Warm tip: This article is reproduced from stackoverflow.com, please click
ios swift mkmapview cllocationmanager

Show Current Location and Update Location in MKMapView in Swift

发布于 2020-03-29 21:00:48

I am learning how to use the new Swift language (only Swift, no Objective-C). To do it, I want to do a simple view with a map (MKMapView). I want to find and update the location of the user (like in the Apple Map app).

I tried this, but nothing happened:

import MapKit
import CoreLocation

class MapView : UIViewController, CLLocationManagerDelegate {

    @IBOutlet weak var map: MKMapView!
    var locationManager: CLLocationManager!

    override func viewDidLoad() {
        super.viewDidLoad()

        if (CLLocationManager.locationServicesEnabled())
        {
            locationManager = CLLocationManager()
            locationManager.delegate = self
            locationManager.desiredAccuracy = kCLLocationAccuracyBest
            locationManager.requestAlwaysAuthorization()
            locationManager.startUpdatingLocation()
        }
    }
}

Could you please help me?

Questioner
PMIW
Viewed
28
分享
3,547 2018-07-28 17:27

You have to override CLLocationManager.didUpdateLocations (part of CLLocationManagerDelegate) to get notified when the location manager retrieves the current location:

func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    if let location = locations.last{
        let center = CLLocationCoordinate2D(latitude: location.coordinate.latitude, longitude: location.coordinate.longitude)
        let region = MKCoordinateRegion(center: center, span: MKCoordinateSpan(latitudeDelta: 0.01, longitudeDelta: 0.01))
        self.map.setRegion(region, animated: true)
    }
}

NOTE: If your target is iOS 8 or above, you must include the NSLocationAlwaysUsageDescription or NSLocationWhenInUseUsageDescription key in your Info.plist to get the location services to work.

PMIW 2014-08-23 01:44:11

Thanks for your answer Zisoft. But, to use the function, I have to "save" all my new locations in a kind of list ? Then, is startUpdatingLocation() suffisant to update the location ? NOTE: Euh... sorry but how can I do it please ? :s Thank you very much !

zisoft 2014-08-23 01:55:22

After you have called startUpdatingLocation once, didUpdateLocations is fired everytime a location change is detected. You can do whatever you need with the location, i.e. store it in an array to draw a path on the map view.

PMIW 2014-08-23 03:40:38

ok thanks. And how can I include the NSLocationAlwaysUsageDescription key in my Info.plist please ?

zisoft 2014-08-23 04:22:15

In XCode, click on Info.plist and add a new row. Use NSLocationAlwaysUsageDescription as the key and the text you want to present to the user as value (String).

PMIW 2014-08-23 04:28:31

Ok Thank you ! And no value ?

Related issues

1
Want to save Core Data but "Extensions must not contain stored properties"
2
Remove a dict entry from Info.plist with plutil/PlistBuddy
3
Swift
4
Animate CALayer border change
5
Determine source code line No. from Swift Crash log
6
RealmSwift: No such module 'RealmSwift'
7
Is UIKit still using OpenGL rendering in 2020?
8
Waze doesn't load navigation from Swift
9
What does the "automatically adjusts font requires using a dynamic type text style" warning mean?
10
SwiftUI