最新的 iOS 版本 (12.4) 不推荐使用 didUpdateLocationsTo: from: 方法。如何用 didUpdateLocations 替换它？

Question

我正在尝试在我的示例应用中实现经度和纬度。我使用 iPhone 5s 设备进行测试。它不会对按钮操作上的纬度和经度标签产生任何影响。

在编译 Xcode 之前在 didUpdateToLocation: fromLocation: method as 行显示警告

“实现不推荐使用的方法”

请帮助我用合适的方法代替此方法以使应用程序顺利运行

使用 Xcode 12.4 和 iOS 12.3 使用 Objective c 我正在尝试实现一个显示经度和纬度的简单位置演示应用程序。下面是我的 viewController.h 和 viewController.m 文件。我已经尝试了以下来自在线教程AppCoda的代码

viewController.h

#import <UIKit/UIKit.h>
#import <CoreLocation/CoreLocation.h>
@interface ViewController :UIViewController<CLLocationManagerDelegate>
{
  IBOutlet UILabel *lattitudeLabel;
  IBOutlet UILabel *longitudeLabel;
  IBOutlet UILabel *addressLabel;
}
- (IBAction)getCurrentLocation:(UIButton *)sender;
@end

viewController.m

#import "ViewController.h"

@interface ViewController ()
{
  CLLocationManager *locationManager;
  CLGeocoder *geocoder;
  CLPlacemark *placemark;
}

@end

@implementation ViewController

- (void)viewDidLoad {
[super viewDidLoad];
  locationManager = [[CLLocationManager alloc]init];
  geocoder = [[CLGeocoder alloc] init];
}


- (IBAction)getCurrentLocation:(UIButton *)sender
{
  locationManager.delegate = self;
  locationManager.desiredAccuracy = kCLLocationAccuracyBest;
  [locationManager startUpdatingLocation];
}
#pragma mark - CLLocationManagerDelegate

- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error
{
NSLog(@"didFailWithError: %@", error);
  NSLog(@"Error: Failed to get location");
}

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
NSLog(@"didUpdateToLocation: %@", newLocation);
CLLocation *currentLocation = newLocation;

if (currentLocation != nil) {
longitudeLabel.text = [NSString stringWithFormat:@"%.8f", currentLocation.coordinate.longitude];
lattitudeLabel.text = [NSString stringWithFormat:@"%.8f", currentLocation.coordinate.latitude];
}
  
  [locationManager stopUpdatingLocation];
  
  NSLog(@"Resolving the Address");
  [geocoder reverseGeocodeLocation:currentLocation completionHandler:^(NSArray *placemarks, NSError *error) {
      NSLog(@"Found placemarks: %@, error: %@", placemarks, error);
      if (error == nil && [placemarks count] > 0) {
        self->placemark = [placemarks lastObject];
        self->addressLabel.text = [NSString stringWithFormat:@"%@ %@\n%@ %@\n%@\n%@",
                       self->placemark.subThoroughfare, self->placemark.thoroughfare,
                       self->placemark.postalCode, self->placemark.locality,
                       self->placemark.administrativeArea,
                       self->placemark.country];
      } else {
      NSLog(@"%@", error.debugDescription);
      }
  } ];
}
@end

点击按钮获取我的位置没有发生任何事情。它实际上应该更新除经度之外的坐标：和纬度：一些浮点值..但它没有这样做..我会问请建议我链接到任何教程网站或任何 GitHub 项目的链接，以便在 iOS 12.3 和以上目标c...感谢您的回复和建议的编辑。

Answer 1

正如docs 所说，只需使用locationManager(_:didUpdateLocations:) 。

斯威夫特 5

func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    // Stop updates if this is a one-time request
    manager.stopUpdatingLocation()
    
    // Pop the last location off if you just need current update
    guard let newLocation = locations.last else { return }
    
    <... Do something with the location ...>
}

Objective-C

- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray<CLLocation *> *)locations {
    [manager stopUpdatingLocation];

    CLLocation *newLocation = [locations lastObject];
    if (newLocation) {
        <... Do something with the location ...>
    }
}

Answer 2

我希望这个委托方法的实现对你有所帮助。 适用于 Mac 和 IOS。我用它来确定天气应用程序的当前位置。

- (void)locationManager:(CLLocationManager *)manager
     didUpdateLocations:(NSArray<CLLocation *> *)locations
{
    if (locations.count > 0) {
        // Location manager has nonempty array of readings
        // We take the las one - the latest position determined
        CLLocation *last = locations[locations.count - 1];
        // Evaluate threshold distance to notice change
        CLLocationDistance distance = LOCATOR_SENSITIVITY + 1;
        if (previous) {
             // calculate distance from previous location
             distance = [last distanceFromLocation:previous];
        }
        // update previous location
        previous = last;
        if (distance > LOCATOR_SENSITIVITY) {
            // If we moved far enough, update current position
            currentLat = last.coordinate.latitude;
            currentLon = last.coordinate.longitude;
            // and notify all observers 
            // You can use delegate here, dispatch_async wrapper etc.
            [[NSNotificationCenter defaultCenter] 
                 postNotificationName:LocationIsChanged object:nil];
        }
    }
}