学步园

from :http://blog.csdn.net/sxsoul/article/details/8467836

[[UIDevice currentDevice] setProximityMonitoringEnabled:YES];
//建议在播放之前设置yes，播放结束设置NO，这个功能是开启红外感应

//添加监听
    [[NSNotificationCenter
defaultCenter] addObserver:self
                                             selector:@selector(sensorStateChange:)
                                                 name:@"UIDeviceProximityStateDidChangeNotification"
                                               object:nil];

//处理监听触发事件
-(void)sensorStateChange:(NSNotificationCenter *)notification;
{
    //如果此时手机靠近面部放在耳朵旁，那么声音将通过听筒输出，并将屏幕变暗（省电啊）
    if
([[UIDevice currentDevice] proximityState] == YES)
    {
        NSLog(@"Device
is close to user");
        [[AVAudioSession
sharedInstance] setCategory:AVAudioSessionCategoryPlayAndRecord
error:nil];
       
    }
    else
    {
        NSLog(@"Device
is not close to user");
        [[AVAudioSession
sharedInstance] setCategory:AVAudioSessionCategoryPlayback
error:nil];
    }
}


//初始化播放器的时候如下设置
 UInt32
sessionCategory = kAudioSessionCategory_MediaPlayback;
    AudioSessionSetProperty(kAudioSessionProperty_AudioCategory,
                            sizeof(sessionCategory),