问题
How can I get the current location from user in iOS?
回答1:
The answer of RedBlueThing worked quite well for me. Here is some sample code of how I did it.
Header
#import <UIKit/UIKit.h>
#import <CoreLocation/CoreLocation.h>
@interface yourController : UIViewController <CLLocationManagerDelegate> {
CLLocationManager *locationManager;
}
@end
MainFile
In the init method
locationManager = [[CLLocationManager alloc] init];
locationManager.delegate = self;
locationManager.distanceFilter = kCLDistanceFilterNone;
locationManager.desiredAccuracy = kCLLocationAccuracyBest;
[locationManager startUpdatingLocation];
Callback function
- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation {
NSLog(@"OldLocation %f %f", oldLocation.coordinate.latitude, oldLocation.coordinate.longitude);
NSLog(@"NewLocation %f %f", newLocation.coordinate.latitude, newLocation.coordinate.longitude);
}
iOS 6
In iOS 6 the delegate function was deprecated. The new delegate is
- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
Therefore to get the new position use
[locations lastObject]
iOS 8
In iOS 8 the permission should be explicitly asked before starting to update location
locationManager = [[CLLocationManager alloc] init];
locationManager.delegate = self;
locationManager.distanceFilter = kCLDistanceFilterNone;
locationManager.desiredAccuracy = kCLLocationAccuracyBest;
if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0)
[self.locationManager requestWhenInUseAuthorization];
[locationManager startUpdatingLocation];
You also have to add a string for the NSLocationAlwaysUsageDescription or NSLocationWhenInUseUsageDescription keys to the app's Info.plist. Otherwise calls to startUpdatingLocation will be ignored and your delegate will not receive any callback.
And at the end when you are done reading location call stopUpdating location at suitable place.
[locationManager stopUpdatingLocation];
回答2:
In iOS 6, the
- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
is deprecated.
Use following code instead
- (void)locationManager:(CLLocationManager *)manager
didUpdateLocations:(NSArray *)locations {
CLLocation *location = [locations lastObject];
NSLog(@"lat%f - lon%f", location.coordinate.latitude, location.coordinate.longitude);
}
For iOS 6~8, the above method is still necessary, but you have to handle authorization.
_locationManager = [CLLocationManager new];
_locationManager.delegate = self;
_locationManager.distanceFilter = kCLDistanceFilterNone;
_locationManager.desiredAccuracy = kCLLocationAccuracyBest;
if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0 &&
[CLLocationManager authorizationStatus] != kCLAuthorizationStatusAuthorizedWhenInUse
//[CLLocationManager authorizationStatus] != kCLAuthorizationStatusAuthorizedAlways
) {
// Will open an confirm dialog to get user's approval
[_locationManager requestWhenInUseAuthorization];
//[_locationManager requestAlwaysAuthorization];
} else {
[_locationManager startUpdatingLocation]; //Will update location immediately
}
This is the delegate method which handle user's authorization
#pragma mark - CLLocationManagerDelegate
- (void)locationManager:(CLLocationManager*)manager didChangeAuthorizationStatus:(CLAuthorizationStatus)status
{
switch (status) {
case kCLAuthorizationStatusNotDetermined: {
NSLog(@"User still thinking..");
} break;
case kCLAuthorizationStatusDenied: {
NSLog(@"User hates you");
} break;
case kCLAuthorizationStatusAuthorizedWhenInUse:
case kCLAuthorizationStatusAuthorizedAlways: {
[_locationManager startUpdatingLocation]; //Will update location immediately
} break;
default:
break;
}
}
回答3:
You use the CoreLocation framework to access location information about your user. You will need to instantiate a CLLocationManager object and call the asynchronous startUpdatingLocation message. You will get callbacks with the user's location via the CLLocationManagerDelegate that you supply.
回答4:
Try this Simple Steps....
NOTE: Please check device location latitude & logitude if you are using simulator means. By defaults its none only.
Step 1: Import CoreLocation framework in .h File
#import <CoreLocation/CoreLocation.h>
Step 2: Add delegate CLLocationManagerDelegate
@interface yourViewController : UIViewController<CLLocationManagerDelegate>
{
CLLocationManager *locationManager;
CLLocation *currentLocation;
}
Step 3: Add this code in class file
- (void)viewDidLoad
{
[super viewDidLoad];
[self CurrentLocationIdentifier]; // call this method
}
Step 4: Method to detect current location
//------------ Current Location Address-----
-(void)CurrentLocationIdentifier
{
//---- For getting current gps location
locationManager = [CLLocationManager new];
locationManager.delegate = self;
locationManager.distanceFilter = kCLDistanceFilterNone;
locationManager.desiredAccuracy = kCLLocationAccuracyBest;
[locationManager startUpdatingLocation];
//------
}
Step 5: Get location using this method
- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
{
currentLocation = [locations objectAtIndex:0];
[locationManager stopUpdatingLocation];
CLGeocoder *geocoder = [[CLGeocoder alloc] init] ;
[geocoder reverseGeocodeLocation:currentLocation completionHandler:^(NSArray *placemarks, NSError *error)
{
if (!(error))
{
CLPlacemark *placemark = [placemarks objectAtIndex:0];
NSLog(@"\nCurrent Location Detected\n");
NSLog(@"placemark %@",placemark);
NSString *locatedAt = [[placemark.addressDictionary valueForKey:@"FormattedAddressLines"] componentsJoinedByString:@", "];
NSString *Address = [[NSString alloc]initWithString:locatedAt];
NSString *Area = [[NSString alloc]initWithString:placemark.locality];
NSString *Country = [[NSString alloc]initWithString:placemark.country];
NSString *CountryArea = [NSString stringWithFormat:@"%@, %@", Area,Country];
NSLog(@"%@",CountryArea);
}
else
{
NSLog(@"Geocode failed with error %@", error);
NSLog(@"\nCurrent Location Not Detected\n");
//return;
CountryArea = NULL;
}
/*---- For more results
placemark.region);
placemark.country);
placemark.locality);
placemark.name);
placemark.ocean);
placemark.postalCode);
placemark.subLocality);
placemark.location);
------*/
}];
}
回答5:
In Swift (for iOS 8+).
Info.plist
First things first. You need to add your descriptive string in the info.plist file for the keys NSLocationWhenInUseUsageDescription or NSLocationAlwaysUsageDescription depending on what kind of service you are requesting
Code
import Foundation
import CoreLocation
class LocationManager: NSObject, CLLocationManagerDelegate {
let manager: CLLocationManager
var locationManagerClosures: [((userLocation: CLLocation) -> ())] = []
override init() {
self.manager = CLLocationManager()
super.init()
self.manager.delegate = self
}
//This is the main method for getting the users location and will pass back the usersLocation when it is available
func getlocationForUser(userLocationClosure: ((userLocation: CLLocation) -> ())) {
self.locationManagerClosures.append(userLocationClosure)
//First need to check if the apple device has location services availabel. (i.e. Some iTouch's don't have this enabled)
if CLLocationManager.locationServicesEnabled() {
//Then check whether the user has granted you permission to get his location
if CLLocationManager.authorizationStatus() == .NotDetermined {
//Request permission
//Note: you can also ask for .requestWhenInUseAuthorization
manager.requestWhenInUseAuthorization()
} else if CLLocationManager.authorizationStatus() == .Restricted || CLLocationManager.authorizationStatus() == .Denied {
//... Sorry for you. You can huff and puff but you are not getting any location
} else if CLLocationManager.authorizationStatus() == .AuthorizedWhenInUse {
// This will trigger the locationManager:didUpdateLocation delegate method to get called when the next available location of the user is available
manager.startUpdatingLocation()
}
}
}
//MARK: CLLocationManager Delegate methods
@objc func locationManager(manager: CLLocationManager, didChangeAuthorizationStatus status: CLAuthorizationStatus) {
if status == .AuthorizedAlways || status == .AuthorizedWhenInUse {
manager.startUpdatingLocation()
}
}
func locationManager(manager: CLLocationManager, didUpdateToLocation newLocation: CLLocation, fromLocation oldLocation: CLLocation) {
//Because multiple methods might have called getlocationForUser: method there might me multiple methods that need the users location.
//These userLocation closures will have been stored in the locationManagerClosures array so now that we have the users location we can pass the users location into all of them and then reset the array.
let tempClosures = self.locationManagerClosures
for closure in tempClosures {
closure(userLocation: newLocation)
}
self.locationManagerClosures = []
}
}
Usage
self.locationManager = LocationManager()
self.locationManager.getlocationForUser { (userLocation: CLLocation) -> () in
print(userLocation)
}
回答6:
The Xcode Documentation has a wealth of knowledge and sample apps - check the Location Awareness Programming Guide.
The LocateMe sample project illustrates the effects of modifying the CLLocationManager's different accuracy settings
回答7:
iOS 11.x Swift 4.0 Info.plist needs these two properties
<key>NSLocationAlwaysAndWhenInUseUsageDescription</key>
<string>We're watching you</string>
<key>NSLocationWhenInUseUsageDescription</key>
<string>Watch Out</string>
And this code ... making sure of course your a CLLocationManagerDelegate
let locationManager = CLLocationManager()
// MARK location Manager delegate code + more
func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
switch status {
case .notDetermined:
print("User still thinking")
case .denied:
print("User hates you")
case .authorizedWhenInUse:
locationManager.stopUpdatingLocation()
case .authorizedAlways:
locationManager.startUpdatingLocation()
case .restricted:
print("User dislikes you")
}
And of course this code too which you can put in viewDidLoad().
locationManager.delegate = self
locationManager.requestAlwaysAuthorization()
locationManager.distanceFilter = kCLDistanceFilterNone
locationManager.desiredAccuracy = kCLLocationAccuracyBest
locationManager.requestLocation()
And these two for the requestLocation to get you going, aka save you having to get out of your seat :)
func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
print(error)
}
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
print(locations)
}
回答8:
You can use this service I wrote to handle everything for you.
This service will request the permissions and handle dealing with the CLLocationManager so you don't have to.
Use like this:
LocationService.getCurrentLocationOnSuccess({ (latitude, longitude) -> () in
//Do something with Latitude and Longitude
}, onFailure: { (error) -> () in
//See what went wrong
print(error)
})
回答9:
For Swift 5, here's a quick short class to get the location:
class MyLocationManager: NSObject, CLLocationManagerDelegate {
let manager: CLLocationManager
override init() {
manager = CLLocationManager()
super.init()
manager.delegate = self
manager.distanceFilter = kCLDistanceFilterNone
manager.desiredAccuracy = kCLLocationAccuracyBest
manager.requestWhenInUseAuthorization()
manager.startUpdatingLocation()
}
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
// do something with locations
}
}
来源：https://stackoverflow.com/questions/4152003/how-can-i-get-current-location-from-user-in-ios