访问 iPhone 的当前位置

Posted 2023-03-05

【中文标题】访问 iPhone 的当前位置

【英文标题】：Accessing iPhone's current location

【发布时间】：2010-10-23 22:26:22

【问题描述】：

如何将 iPhone 当前位置的经纬度坐标存储到两个不同的浮点变量中？

【参考方案1】：

This 教程将帮助您做到这一点。

这是您可能感兴趣的教程中的相关代码：

- (void)locationManager:(CLLocationManager *)manager
    didUpdateToLocation:(CLLocation *)newLocation
           fromLocation:(CLLocation *)oldLocation

  int degrees = newLocation.coordinate.latitude;
  double decimal = fabs(newLocation.coordinate.latitude - degrees);
  int minutes = decimal * 60;
  double seconds = decimal * 3600 - minutes * 60;
  NSString *lat = [NSString stringWithFormat:@"%d° %d' %1.4f\"", 
                   degrees, minutes, seconds];
  latLabel.text = lat;
  degrees = newLocation.coordinate.longitude;
  decimal = fabs(newLocation.coordinate.longitude - degrees);
  minutes = decimal * 60;
  seconds = decimal * 3600 - minutes * 60;
  NSString *longt = [NSString stringWithFormat:@"%d° %d' %1.4f\"", 
                     degrees, minutes, seconds];
  longLabel.text = longt;

【参考方案2】：

Chetan 的答案非常好，可以为您提供经度和经度的度数。万一您只对以单位存储纬度和经度感兴趣，然后您可以使用这些单位与其他位置进行比较，您可以执行以下操作：

- (void)locationManager:(CLLocationManager *)manager
didUpdateToLocation:(CLLocation *)newLocation
       fromLocation:(CLLocation *)oldLocation 
CLLocationDegrees latitude = newLocation.coordinate.latitude;
CLLocationDegrees longitude = newLocation.coordinate.longitude;
...

如果您想保留这些，那么您需要为这些值提供某种存储。否则，它们将在方法结束时超出范围。

请注意，CLLocationDegrees 只是一个具有漂亮名称的双精度数。

请记住，CLLocation.coordinate 是一个简洁的结构，您可以将其存储为 CLLocationCoordinate2D - 将这些值保持在一起会更加优雅，因为它们保留了更多上下文。

【参考方案3】：

你可以初始化一个 CLLocationManager 来找到一个点并在后面引用它（注意这个初始化是从另一篇文章中借来的）。

CLLocationManager *curLocationManager = [[CLLocationManager alloc] init];
curLocationManager.delegate        = self;  //SET YOUR DELEGATE HERE
curLocationManager.desiredAccuracy = kCLLocationAccuracyBest; //SET THIS TO SPECIFY THE ACCURACY
[curLocationManager startUpdatingLocation];

//NSLog(@"currentLocationManager is %@", [curLocationManager.location description]);
[curLocationManager stopUpdatingLocation];
//NSLog(@"currentLocationManager is now %@", [curLocationManager.location description]);
//NSLog(@"latitude %f", curLocationManager.location.coordinate.latitude);
//NSLog(@"longitude %f", curLocationManager.location.coordinate.longitude);

double latitude = curLocationManager.location.coordinate.latitude;
double longitude = curLocationManager.location.coordinate.longitude;

请注意，您还需要包含(CLLocationManager *)locationManager 和(void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation，并且您应该包含(void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error

【参考方案4】：

使用以下代码在 MKMapView 中显示当前位置并在 iPhone 应用程序中设置缩放级别。

1) 在您的项目中添加 MApKit 和 CoreLocation 框架。

2) 在 ViewController.h 文件中使用以下代码：

#import "mapKit/MapKit.h"
#import "CoreLocation/CoreLocation.h"

@interface ViewController : UIViewController<MKMapViewDelegate, CLLocationManagerDelegate>

      MKMapView *theMapView;
      CLLocationManager *locationManager;
      CLLocation *location;
      float latitude, longitude;

3) 在 vi​​ewDidLoad 方法中添加如下代码：

   // Add MKMapView in your View 

   theMapView=[[MKMapView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
   theMapView.delegate=self;
   [self.view addSubview:theMapView];

   // Create an instance of CLLocationManager

   locationManager=[[CLLocationManager alloc] init];
   locationManager.desiredAccuracy=kCLLocationAccuracyBest;
   locationManager.delegate=self;
   [locationManager startUpdatingLocation];

   // Create an instance of CLLocation

   location=[locationManager location];

   // Set Center Coordinates of MapView

   theMapView.centerCoordinate=CLLocationCoordinate2DMake(location.coordinate.latitude, location.coordinate.longitude);

   // Set Annotation to show current Location 

   MKPointAnnotation *annotaionPoint=[[MKPointAnnotation alloc] init];
   annotaionPoint.coordinate=theMapView.centerCoordinate;
   annotaionPoint.title=@"New Delhi";
   annotaionPoint.subtitle=@"Capital";
   [theMapView addAnnotation:annotaionPoint];

   // Setting Zoom Level on MapView

   MKCoordinateRegion coordinateRegion;   

   coordinateRegion.center = theMapView.centerCoordinate;
   coordinateRegion.span.latitudeDelta = 1;
   coordinateRegion.span.longitudeDelta = 1;

   [theMapView setRegion:coordinateRegion animated:YES];

    // Show userLocation (Blue Circle)

   theMapView.showsUserLocation=YES;

4) 使用以下位置更新用户位置

   -(void)mapView:(MKMapView *)mapView didUpdateUserLocation:(MKUserLocation *)userLocation
    
         latitude=userLocation.coordinate.latitude;
         longitude=userLocation.coordinate.longitude;

         theMapView.centerCoordinate=CLLocationCoordinate2DMake(latitude, longitude);

         MKPointAnnotation *annotationPoint=[[MKPointAnnotation alloc] init];
         annotationPoint.coordinate=theMapView.centerCoordinate;
         annotationPoint.title=@"Moradabad";
         annotationPoint.subtitle=@"My Home Town";