Reverse geocoding in Swift 4

Question

I\'m attempting to write a simple method that\'s fed CLLocationDegrees and returns a CLPlacemark. Looking at Apple\'s documentation, it seems like

Answer 1

There are so many questions dealing with 'reverseGeocodeLocation' on Stack Overflow, I've seen so many of them. I'm using Swift 4.2 and I thought my 'reverseGeocodeLocation' requests might be timing out. Well, this is NOT the case, when starting to move with an iPhone the 'didUpdateLocations' cycles need to mature. It can take two or more cycles before 'reverseGeocodeLocation' returns placemarks.

I wrote a simple app that uses 'reverseGeocodeLocation' until 'placemarks' are returned after repeated 'didUpdateLocations' cycles. This is my own home grown 'SampleCode'. I learned a lot from using the app, it might help others understand how reverse geocode requests work in the real world.

Please give your comments on possible improvements. This code is freely given and freely taken.

import Foundation
import UIKit
import CoreLocation

class ViewController: UIViewController, CLLocationManagerDelegate {
    @IBAction func RefreshLocationButton(_ sender: Any) {
        self.requestingPlacemark = true
        self.placemarkData = nil
        //^Make another Placemark Request
        self.requestCounter = 0
        self.RequestCounterLabel.text = ""
        self.LocationLabel.text = ""
        self.PlacemarkLabel.text = ""}
    @IBOutlet weak var LocationCounterLabel: UILabel!
    @IBOutlet weak var RequestCounterLabel: UILabel!
    @IBOutlet weak var LocationLabel: UILabel!
    @IBOutlet weak var PlacemarkLabel: UILabel!
    let locationManager = CLLocationManager()
    var placemarkData: CLPlacemark!
    var placemarkString: String!
    var printPlacemarkData: Bool!
    var didUpdateLocationsCounter: Int = 0
    var requestCounter: Int = 0
    var requestingPlacemark: Bool = true

override func viewDidLoad() {
    super.viewDidLoad()
    if CLLocationManager.locationServicesEnabled() {
        locationManager.requestAlwaysAuthorization()
        locationManager.delegate = self
        //locationManager.desiredAccuracy = kCLLocationAccuracyBest
        locationManager.desiredAccuracy = kCLLocationAccuracyBestForNavigation
        locationManager.startUpdatingLocation()
        self.RequestCounterLabel.text = ""
        self.LocationLabel.text = ""
        self.PlacemarkLabel.text = ""}}
func printPlacemarks() {
    if printPlacemarkData {
        self.placemarkString = "Placemark Data:"
        self.placemarkString = buildPlacemarkString(item: 1)
        self.placemarkString = buildPlacemarkString(item: 2)
        self.placemarkString = buildPlacemarkString(item: 3)
        self.placemarkString = buildPlacemarkString(item: 4)
        self.placemarkString = buildPlacemarkString(item: 5)
        self.placemarkString = buildPlacemarkString(item: 6)
        self.placemarkString = buildPlacemarkString(item: 7)
        self.placemarkString = buildPlacemarkString(item: 8)
        self.placemarkString = buildPlacemarkString(item: 9)
        self.placemarkString = buildPlacemarkString(item: 10)
        self.PlacemarkLabel.text = self.placemarkString
        self.printPlacemarkData = false}}
func buildPlacemarkString(item: Int) -> String {
    var elementText: String!
    var newString: String!
        switch item {
        case 1: elementText = "name: " + self.placemarkData.name!
        case 2: elementText = "subThoroughfare: " + self.placemarkData.subThoroughfare!
        case 3: elementText = "thoroughfare: " + self.placemarkData.thoroughfare!
        case 4: elementText = "postalCode: " + self.placemarkData.postalCode!
        case 5: elementText = "subLocality: " + self.placemarkData.subLocality!
        case 6: elementText = "locality: " + self.placemarkData.locality!
        case 7: elementText = "subAdministrativeArea: " + self.placemarkData.subAdministrativeArea!
        case 8: elementText = "administrativeArea: " + self.placemarkData.administrativeArea!
        case 9: elementText = "country: " + self.placemarkData.country!
        case 10: elementText = "isoCountryCode: " + self.placemarkData.isoCountryCode!
        default: print("Error: incorrect item number!")}
        newString = self.placemarkString + "\n" + elementText
    return newString
}
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        //location prints one time and 'didUpdateLocations' is stopped:
    self.didUpdateLocationsCounter = self.didUpdateLocationsCounter + 1
    let labelString = String(describing: self.didUpdateLocationsCounter)
    self.LocationCounterLabel.text = "Location Update Counter: " + labelString
    if self.placemarkData == nil {
        //location variable:
        self.requestCounter = self.requestCounter + 1
        let textString = String(describing: self.requestCounter)
        self.RequestCounterLabel.text = "Request Counter: " + textString
        if locations.count == 0 {
            self.LocationLabel.text = "Locations: There was NONE"}
        else {
            if locations.count > 0 {
                let coordinate2D: CLLocation = locations.first!
                let location = CLLocation(latitude: coordinate2D.coordinate.latitude, longitude: coordinate2D.coordinate.longitude)
                let printString = String(describing: location)
                self.LocationLabel.text = "Location: " + printString
                let geocoder: CLGeocoder = CLGeocoder()
                geocoder.reverseGeocodeLocation(location, completionHandler: {(placemarks, error) -> Void in
                    if error != nil {
                        let errorString = String(describing: error?.localizedDescription)
                        print("reverse geodcode fail: \(errorString)")
                        self.LocationCounterLabel.text = ""
                        self.RequestCounterLabel.text = ""
                        self.LocationLabel.text = "Reverse Geodcode fail: \(errorString)"
                        self.PlacemarkLabel.text = ""
                        self.requestingPlacemark = false
                        return}
                    else {
                        let pm = placemarks! as [CLPlacemark]
                        //There is ALWAYS 'placemarks' Data
                        if pm.count > 0 {
                            self.placemarkData = placemarks![0]
                            self.printPlacemarkData = true
                            self.printPlacemarks()
                            self.requestingPlacemark = false}}})}
            else {
                if self.requestingPlacemark {
                    self.LocationLabel.text = "Problem: There is no 'location.first'"}}}}}}

And then the Storyboard UI:

Storyboard Image

View Controller Image