Get API Coordinates and Show city in SwiftUI - ios

Question

I call an API and get a response with a longitude and latitude. Now, I'm trying to show and update the city name. I made a function ("place") to convert the longitude and latitude to a city name. Unfortunately is doesn't work. Please, who could give me a help on this one? Thanks in advance.
Below I will show the code. I filled the struct "APIcoord" with lat and lon example coordinates.
public final class WeatherService: NSObject {
private let locationManager = CLLocationManager()
private var completionHandler: ((Weather) -> Void)?
public override init() {
super.init()
locationManager.delegate = self
}
public func loadWeatherData(_ completionhandler: #escaping((Weather) -> Void)) {
self.completionHandler = completionhandler
locationManager.requestWhenInUseAuthorization()
locationManager.startUpdatingLocation()
}
private func makeDataRequest(forCoordinates coorodinates: CLLocationCoordinate2D) {
}
}
extension WeatherService: CLLocationManagerDelegate {
public func locationManager(
_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]
) {
guard let location = locations.first else {return}
makeDataRequest(forCoordinates: location.coordinate)
}
public func locationManager(
_ manager: CLLocationManager, didFailWithError error: Error
) {
print("Something went wrong: \(error.localizedDescription)")
}
}
struct APIResponse: Decodable {
let coord: APIcoord
}
struct APIcoord: Decodable{
let lon: Double = -122.031
let lat: Double = 37.33
}
public struct Weather {
let longtitude: Double
let latitude: Double
init(response: APIResponse) {
longtitude = response.coord.lon
latitude = response.coord.lat
}
}
public class WeaterViewModel: ObservableObject {
#Published var longtitude: Double = 0.0
#Published var latitude: Double = 0.0
public let weatherService: WeatherService
public init(weatherService: WeatherService) {
self.weatherService = weatherService
}
public func refresh() {
weatherService.loadWeatherData { weather in
DispatchQueue.main.sync {
self.longtitude = weather.longtitude
self.latitude = weather.latitude
}
}
}
}
struct ContentView: View {
#ObservedObject var viewModel: WeaterViewModel
#State var placeFound: String?
var body: some View {
NavigationView{
ZStack{
VStack {
Text(placeFound ?? "No Place Found")
.onAppear(){
place(APIlatitude: viewModel.latitude, APIlongitude: viewModel.longtitude){(city) in
placeFound = city
print("Place: \(String(describing: city))" )
}
}
}
.onAppear{
viewModel.refresh()
}
}
.navigationBarHidden(true)
}
}
func place(APIlatitude : Double, APIlongitude : Double, completion: #escaping (String?) -> Void) {
let geoCoder = CLGeocoder()
let location = CLLocation(latitude: APIlatitude, longitude: APIlongitude)
geoCoder.reverseGeocodeLocation(location, completionHandler: { (placemarks, _) -> Void in
placemarks?.forEach { (placemark) in
if let city = placemark.locality {
print(city)
completion(city)
}
else{
print("Can't find place")
}
}
})
}
}

Answer 1

You could pair GLGeocoder's async API with SwiftUI's task like this:
struct ContentView: View {
#StateObject var locator = Locator()
var body: some View {
if let location = locator.location {
ContentView2(location: location)
}
else {
Text("Hello, world!")
.padding()
}
}
}
struct ContentView2Config {
let geocoder = CLGeocoder()
var text = Self.noCityText
static let noCityText = "No City"
mutating func reverseGeocode(location: Location) async {
text = Self.noCityText
let location = CLLocation(latitude: location.lat, longitude: location.lon)
if let city = try? await geocoder.reverseGeocodeLocation(location)
.first
.flatMap({ placemark in
placemark.locality
})
{
text = city
}
else {
text = Self.noCityText
}
}
}
struct ContentView2: View {
let location: Location
#State var config = ContentView2Config()
var body: some View {
Text(config.text)
.task(id: location.id) {
await config.reverseGeocode(location: location)
}
}
}
And in case it helps, here is the location manager:
struct Location: Identifiable {
let id = UUID()
let lat: Double
let lon: Double
}
class Locator: NSObject, ObservableObject, CLLocationManagerDelegate {
#Published var location: Location?
let locationManager = CLLocationManager()
override init() {
super.init()
locationManager.delegate = self
locationManager.startUpdatingLocation()
locationManager.requestWhenInUseAuthorization()
}
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
guard let coordinate = locations.last?.coordinate else {
location = nil
return
}
location = Location(lat: coordinate.latitude, lon: coordinate.longitude)
}
func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
location = nil
}
}