iOS:CoreLocation实现定位当前城市

首先导入头文件

#import <CoreLocation/CoreLocation.h>

在info.plist文件中添加:

注:NSLocationAlwaysUsageDescription可以不添加

下面是具体用法的demo:

注意:
1.[CLLocationManager locationServicesEnabled]判断定位是否开启是判断的整个手机系统的定位是否打开,并不是针对这一应用.
2.具体在本应用中的是否已经授权定位要通过代理方法判断
如果定位失败(未授权)则会执行此代理方法

- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error {

}

具体代码:

@interface ViewController ()<CLLocationManagerDelegate>
{
    CLLocationManager * locationManager;
    NSString * currentCity; //当前城市
}
@end
@implementation ViewController
- (void)viewDidLoad {
    [super viewDidLoad];
    [self locate]; 
}

- (void)locate { 
     //判断定位功能是否打开
    if ([CLLocationManager locationServicesEnabled]) {
        locationManager = [[CLLocationManager alloc] init];
        locationManager.delegate = self;
//        [locationManager requestAlwaysAuthorization];
        currentCity = [[NSString alloc] init];
        [locationManager startUpdatingLocation];    
    }
    
}

#pragma mark CoreLocation delegate  

//定位失败则执行此代理方法
//定位失败弹出提示框,点击"打开定位"按钮,会打开系统的设置,提示打开定位服务
- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error {
    UIAlertController * alertVC = [UIAlertController alertControllerWithTitle:@"允许\"定位\"提示" message:@"请在设置中打开定位" preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction * ok = [UIAlertAction actionWithTitle:@"打开定位" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
        //打开定位设置
        NSURL *settingsURL = [NSURL URLWithString:UIApplicationOpenSettingsURLString];
        [[UIApplication sharedApplication] openURL:settingsURL];
    }];
    UIAlertAction * cancel = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
        
    }];
    [alertVC addAction:cancel];
    [alertVC addAction:ok];
    [self presentViewController:alertVC animated:YES completion:nil];
    
}
//定位成功
- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray<CLLocation *> *)locations {
    [locationManager stopUpdatingLocation];
    CLLocation *currentLocation = [locations lastObject];
    CLGeocoder * geoCoder = [[CLGeocoder alloc] init];
    
      //反编码
    [geoCoder reverseGeocodeLocation:currentLocation completionHandler:^(NSArray<CLPlacemark *> * _Nullable placemarks, NSError * _Nullable error) {     
        if (placemarks.count > 0) {
            CLPlacemark *placeMark = placemarks[0];
            currentCity = placeMark.locality;  
            if (!currentCity) {
                currentCity = @"无法定位当前城市";
            } 
            NSLog(@"%@",currentCity); //这就是当前的城市
            NSLog(@"%@",placeMark.name);//具体地址:  xx市xx区xx街道
        }
        else if (error == nil && placemarks.count == 0) {
            NSLog(@"No location and error return");
        }
        else if (error) {
            NSLog(@"location error: %@ ",error);
        }
  
    }];     
}
@end