检测设备摄像头、指南针、录音、陀螺仪状态

//检查前后摄像头

BOOL cameraAvailable = [UIImagePickerController isCameraDeviceAvailable:UIImagePickerControllerCameraDeviceRear];//前

BOOL frontCameraAvailable = [UIImagePickerController isCameraDeviceAvailable:UIImagePickerControllerCameraDeviceFront];//后

 

//检查指南针 CoreLocation.framework  <CoreLocation/CoreLocation.h>

BOOL magnetometerAvailbale = [CLLocationManager headingAvailable];

 

//检查声音支持 AVFoundation.framework <AVFoundation/AVFoundation.h>

AVAudioSession *audioSession = [AVAudioSession sharedInstance];  //返回一个AVAudioSession实例

BOOL audioAvailable = audioSession.inputAvailable;//bool值。获取是否支持

 

//检查录像支持 MobileCoreServices.framework <MobileCoreServices/MobileCoreServices.h>

- (BOOL)isvideoCameraAvailable

{

    //简单检查所有的可用的媒体资源类型，然后检查返回的数组，如果其中包含了kUTTypeMovie的NSString类型对象，就证明摄像头支持录像

    UIImagePickerController *picker = [[UIImagePickerController alloc]init];

    NSArray *sourceTypes = [UIImagePickerController availableMediaTypesForSourceType:picker.sourceType];//返回所支持的media的类型数组

    [picker release];

 

    if (![sourceTypes containsObject:(NSString *)kUTTypeMovie]) {//containsObject确定数组中是否包含后面的对象

        return NO;

    }

    return YES;

}

     

//检查陀螺仪可用 CoreMotion.framework <CoreMotion/CoreMotion.h>

- (BOOL) isGyroscopeAvailable

{

#ifdef __IPHONE_4_0//4.0之后才有

    CMMotionManager *motionManager = [[CMMotionManager alloc]init];

    BOOL gyroscopeAvailable = motionManager.gyroAvailable;

    [motionManager release];

    return gyroscopeAvailable;

#else

    return NO;

#endif

}