locationManager.requestWhenInUseAuthorization()没有位置权限弹出

Question

我遵循一个在线教程来制作一个简单的项目，在地图上显示用户的位置。但是，当我运行它时，不会显示用户位置，也不会弹出请求位置权限。我不知道我怎么能解决这个问题。我已经把密码附在下面。

import MapKit
import SwiftUI

struct ContentView: View {
    @StateObject private var viewModel=ContentViewModel()
    
    var body: some View {
        Map(coordinateRegion: $viewModel.region)
            .ignoresSafeArea()
            .onAppear{viewModel.checkIfLocationServicesIsEnabled()}
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

final class ContentViewModel: NSObject, ObservableObject, CLLocationManagerDelegate{
    @Published var region = MKCoordinateRegion(center: CLLocationCoordinate2D(latitude:37.3331516, longitude: -121.891054), span: MKCoordinateSpan(latitudeDelta: 0.1, longitudeDelta: 0.1));
    var locationManager: CLLocationManager?
    func checkIfLocationServicesIsEnabled(){
        if CLLocationManager.locationServicesEnabled(){
            locationManager=CLLocationManager()
            locationManager!.delegate=self
        }
        else{
            print("Turn location on")
        }
    }
    private func checkLocationAuthorization(){
        guard let locationManager = locationManager else {
            return
        }
        switch locationManager.authorizationStatus{
        case.notDetermined:
            locationManager.requestWhenInUseAuthorization()
        case .restricted:
            print("Your location is restricted likely due to parental controls.")
        case .denied:
            print("You have denied this app location permission. Go into settings to change it.")
        case .authorizedAlways:
            region=MKCoordinateRegion(center: locationManager.location!.coordinate, span:MKCoordinateSpan(latitudeDelta: 0.1, longitudeDelta: 0.1))
        case .authorizedWhenInUse:
            region=MKCoordinateRegion(center: locationManager.location!.coordinate, span:MKCoordinateSpan(latitudeDelta: 0.1, longitudeDelta: 0.1))
        @unknown default:
            break
        }
        func locationManagerDidChangeAuthorization(_manager: CLLocationManager) {
            checkLocationAuthorization()
            
        }
    }
}

Answer 1

您的代码有两个问题

您不是要求permissions.

• You实现委托错误的

1. .

这应该是可行的：

final class ContentViewModel: NSObject, ObservableObject, CLLocationManagerDelegate{
    @Published var region = MKCoordinateRegion(center: CLLocationCoordinate2D(latitude:37.3331516, longitude: -121.891054), span: MKCoordinateSpan(latitudeDelta: 0.1, longitudeDelta: 0.1));
    var locationManager: CLLocationManager?
    
   
    func checkIfLocationServicesIsEnabled(){
        if CLLocationManager.locationServicesEnabled(){
            locationManager=CLLocationManager()
            locationManager?.delegate=self
            //ask for permissions here
            //depending on your usage you could also ask for 
            //locationManager?.requestWhenInUseAuthorization()
            locationManager?.requestAlwaysAuthorization()
        }
        else{
            print("Turn location on")
        }
    }
    private func checkLocationAuthorization(){
        guard let locationManager = locationManager else {
            return
        }
        switch locationManager.authorizationStatus{
        case.notDetermined:
            //the function containing this will only be called if the permission get requested so remove it
            //locationManager.requestWhenInUseAuthorization()
        case .restricted:
            print("Your location is restricted likely due to parental controls.")
        case .denied:
            print("You have denied this app location permission. Go into settings to change it.")
        case .authorizedAlways:
            region=MKCoordinateRegion(center: locationManager.location!.coordinate, span:MKCoordinateSpan(latitudeDelta: 0.1, longitudeDelta: 0.1))
        case .authorizedWhenInUse:
            region=MKCoordinateRegion(center: locationManager.location!.coordinate, span:MKCoordinateSpan(latitudeDelta: 0.1, longitudeDelta: 0.1))
        @unknown default:
            break
        }
    }
    // this function was wrapped inside your checkLocationAuthorization() function
    //move it to outer scope. It gets called every time you request permissions
    func locationManagerDidChangeAuthorization(_ manager: CLLocationManager) {
        checkLocationAuthorization()
        
    }
}

请注意，您将不得不添加多个隐私密钥，以使这一工作。