有许多示例展示了如何进行反向地理定位,但最近没有在 SwiftUI 中实现。我当前的代码使用 iPhone GPS 生成与地图一起使用的坐标以显示位置。我还想显示街道地址,因为没有指示位置的文字的地图不是很有帮助。
我的问题:
- 我是否拥有实现反向地理定位的所有相关代码?
- 我已经看到使用故事板和打印语句来显示位置的示例,但是如何将位置返回到带有 @escaping 闭包的 Swiftui 视图?
import Foundation
import CoreLocation
class LocationManager: NSObject, ObservableObject {
private let locationManager = CLLocationManager()
@Published var currentAddress: String = ""
override init() {
super.init()
self.locationManager.delegate = self
self.locationManager.distanceFilter = 10 // distance before update (meters)
self.locationManager.requestWhenInUseAuthorization()
self.locationManager.desiredAccuracy = kCLLocationAccuracyBest
self.locationManager.startUpdatingLocation()
}
func startLocationServices() {
if locationManager.authorizationStatus == .authorizedAlways || locationManager.authorizationStatus == .authorizedWhenInUse {
locationManager.startUpdatingLocation()
} else {
locationManager.requestWhenInUseAuthorization()
}
}
func getLocationCoordinates() -> (Double, Double) {
let coordinate = self.locationManager.location != nil ? self.locationManager.location!.coordinate : CLLocationCoordinate2D()
print("location = \(coordinate.latitude), \(coordinate.longitude)")
return (Double(coordinate.latitude), Double(coordinate.longitude))
}
// Using closure
func getAddress(handler: @escaping (String) -> Void)
{
self.currentAddress = ""
let coordinate = self.locationManager.location != nil ? self.locationManager.location!.coordinate : CLLocationCoordinate2D()
let location = CLLocation(latitude: coordinate.latitude, longitude: coordinate.longitude)
let geoCoder = CLGeocoder()
geoCoder.reverseGeocodeLocation(location, completionHandler: { (placemarks, error) -> Void in
// Place details
var placeMark: CLPlacemark?
placeMark = placemarks?[0]
guard let placemark = placemarks?.first else { return }
if let streetNumber = placemark.subThoroughfare,
let street = placemark.subThoroughfare,
let city = placemark.locality,
let state = placemark.administrativeArea {
DispatchQueue.main.async {
self.currentAddress = "\(streetNumber) \(street) \(city) \(state)"
}
} else if let city = placemark.locality, let state = placemark.administrativeArea {
DispatchQueue.main.async {
self.currentAddress = "\(city) \(state)"
}
} else {
DispatchQueue.main.async {
self.currentAddress = "Address Unknown"
}
}
}
)
print( self.currentAddress)
}
}
extension LocationManager: CLLocationManagerDelegate {
func locationManagerDidChangeAuthorization(_ manager: CLLocationManager) {
if locationManager.authorizationStatus == .authorizedAlways || locationManager.authorizationStatus == .authorizedWhenInUse {
locationManager.startUpdatingLocation()
}
}
// Get Placemark
func getPlace(for location: CLLocation,
completion: @escaping (CLPlacemark?) -> Void) {
let geocoder = CLGeocoder()
geocoder.reverseGeocodeLocation(location) { placemarks, error in
guard error == nil else {
print("*** Error in \(#function): \(error!.localizedDescription)")
completion(nil)
return
}
guard let placemark = placemarks?[0] else {
print("*** Error in \(#function): placemark is nil")
completion(nil)
return
}
completion(placemark)
}
}
}
如果我在 ContentView 中添加以下代码:
@State private var entryLat: Double = 0.0
@State private var entryLong: Double = 0.0
let result = lm.getLocationCoordinates()
entryLat = result.0
entryLong = result.1
我怎么称呼 getPlace?