DidUpdateLocation not storing location, userLoc always nil - swift

I am trying to simply get the user's current device location and store it in a global variable called userLoc. I have this code to call didUpdateLocation:
self.locationManager.requestLocation()
print("aaa ", self.userLoc)
and this to set the userLoc to the current location:
func locationManager(_ manager: CLLocationManager,
didUpdateLocations locations: [CLLocation]) {
if let location = locations.last {
self.userLoc = location
}
}
userLoc is defined like this:
var userLoc: CLLocation?
but when I run the app and try to print userLoc, it ALWAYS prints:
aaa nil
The Privacy - Location When In Use Usage Description is set in the Info.plist. I honestly dont know what else to try. I've been banging my head against the wall for a while trying to fix this. Any help you could give would be very much appreciate. Thank you.

This is what I do to get user location within my view controller class. I think you are missing locationManager.startUpdatingLocation():
var currentLocation: CLLocationCoordinate2D!
var locationManager: CLLocationManager = CLLocationManager()
locationManager.delegate = self
locationManager.desiredAccuracy = kCLLocationAccuracyBest
locationManager.startUpdatingLocation()
currentLocation = locationManager.location!.coordinate

Related

Coordinates not printing when the simulator is run, but they are when I run the program on my iPhone

I have the following code
class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate, CLLocationManagerDelegate {
var locationManager = CLLocationManager()
var coordinates: String?
override func viewDidLoad() {
super.viewDidLoad()
self.locationManager.requestAlwaysAuthorization()
if CLLocationManager.locationServicesEnabled() {
locationManager.delegate = self
locationManager.desiredAccuracy = kCLLocationAccuracyBest
locationManager.startUpdatingLocation()
}
}
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
//updates the user's location as the user moves
let location: CLLocation = locations[0] as CLLocation
coordinates = "\(location.coordinate.latitude),\(location.coordinate.longitude)"
print(coordinates!)
}
When I run this on the simulator, the program works fine but it doesn't print the coordinates. When I run it on my iPhone, it prints the coordinates. Is there something in the Xcode settings I need to change to fix this? Also, when I try to use the "coordinates" variable in another function, I get an error saying the compiler is finding nil even though I assigned it a value in the locationManager function, so I'm guessing the two problems are connected. Thanks in advance
You can simulate location on the simulator using "Simulate location" button when running your app:
You can select one of the existing locations or you can create a GPX file (for example not a static single point but a route that will simulate constant changing of location). I would recommend you using https://mapstogpx.com/ to create GPX files.

Userlocation keeps updating and won´t let me move freely through my map

Let me explain myself. I have created a Map where I show some locations (pins) and the user location. When I run the App, it opens and zooms in (span), then I want to move through the map, but the App "drags" the view back to the user location (it even zooms in back to normal state). My question is, how can I stop my App from doing that over and over again? because it is kind of annoying. Thanks in advance.
The function I used for this Span process was the following...
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
let location = locations[0]
let span: MKCoordinateSpan = MKCoordinateSpanMake(1.0, 1.0)
let ubicacionUsuario: CLLocationCoordinate2D = CLLocationCoordinate2DMake(location.coordinate.latitude, location.coordinate.longitude)
let region: MKCoordinateRegion = MKCoordinateRegionMake(ubicacionUsuario, span)
mapView.setRegion(region, animated: true)
self.mapView.showsUserLocation = true
}
Inside of your didUpdateLocations function, you can create a counter. Essentially, what the counter would do is update and refresh the user's location on the map for a specific number of iterations. After that, you can use the .stopUpdatingLocation method of the CLLocationManager. So, for your case, you would have something like below:
class ViewController: UIViewController, CLLocationManagerDelegate, MKMapViewDelegate {
// Top level class stuff, create CLLocationManager Instance
var manager = CLLocationManager()
// set initial value of counter to 0
var updateCount = 0
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
//If the location has updated less than 3 times, continue to update the location
if updateCount < 3 {
let region: MKCoordinateRegion = MKCoordinateRegionMake(ubicacionUsuario, span)
mapView.setRegion(region, animated: true)
updateCount += 1
} else {
// Once the update has occurred a satisfactory number of times, prevent the update from automaitcally occuring again
manager.stopUpdatingLocation()
}
}
}

CLLocationManager is slow getting location, Swift

Im creating this app, and it needs to get the users location - its all working properly, the thing is, that the time from accepting the use of location services, to getting the actual location takes like 5 seconds - is this normal?
I've used other apps, where it goes much faster..
Here's what my code looks like:
override func viewDidLoad() {
super.viewDidLoad()
// Ask for Location-Authorisation from the User.
self.locationManager.requestWhenInUseAuthorization()
if CLLocationManager.locationServicesEnabled() {
locationManager.delegate = self
locationManager.requestLocation()
}
mapView.delegate = self
}
func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
let locValue: CLLocationCoordinate2D = manager.location!.coordinate
let initialLocation = CLLocation(latitude: locValue.latitude, longitude: locValue.longitude)
self.centerMapOnLocation(initialLocation)
}
func locationManager(manager: CLLocationManager, didFailWithError error: NSError) {
print("could not get location")
}
But the time from the application gets the location to put into the centerMapOnLocation-function, seems just to be quite long. What is to be expected, when getting a users location? I'm testing on a wifi connection, so I know its not because the internet is slow, or its a bad connection...
Anyone have an idea? :)
Best regards!
Try setting the accuracy and use locationManager.startUpdatingLocation(). I do that, and get answer within a second (on the device).
From the documentation of requestLocation():
This method returns immediately. Calling it causes the location manager to obtain a location fix (which may take several seconds) and call the delegate’s locationManager(_:didUpdateLocations:) method with the result.
Source
So basically, everything is fine with your code, it's just how the framework is built.
When initializing your location manager, add startUpdatingLocation():
let manager = CLLocationManager()
manager.delegate = self
manager.requestWhenInUseAuthorization()
manager.requestLocation()
manager.startUpdatingLocation()
Without startUpdatingLocation() geo-location takes about 5 seconds, with it, the request executes nearly immediately.
If you don't want to delay the app's launch for the location manager, consider deploying two location managers (in the app delegate), tasking one with generating a location quickly and the other with generating a location accurately:
fastLoc.delegate = self
fastLoc.desiredAccuracy = kCLLocationAccuracyThreeKilometers
fastLoc.requestWhenInUseAuthorization()
fastLoc.startUpdatingLocation()
bestLoc.delegate = self
bestLoc.desiredAccuracy = kCLLocationAccuracyBest
bestLoc.requestWhenInUseAuthorization()
bestLoc.requestLocation()
The combination of 3 km accuracy with startUpdatingLocation() should return a location almost instantly, almost always before the root view controller is even ready to go. bestLoc manager is likely to return a location well after the user has launched the app but it will be very accurate.
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
switch manager {
case fastLoc:
fastLoc.stopUpdatingLocation()
deviceLocation = locations.last! // set property with fast loc
case bestLoc:
deviceLocation = locations.last! // overwrite property with best loc
default:
break
}
}

Trouble getting one-time user location in Swift

I am trying to get the user's location at the time of a button press, however I am having trouble setting up the location code. I've been looking between various answers on Stackoverflow but I can't get anything to work for me.
class MyViewController: UIViewController, CLLocationManagerDelegate {
var locationManager = CLLocationManager()
override func viewDidLoad() {
super.viewDidLoad()
locationManager.delegate = self
locationManager.desiredAccuracy = kCLLocationAccuracyHundredMeters
locationManager.requestWhenInUseAuthorization()
locationManager.startUpdatingLocation()
}
func locationManager(manager: CLLocationManager, didChangeAuthorizationStatus status: CLAuthorizationStatus) {
if status == .AuthorizedAlways || status == .AuthorizedWhenInUse {
let latitude = self.locationManager.location?.coordinate.latitude
let longitude = self.locationManager.location?.coordinate.longitude
print("coordinates:")
print(latitude)
print(longitude)
}
}
func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
let locationValue : CLLocationCoordinate2D = manager.location!.coordinate
print("locations = \(locationValue.latitude) \(locationValue.longitude)")
}
However I just get nils from the prints in didChangeAuthorizationStatus and nothing ever prints from didUpdateLocations. Im also really confused about where to put startUpdatingLocation(). Some answers place it directly in viewDidLoad as I have here, others place it in didChangeAuthorizationStatus, and I saw another place it inside an if CLLocationManager.locationServicesEnabled() in didLoad. What is the correct way to do this? And also what have I done wrong that I'm not getting any values printing? I'm running on the emulator, have location turned on and allowed permissions in the pop-up, and have the emulator set to a lat/long custom location, and I have added the values in pList.
edit: even tried copy/pasting the code from this to get user's location only once but it returns (kCLErrorDomain error 0.). I added a 'requestWhenInUseAuthorization()` to their code but it still fails.
get nils from the prints in didChangeAuthorizationStatus
Because we don't have any locations yet. That's the wrong place to ask for that information. All that happened is that we are now authorized.
nothing ever prints from didUpdateLocations
Because you're running on the simulator, perhaps. Try running on a device.
And, if your goal is just to get the location and stop, don't use startUpdatingLocation; call requestLocation. That's what it's for.

swift - How to delay method call until variables value is stored regarding updating current location

I would like to call a method but it requires coordinates that have not been stored in variables yet.
So far I have:
1) acquired current location
2) Think I store them?
What I want to do:
1) Call method After these variables are stored so the program can run
class ViewController: UIViewController, CLLocationManagerDelegate {
let locationManager = CLLocationManager()
var clLatitude : CLLocationDegrees!
var clLongitude: CLLocationDegrees!
override func viewDidLoad() {
super.viewDidLoad()
self.locationManager.requestAlwaysAuthorization()
self.locationManager.requestWhenInUseAuthorization()
if CLLocationManager.locationServicesEnabled() {
locationManager.delegate = self
locationManager.desiredAccuracy = kCLLocationAccuracyBest
locationManager.startUpdatingLocation()
}
func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
let location:CLLocationCoordinate2D = manager.location!.coordinate
//Test printing coordinates to screen
print("locations = \(location.self.clLatitude) \(location.self.clLongitude)")
//place where I think I store the variables?
self.clLatitude = location.latitude
self.clLongitude = location.longitude
}
func methodToBeCalled(){
//to be called after variables are stored.
}
I believe I have covered everything regarding my problem
i think you just need to call the method at the end of locationManager(manager: didUpdateLocations:)
func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
let location:CLLocationCoordinate2D = manager.location!.coordinate
//Test printing coordinates to screen
print("locations = \(location.self.clLatitude) \(location.self.clLongitude)")
//place where I think I store the variables?
self.clLatitude = location.latitude
self.clLongitude = location.longitude
// call method
methodToBeCalled()
}
func methodToBeCalled(){
//to be called after variables are stored.
}