一个关于定位的demo

#import "ViewController.h"
#import <MapKit/MapKit.h>

@interface ViewController ()<MKMapViewDelegate>

@property (weak, nonatomic) IBOutlet MKMapView *mapView;

@property (nonatomic, strong) CLLocationManager * manager;

@end

@implementation ViewController

//返回用户当前位置
- (IBAction)currentLocation:(id)sender {
    
    //获取用户所在的经纬度
    CLLocationCoordinate2D coordinate = self.mapView.userLocation.location.coordinate;
    
    MKCoordinateSpan span = MKCoordinateSpanMake(0.1, 0.1);

    MKCoordinateRegion region = MKCoordinateRegionMake(coordinate, span);
    
    //定位可见区域
    [self.mapView setRegion:region animated:YES];
}

- (CLLocationManager *)manager {
    
    if (!_manager) {
        
        //创建定位管理器
        CLLocationManager * locationManager = [[CLLocationManager alloc] init];
        //定位的精确度，精确度越高越耗电
        locationManager.desiredAccuracy = kCLLocationAccuracyBest;
        //定位的更新频率，单位为米
        locationManager.distanceFilter = 5;
        
        _manager = locationManager;
    }
    return _manager;
}

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    
    
    //iOS8的做法
    
    if (![CLLocationManager locationServicesEnabled]) {
        
        NSLog(@"提示用户打开定位服务");
    } else {
        
        //获取当前定位的状态
        CLAuthorizationStatus status = [CLLocationManager authorizationStatus];
        //如果定位状态为未打开
        if (status == kCLAuthorizationStatusNotDetermined) {
            
            //requestWhenInUseAuthorization  前端定位
            //requestAlwaysAuthorization 前端和后台定位
            
            [self.manager requestWhenInUseAuthorization];
            //            [self.manager requestAlwaysAuthorization];
            
        }
    }
    
    
    self.mapView.delegate = self;
    
    /*
     
     MKMapTypeStandard = 0,//标准地图2D
     MKMapTypeSatellite, //卫星地图
     MKMapTypeHybrid, //混合地图
     
     */
    
    //设置地图类型
    self.mapView.mapType = MKMapTypeStandard;
    
    //显示用户位置
    self.mapView.showsUserLocation = YES;
    
    
}

//当用户位置改变时，调用。
- (void)mapView:(MKMapView *)mapView didUpdateUserLocation:(MKUserLocation *)userLocation {
    
    //获取当前用户的经纬度
     CLLocationCoordinate2D coordinate = userLocation.location.coordinate;
    
    //将当前屏幕设为中心点
//    [mapView setCenterCoordinate:coordinate animated:YES];
    
    /*
     
     typedef struct {
     CLLocationDegrees latitudeDelta; 纬度跨度
     CLLocationDegrees longitudeDelta; 经度跨度
     } MKCoordinateSpan;
     
     typedef struct {
     CLLocationCoordinate2D center;  中心
     MKCoordinateSpan span;
     } MKCoordinateRegion;

     
     */
    
    //设置屏幕显示区域的经纬跨度
    MKCoordinateSpan span = MKCoordinateSpanMake(0.1, 0.1);
    
    MKCoordinateRegion region = MKCoordinateRegionMake(coordinate, span);
    
    //定位可见区域
    [mapView setRegion:region animated:YES];
}