使用iOS中的Geocoder类,根据地址获取纬度和经度

Question

我根据经度和纬度值获得了当前位置,然后我还使用Annotation在Google地图上获得了多个位置.现在我想根据地址(即街道,城市和县)获取经度和纬度值.需要一些指导如何实现.

直到现在,这是我尝试过的: -

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController
@synthesize streetField = _streetField, cityField = _cityField, countryField = _countryField, fetchCoordinatesButton = _fetchCoordinatesButton, nameLabel = _nameLabel, coordinatesLabel = _coordinatesLabel;
@synthesize geocoder = _geocoder;


- (void)viewDidLoad
{

    [super viewDidLoad];
    _streetField.delegate=self;
    _cityField.delegate=self;
    _countryField.delegate=self;

    // Do any additional setup after loading the view, typically from a nib.
}

- (IBAction)fetchCoordinates:(id)sender {
    NSLog(@"Fetch Coordinates");
    if (!self.geocoder) {
          NSLog(@"Geocdoing");
        self.geocoder = [[CLGeocoder alloc] init];
    }

    NSString *address = [NSString stringWithFormat:@"%@ %@ %@", self.streetField.text, self.cityField.text, self.countryField.text];
    NSLog(@"GET Addres%@",address);

    self.fetchCoordinatesButton.enabled = NO;

    [self.geocoder geocodeAddressString:address completionHandler:^(NSArray *placemarks, NSError *error) {
          NSLog(@"Fetch Gecodingaddress");
        if ([placemarks count] > 0) {
            CLPlacemark *placemark = [placemarks objectAtIndex:0];

             NSLog(@"GET placemark%@",placemark);

            CLLocation *location = placemark.location;

            NSLog(@"GET location%@",location);

            CLLocationCoordinate2D coordinate = location.coordinate;


            self.coordinatesLabel.text = [NSString stringWithFormat:@"%f, %f", coordinate.latitude, coordinate.longitude];

            NSLog(@"CoordinatesLabel%@",self.coordinatesLabel.text);


            if ([placemark.areasOfInterest count] > 0) {
                NSString *areaOfInterest = [placemark.areasOfInterest objectAtIndex:0];
                self.nameLabel.text = areaOfInterest;
                NSLog(@"NameLabe%@",self.nameLabel.text);
            }
        }

        self.fetchCoordinatesButton.enabled = YES;
    }];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}
-(BOOL)textFieldShouldReturn:(UITextField *)textField
{
    [textField resignFirstResponder];
    return YES;
}
@end

上面的代码不能给我经纬度.需要帮助我在这里做错了什么,或者我是否缺少某些东西.

提前致谢.

Answer 1

编辑:

在使用iOS8更新的此检查之前

NSLocationAlwaysUsageDescription
NSLocationWhenInUseUsageDescription

这是为了获得基于纬度和长度的用户区域,如街道名称,州名,国家.

-(CLLocationCoordinate2D) getLocationFromAddressString: (NSString*) addressStr {
    double latitude = 0, longitude = 0;
    NSString *esc_addr =  [addressStr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
    NSString *req = [NSString stringWithFormat:@"http://maps.google.com/maps/api/geocode/json?sensor=false&address=%@", esc_addr];
    NSString *result = [NSString stringWithContentsOfURL:[NSURL URLWithString:req] encoding:NSUTF8StringEncoding error:NULL];
    if (result) {
        NSScanner *scanner = [NSScanner scannerWithString:result];
        if ([scanner scanUpToString:@"\"lat\" :" intoString:nil] && [scanner scanString:@"\"lat\" :" intoString:nil]) {
            [scanner scanDouble:&latitude];
            if ([scanner scanUpToString:@"\"lng\" :" intoString:nil] && [scanner scanString:@"\"lng\" :" intoString:nil]) {
                [scanner scanDouble:&longitude];
            }
        }
    }
    CLLocationCoordinate2D center;
    center.latitude=latitude;
    center.longitude = longitude;
    NSLog(@"View Controller get Location Logitute : %f",center.latitude);
    NSLog(@"View Controller get Location Latitute : %f",center.longitude);
    return center;

}

根据你的项目在viewdidload方法或某个地方调用这样的方法

[self getLocationFromAddressString:@"chennai"];

只需在浏览器中传递此内容 http://maps.google.com/maps/api/geocode/json?sensor=false&address=chennai

你将拥有lat和lon的json格式

http://maps.google.com/maps/api/geocode/json?sensor=false&address=@"your city name here"




 NSString *address = [NSString stringWithFormat:@"http://maps.google.com/maps/api/geocode/json?sensor=false&address=%@ %@ %@", self.streetField.text, self.cityField.text, self.countryField.text];

使用这种方法....

CLLocationCoordinate2D center;
        center=[self getLocationFromAddressString:@"uthangarai"];
      double  latFrom=&center.latitude;
      double  lonFrom=&center.longitude;

  NSLog(@"View Controller get Location Logitute : %f",latFrom);
        NSLog(@"View Controller get Location Latitute : %f",lonFrom);

Answer 2

有人在寻找Swift 2.0解决方案,可以在下面使用:

let address = "1 Infinite Loop, CA, USA"
        let geocoder = CLGeocoder()

        geocoder.geocodeAddressString(address, completionHandler: {(placemarks, error) -> Void in
            if((error) != nil){
                print("Error", error)
            }
            if let placemark = placemarks?.first {
                let coordinates:CLLocationCoordinate2D = placemark.location!.coordinate
                coordinates.latitude
                coordinates.longitude
                print("lat", coordinates.latitude)
                print("long", coordinates.longitude)


            }
        })