iOS -CoreLocaiton框架之指南针

#import "ViewController.h"

#import@interface ViewController ()/** 位置管理者 */

@property (nonatomic, strong) CLLocationManager *lM;

///指南针iv

@property (weak, nonatomic) IBOutlet UIImageView *compassView;

@end

@implementation ViewController

- (CLLocationManager *)lM

{

if (!_lM) {

_lM = [[CLLocationManager alloc] init];

_lM.delegate = self;

// 每隔多少度更新一次

_lM.headingFilter = 2;

}

return _lM;

}

- (void)viewDidLoad {

[super viewDidLoad];

// 开始监听设备朝向

[self.lM startUpdatingHeading];

}

#pragma mark - CLLocationManagerDelegate

/**

*  获取到手机朝向时调用

*

*  @param manager    位置管理者

*  @param newHeading 朝向对象

*/

-(void)locationManager:(CLLocationManager *)manager didUpdateHeading:(CLHeading *)newHeading

{

/**

*  CLHeading

*  magneticHeading : 磁北角度

*  trueHeading : 真北角度

*/

NSLog(@"%f", newHeading.magneticHeading);

CGFloat angle = newHeading.magneticHeading;

// 把角度转弧度

CGFloat angleR = angle / 180.0 * M_PI;

// 旋转图片

[UIView animateWithDuration:0.25 animations:^{

self.compassView.transform = CGAffineTransformMakeRotation(-angleR);

}];

}