<CoreLocation/CoreLocation.h>框架

#import <UIKit/UIKit.h>
#import <CoreLocation/CoreLocation.h>
@interface ViewController : UIViewController<CLLocationManagerDelegate>@property (retain, nonatomic) UIImageView *compassImageView;
@property (retain, nonatomic) CLLocationManager *locationManager;
@end

ViewController.m代码如下：

- (void)viewDidLoad
{[super viewDidLoad];UIImageView* backgroundImage = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"BackGroundPad.png"]];[self.view addSubview:backgroundImage];//创建指南针图片self.compassImageView = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"Compass_HD.png"]];self.compassImageView.center = CGPointMake(370, 500);[self.view addSubview:self.compassImageView];//初始化locationManager并设置代理类self.locationManager = [[CLLocationManager alloc]init];self.locationManager.delegate = self;if ([CLLocationManager headingAvailable]) {//设置精度self.locationManager.desiredAccuracy = kCLLocationAccuracyBest;//设置滤波器不工作self.locationManager.headingFilter = kCLHeadingFilterNone;//开始更新[self.locationManager startUpdatingHeading];}else{UIAlertView *alert=[[UIAlertView alloc]initWithTitle:@"atention" message:@"compass not Available" delegate:nil cancelButtonTitle:@"OK" otherButtonTitles: nil];[alert show];}
}

//调用locationManager成员方法
- (void)locationManager:(CLLocationManager *)manager didUpdateHeading:(CLHeading *)newHeading{//重置view的位置self.compassImageView.transform = CGAffineTransformIdentity;      CGAffineTransform transform = CGAffineTransformMakeRotation(-1 * M_PI*newHeading.magneticHeading/180.0);self.compassImageView.transform = transform;
}

这样就OK啦 ！ 要在真机上测试哦！！！