Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
415 views
in Technique[技术] by (71.8m points)

iphone - Get latitude and longitude based on Address using Geocoder class in iOS

I got the current location based on the Longitude and Latitude values and then I also got multiple places on google map using Annotation. Now I want to get the longitude and latitude values based on the Address( i.e street,city and county).Need some guidance on how this can be achieved.

Till now, this is what I have tried:-

#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

Above code is not working to give me the latitude and longitude.Need some help on what am I doing wrong here or if I am missing on something.

Thanks in Advance.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

This was very old answer, Kindly check with new Updates

EDIT:

Before using this check with iOS8 updation

NSLocationAlwaysUsageDescription
NSLocationWhenInUseUsageDescription

This is for getting lat and long based user area like street name,state name,country.

-(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;
    
}

call the method like this in viewdidload method or somewhere according to your project

[self getLocationFromAddressString:@"chennai"];

just pass this in your browser http://maps.google.com/maps/api/geocode/json?sensor=false&address=chennai

and you will have json format with lat and lon

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];

the usage of this method....

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);

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...