    [[MPRemoteCommandCenter sharedCommandCenter].togglePlayPauseCommand addTarget:self action:@selector(onTooglePlayPause)]; 

    NSLog(@"calling headset method"); 
} 
-(void)onTooglePlayPause 
{ 
    NSLog(@"kishore"); 
} 
- (void)remoteControlReceivedWithEvent:(UIEvent *)theEvent 
{ 
    NSLog(@"callig method to :)"); 
    if (theEvent.type == UIEventTypeRemoteControl) { 
     switch(theEvent.subtype) { 
      case UIEventSubtypeRemoteControlTogglePlayPause: 
       NSLog(@"Hello"); 
       break; 
      case UIEventSubtypeRemoteControlPlay: 
       NSLog(@"Hello 2"); 
       break; 
      case UIEventSubtypeRemoteControlPause: 
       NSLog(@"Hello 3"); 
       break; 
      case UIEventSubtypeRemoteControlStop: 
       NSLog(@"Hello 4"); 
       break; 
      default: 
       return; 
     } 
    } 
} 

但调用此方法余did't得到的，什么是错在我的代码和我启用后台服务，为音频检查&我使用这NSObject类的所有方法之后。

Answer 1

请检查以下代码。

- (BOOL)isHeadsetPluggedIn { 
    AVAudioSessionRouteDescription* route = [[AVAudioSession sharedInstance] currentRoute]; 
    for (AVAudioSessionPortDescription* desc in [route outputs]) { 
     if ([[desc portType]  isEqualToString:AVAudioSessionPortHeadphones]) 
      return YES; 
    } 
    return NO;}