I am trying to call model form #main App where the model has the dependency on a repository with init function. The repository has the URLSession and Baseurl properties . I have passed the required property on both approach ..
Here is approach I have tried based on Xcode suggestions ..
#main
struct HomwWorkWithSwiftUIApp: App {
#StateObject var model = FruitsModel(fruitRepository: FruitsRepository.self as! FruitsRepository)
var body: some Scene {
WindowGroup {
ContentView().environmentObject(model)
}
}
}
As a result as was crashed at run time with error Thread 1: signal SIGABRT
The second approach is passing the require parameters like this ..
#main
struct HomwWorkWithSwiftUIApp: App {
#StateObject var model = FruitsModel(fruitRepository: RealFruitsRepository(session: URLSession, baseURL: EndPoint.baseUrl))
var body: some Scene {
WindowGroup {
ContentView().environmentObject(model)
}
}
}
It giving error ..Cannot convert value of type 'URLSession.Type' to expected argument type 'URLSession'
Here is attempt for URLSession instance.
#main
struct HomwWorkWithSwiftUIApp: App {
init() {
}
var url : URLSession
init(url: URLSession) {
self.url = url
}
#StateObject var model = FruitsModel(fruitRepository: RealFruitsRepository(session: url, baseURL: EndPoint.baseUrl))
var body: some Scene {
WindowGroup {
ContentView().environmentObject(model)
}
}
}
Here is the screenshot ..
Here is the repository code ..
import Foundation
protocol FruitsRepository: WebRepository {
func loadFruits() async throws -> [Fruits]
}
struct RealFruitsRepository: FruitsRepository {
let session: URLSession
let baseURL: String
init(session: URLSession, baseURL: String) {
self.session = session
self.baseURL = baseURL
}
func loadFruits() async throws -> [Fruits] {
guard let request = try? API.allFruits.urlRequest(baseURL: baseURL) else {
throw APIError.invalidURL
}
guard let data = try? await call(request: request) else {
throw APIError.unexpectedResponse
}
guard let fruits = getDecodedFruitesResopnse(from: data) else {
throw APIError.unexpectedResponse
}
return fruits
}
private func getDecodedFruitesResopnse(from data: Data)-> [Fruits]? {
guard let fruites = try? JSONDecoder().decode([Fruits].self, from: data) else {
return nil
}
return fruites
}
}
extension RealFruitsRepository {
enum API {
case allFruits
case fruitDetails(Fruits)
}
}
extension RealFruitsRepository.API: APICall {
var path: String {
switch self {
case .allFruits:
return "/all"
case let .fruitDetails(fruit):
let encodedName = fruit.name.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed)
return "/name/\(encodedName ?? fruit.name)"
}
}
var method: String {
switch self {
case .allFruits, .fruitDetails:
return "GET"
}
}
var headers: [String: String]? {
return ["Accept": "application/json"]
}
func body() throws -> Data? {
return nil
}
}
Here is the model class ..
import Foundation
import Combine
protocol FruitsModelInput {
func getFruits() async
}
protocol FruitsModelOutput {
var state: FruitViewStates { get }
var fruitRecordsCount: Int { get }
func getFruit(index: Int)-> Fruits
func getFruitsDetails(for row:Int)-> FruitsDetails
}
struct FruitsDetails {
let genus, name: String
}
final class FruitsModel: ObservableObject {
private var fruitsRepository: FruitsRepository
var fruits: [Fruits] = []
#Published var state: FruitViewStates = .none
private var cancellables:Set<AnyCancellable> = Set()
init(fruitRepository: FruitsRepository) {
self.fruitsRepository = fruitRepository
}
}
extension FruitsModel: FruitsModelOutput {
func getFruitsDetails(for row: Int) -> FruitsDetails {
if row >= 0 {
let fruit = fruits[row]
return FruitsDetails(genus: fruit.genus, name: fruit.name)
}
return FruitsDetails(genus: "", name: "")
}
var fruitRecordsCount: Int {
return fruits.count
}
func getFruit(index: Int) -> Fruits {
if fruits.count > 0 {
return (fruits[index])
} else {
return Fruits(genus: "", name: "", id: 0, family: "", order: "", nutritions: Nutritions(carbohydrates: 0.0, protein: 0.0, fat: 0.0, calories: 0, sugar: 0.0))
}
}
}
extension FruitsModel: FruitsModelInput {
func getFruits() async {
state = .showActivityIndicator
do {
fruits = try await fruitsRepository.loadFruits()
self.state = .showFruitList
} catch let error {
fruits = []
print(error)
state = .showError((error as! APIError).localizedDescription)
}
}
}
Here is how I add new entity.
func addCountry(name: String, code: String, flagImageUri: String?, wikiDataId: String) {
let newCountry = CountryEntity(context: container.viewContext)
newCountry.name = name
newCountry.code = code
newCountry.flagImageUri = flagImageUri
newCountry.wikiDataId = wikiDataId
save()
}
Here is my data:
However when I use the add function in my view, I got this error:
CoreData: error: +[CountryEntity entity] Failed to find a unique match for an NSEntityDescription to a managed object subclass
And this is my button:
Button(action: {
country.isFaved = !country.isFaved
coreDataModel.addCountry(name: country.name, code: country.code, flagImageUri: country.flagImageUri, wikiDataId: country.wikiDataId)
}) {
Image(systemName: "star.fill")
.foregroundColor(country.isFaved ? .black : .white)
.scaledToFit()
}
This is the whole class. I'm fetching, saving ,adding and deleting all data here. I did everything like the video I watched in youtube.
class DataController: ObservableObject {
let container = NSPersistentContainer(name: "CountryCoreData")
#Published var savedCountries: [CountryEntity] = []
init() {
container.loadPersistentStores(completionHandler: { _, error in
if let error = error {
print("CoreData failed to load: \(error.localizedDescription)")
} else {
print("Successfully loaded")
}
})
}
func fetchCountries() -> [CountryEntity]? {
let request = NSFetchRequest<CountryEntity>(entityName: "CountryEntity")
do {
let fetchedCountries = try container.viewContext.fetch(request)
return fetchedCountries
} catch {
print("Something went wrong while data fetching \(error)")
return nil
}
}
func delete(code: String) {
guard let fetchedCountries = fetchCountries() else { return }
for country in fetchedCountries {
if country.code!.contains(code) {
container.viewContext.delete(country)
save()
}
}
}
func addCountry(name: String, code: String, flagImageUri: String?, wikiDataId: String) {
let newCountry = CountryEntity(context: container.viewContext)
print("OSMAN")
newCountry.name = name
newCountry.code = code
newCountry.flagImageUri = flagImageUri
newCountry.wikiDataId = wikiDataId
save()
}
func save() {
do {
try container.viewContext.save()
fetchCountries()
} catch {
print("Error while saving the data: \(error)")
}
}
}
How can I solve this problem?
Code from tutorial, want to access contacts from my app, and using this as base
Need to solve this error to move forward and do not know what additional items needs initialization. Any help very appreciated.
import Contacts
final class ContactsViewModel: ObservableObject {
#Published
var contact: [Contact?]
#Published
var contacts: [Contact?] = []
#Published
var permissionsError: PermissionsError? = .none
init( contact: Contact, contacts: [Contact] , permissionsError: PermissionsError) {
permissions()
}. **<-- Error occurs here -**
func openSettings() {
permissionsError = .none
guard let settingsURL = URL(string: UIApplication.openSettingsURLString) else {return}
if UIApplication.shared.canOpenURL(settingsURL) { UIApplication.shared.open(settingsURL)}
}
func getContacts() {
Contact.fetchAll { [weak self] result in
guard let self = self else { return }
switch result {
case .success(let fetchedContacts):
DispatchQueue.main.async {
self.contacts = fetchedContacts.sorted(by: { $0.lastName < $1.lastName })
}
case .failure(let error):
self.permissionsError = .fetchError(error)
}
}
}
func permissions() {
switch CNContactStore.authorizationStatus(for: .contacts) {
case.authorized:
getContacts()
case .notDetermined, .restricted, .denied :
CNContactStore().requestAccess(for: .contacts) { [weak self] granted, error in
switch granted {
case true: self?.getContacts()
case false:
DispatchQueue.main.async {
self?.permissionsError = .userError
}
}
}
I am classifying images per frame from ARSession delegate by Vision framework and CoreML in an Augmented Reality app, with ARKit and RealityKit. While processing a frame.capturedImage I am not requesting another frame.capturedImage for performance.
The camera is not giving smooth experience, it gets stuck time to time. Seems like a frame loss.
And I am getting this Warning:
[Session] ARSession <0x122cc3710>: ARSessionDelegate is retaining 14 ARFrames. This can lead to future camera frames being dropped.
My Codes:
import Foundation
import SwiftUI
import RealityKit
import ARKit
import CoreML
struct ARViewContainer: UIViewRepresentable {
var errorFunc: ()->Void
var frameUpdateFunc: ()->Void
#Binding var finalLabel:String
func makeUIView(context: Context) -> ARView {
let arView = ARView(frame: .zero)
let config = ARWorldTrackingConfiguration()
config.planeDetection = [.horizontal,.vertical]
config.environmentTexturing = .automatic
if ARWorldTrackingConfiguration.supportsSceneReconstruction(.mesh){
config.sceneReconstruction = .mesh
}
arView.session.delegate = context.coordinator
arView.session.run(config)
context.coordinator.myView = arView
return arView
}
func updateUIView(_ uiView: ARView, context: Context) {
}
func makeCoordinator() -> Coordinator {
Coordinator(finalLabel: $finalLabel, self, funct: self.errorFunc, frameUpdateFunc: self.frameUpdateFunc)
}
class Coordinator: NSObject, ARSessionDelegate {
var objectDetectionService = ObjectDetectionService()
var myView:ARView?
#Binding var finalLabel:String
var parent: ARViewContainer
var efunc:()->Void
var frameUpdateFunc:()->Void
var isLoopShouldContinue = true
var lastLocation: SCNVector3?
//let model = try? MobileNetV2(configuration: .init())
private let classifier = VisionClasifier(mlModel: try? MobileNetV2(configuration: .init()).model)
private var currentBuffer: CVPixelBuffer? = nil
init(finalLabel:Binding<String>,_ arView: ARViewContainer,funct: #escaping ()->Void, frameUpdateFunc:#escaping ()->Void) {
parent = arView
self.efunc = funct
self.frameUpdateFunc = frameUpdateFunc
_finalLabel = finalLabel
}
func session(_ session: ARSession, didFailWithError error: Error) {
//print("Error Tanvir: ",error)
self.efunc()
}
func session(_ session: ARSession, didUpdate frame: ARFrame) {
if isLoopShouldContinue{
self.classifyFrame(currentFrame: frame)
}
let transform = SCNMatrix4(frame.camera.transform)
let orientation = SCNVector3(-transform.m31, -transform.m32, transform.m33)
let location = SCNVector3(transform.m41, transform.m42, transform.m43)
let currentPositionOfCamera = orientation + location
if let lastLocation = lastLocation {
let speed = (lastLocation - currentPositionOfCamera).length()
isLoopShouldContinue = speed < 0.0025
}
lastLocation = currentPositionOfCamera
}
// When ARKit detects a new anchor, it will add it to the ARSession
// Whenever there is a newly added ARAnchor, you will get that anchor here.
// In this short tutorial, we will target the ARPlaneAnchor, and use the information stored
// in that anchor for visualization.
func session(_ session: ARSession, didAdd anchors: [ARAnchor]) {
guard let myView = myView else {
return
}
for anchor in anchors {
if anchor is ARPlaneAnchor {
let planeAnchor = anchor as! ARPlaneAnchor
//addPlaneEntity(with: planeAnchor, to: myView)
}
}
}
// ARKit will automatically track and update the ARPlaneAnchor.
// We use that anchor to update the `skin` of the plane.
func session(_ session: ARSession, didUpdate anchors: [ARAnchor]) {
guard let myView = myView else {
return
}
for anchor in anchors {
if anchor is ARPlaneAnchor {
let planeAnchor = anchor as! ARPlaneAnchor
//updatePlaneEntity(with: planeAnchor, in: myView)
}
}
}
// When ARKit remove an anchor from the ARSession, you will get the removed
// anchor here.
func session(_ session: ARSession, didRemove anchors: [ARAnchor]) {
guard let myView = myView else {
return
}
for anchor in anchors {
if anchor is ARPlaneAnchor {
let planeAnchor = anchor as! ARPlaneAnchor
//removePlaneEntity(with: planeAnchor, from: myView)
}
}
}
func addAnnotation(rectOfInterest rect: CGRect, text: String,width:Float,height:Float) {
let point = CGPoint(x: rect.midX, y: rect.midY)
print("point:", point)
//let scnHitTestResults = myView.hitTest(point,
// options: [SCNHitTestOption.searchMode: SCNHitTestSearchMode.all.rawValue])
//guard !scnHitTestResults.contains(where: { $0.node.name == BubbleNode.name }) else { return }
let raycastResult = myView!.raycast(from: point, allowing: .estimatedPlane, alignment: .any)
// guard let raycastQuery = myView!.raycastQuery(from: point,
// allowing: .existingPlaneInfinite,
// alignment: .horizontal),
// let raycastResult = myView.session.raycast(raycastQuery).first else { return }
guard let raycastResult = raycastResult.first else{
print("raycast result failed")
return
}
let anchorExists = myView!.scene.anchors.contains(where: {$0.name == text})
guard anchorExists == false else{
print("anchor Already exists")
return
}
let position = raycastResult.worldTransform.columns.3
let myEntity = create2dEntity(with: position, boundingBox: rect, raycastResult: raycastResult,width:width ,height:height)
let planeAnchorEntity = AnchorEntity()
planeAnchorEntity.name = text
planeAnchorEntity.position = simd_make_float3(position)
planeAnchorEntity.addChild(myEntity)
// Finally, add the entity to scene.
myView!.scene.addAnchor(planeAnchorEntity)
print("anchor added: ", planeAnchorEntity.name)
}
func classifyFrame(currentFrame:ARFrame){
//let currentImageName = photos[currentIndex]
// 2
// 3
print("inside Classify")
//print("CurrentBuffer", currentBuffer)
guard self.currentBuffer == nil else {
//print("CurrentBuffer: ",currentBuffer)
//self.finalLabel = "current buffer problem"
return
}
self.currentBuffer = currentFrame.capturedImage
// guard let model = self.model else {
// return "Model not Found."
// }
let img = CIImage(cvImageBuffer: currentFrame.capturedImage)
let cgImage = convertCIImageToCGImage(inputImage: img)
guard let cgImage = cgImage else{
print("can not convert CGImage")
self.finalLabel = "can not convert CGImage"
return
}
objectDetectionService.detect(on: .init(pixelBuffer: currentFrame.capturedImage)) { [weak self] result in
guard let self = self else { return }
switch result {
case .success(let response):
self.finalLabel = response.classification.description
print("Real Width: ",response.boundingBox.width)
let rectOfInterest = VNImageRectForNormalizedRect(
response.boundingBox,
Int(self.myView!.bounds.width),
Int(self.myView!.bounds.height))
self.addAnnotation(rectOfInterest: rectOfInterest, text: response.classification.description,width: Float(response.boundingBox.width),height: Float(response.boundingBox.height))
print("Success:",response.classification.description)
self.currentBuffer = nil
case .failure(let error):
self.finalLabel = "Detection Failed"
print("Detection failure: ",error.localizedDescription)
self.currentBuffer = nil
break
}
}
}
}
}
func convertCIImageToCGImage(inputImage: CIImage) -> CGImage? {
let context = CIContext(options: nil)
if let cgImage = context.createCGImage(inputImage, from: inputImage.extent) {
return cgImage
}
return nil
}
// The ARPlaneAnchor contains the information we need to create the `skin` of the plane.
func addPlaneEntity(with anchor: ARPlaneAnchor, to view: ARView) {
let planeAnchorEntity = AnchorEntity(.plane([.any],
classification: [.any],
minimumBounds: [0.01, 0.01]))
let planeModelEntity = createPlaneModelEntity(with: anchor)
// Give Entity a name for tracking.
planeAnchorEntity.name = anchor.identifier.uuidString + "_anchor"
planeModelEntity.name = anchor.identifier.uuidString + "_model"
// Add ModelEntity as a child of AnchorEntity.
// AnchorEntity handles `position` of the plane.
// ModelEntity handles the `skin` of the plane.
planeAnchorEntity.addChild(planeModelEntity)
// Finally, add the entity to scene.
view.scene.addAnchor(planeAnchorEntity)
}
func create2dEntity(with position: simd_float4, boundingBox: CGRect, raycastResult:ARRaycastResult, width:Float,height:Float ) -> ModelEntity{
var planeMesh: MeshResource
var color: UIColor
print("horizotal plane")
color = UIColor.red.withAlphaComponent(0.5)
print("Constant width: 0.1 but BoundingBox Width: ",boundingBox.width)
planeMesh = .generatePlane(width: 0.1, height: 0.1)
return ModelEntity(mesh: planeMesh, materials: [SimpleMaterial(color: color, roughness: 0.25, isMetallic: false)])
}
func createPlaneModelEntity(with anchor: ARPlaneAnchor) -> ModelEntity {
var planeMesh: MeshResource
var color: UIColor
if anchor.alignment == .horizontal {
print("horizotal plane")
color = UIColor.blue.withAlphaComponent(0.5)
planeMesh = .generatePlane(width: anchor.extent.x, depth: anchor.extent.z)
} else if anchor.alignment == .vertical {
print("vertical plane")
color = UIColor.yellow.withAlphaComponent(0.5)
planeMesh = .generatePlane(width: anchor.extent.x, height: anchor.extent.z)
} else {
fatalError("Anchor is not ARPlaneAnchor")
}
return ModelEntity(mesh: planeMesh, materials: [SimpleMaterial(color: color, roughness: 0.25, isMetallic: false)])
}
func removePlaneEntity(with anchor: ARPlaneAnchor, from arView: ARView) {
guard let planeAnchorEntity = arView.scene.findEntity(named: anchor.identifier.uuidString+"_anchor") else { return }
arView.scene.removeAnchor(planeAnchorEntity as! AnchorEntity)
}
func updatePlaneEntity(with anchor: ARPlaneAnchor, in view: ARView) {
var planeMesh: MeshResource
guard let entity = view.scene.findEntity(named: anchor.identifier.uuidString+"_model") else { return }
let modelEntity = entity as! ModelEntity
if anchor.alignment == .horizontal {
planeMesh = .generatePlane(width: anchor.extent.x, depth: anchor.extent.z)
} else if anchor.alignment == .vertical {
planeMesh = .generatePlane(width: anchor.extent.x, height: anchor.extent.z)
} else {
fatalError("Anchor is not ARPlaneAnchor")
}
modelEntity.model!.mesh = planeMesh
}
import SceneKit
extension SCNVector3 {
func length() -> Float {
return sqrtf(x * x + y * y + z * z)
}
}
func -(l: SCNVector3, r: SCNVector3) -> SCNVector3 {
return SCNVector3Make(l.x - r.x, l.y - r.y, l.z - r.z)
}
func +(l: SCNVector3, r: SCNVector3) -> SCNVector3 {
return SCNVector3(l.x + r.x, l.y + r.y, l.z + r.z)
}
func /(l: SCNVector3, r: Float) -> SCNVector3 {
return SCNVector3(l.x / r, l.y / r, l.z / r)
}
Detection: (Here is the problem, I guess, in detect method)
import Foundation
import UIKit
import CoreML
import Vision
import SceneKit
class ObjectDetectionService {
var mlModel = try! VNCoreMLModel(for: YOLOv3Int8LUT().model)
//let model = try? YOLOv3Int8LUT(configuration: .init())
lazy var coreMLRequest: VNCoreMLRequest = {
return VNCoreMLRequest(model: mlModel,
completionHandler: self.coreMlRequestHandler)
}()
private var completion: ((Result<Response, Error>) -> Void)?
func detect(on request: Request, completion: #escaping (Result<Response, Error>) -> Void) {
self.completion = completion
//let orientation = .up
let imageRequestHandler = VNImageRequestHandler(cvPixelBuffer: request.pixelBuffer)
do {
try imageRequestHandler.perform([coreMLRequest])
} catch {
self.complete(.failure(error))
return
}
}
}
private extension ObjectDetectionService {
func coreMlRequestHandler(_ request: VNRequest?, error: Error?) {
if let error = error {
complete(.failure(error))
return
}
guard let request = request, let results = request.results as? [VNRecognizedObjectObservation] else {
complete(.failure(RecognitionError.resultIsEmpty))
return
}
guard let result = results.first(where: { $0.confidence > 0.8 }),
let classification = result.labels.first else {
complete(.failure(RecognitionError.lowConfidence))
return
}
let response = Response(boundingBox: result.boundingBox,
classification: classification.identifier)
complete(.success(response))
}
func complete(_ result: Result<Response, Error>) {
DispatchQueue.main.async {
self.completion?(result)
self.completion = nil
}
}
}
enum RecognitionError: Error {
case unableToInitializeCoreMLModel
case resultIsEmpty
case lowConfidence
}
extension ObjectDetectionService {
struct Request {
let pixelBuffer: CVPixelBuffer
}
struct Response {
let boundingBox: CGRect
let classification: String
}
}
Why am I getting this warning, and How to get the camera smooth experience?
The session(_ session: ARSession, didUpdate frame: ARFrame) delegate method is called very frequently: many times per second. If your classifyFrame method is doing too much work, it will retain the ARFrame object until after the next frame is delivered to the delegate.
ARKit will warn you when too many frames are retained, typically because a queue is blocked in your delegate.
There are a number of examples showing how to do reverse geolocation, but nothing recent on implementation in SwiftUI. My current code uses the iPhone GPS to generate coordinates that are used with maps to show the location. I would also like to display the street address since a map without text indicating the location isn't very helpful.
My Questions:
Do I have all the relevant code to implement reverse geolocation?
I have seen examples using storyboards and print statements to display the location, but how do I return the location to a Swiftui view with an #escaping closure?
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)
}
}
}
If I add the follow code say in ContentView:
#State private var entryLat: Double = 0.0
#State private var entryLong: Double = 0.0
let result = lm.getLocationCoordinates()
entryLat = result.0
entryLong = result.1
How would I call getPlace?
To use the following code you need to setup the appropriate entitlements and authorizations.
Here is a working example of using geolocation in swiftui, from code I got from
a number of sources on the net years ago.
This should give you a base to do reverse geolocation in swiftui:
import Foundation
import CoreLocation
import SwiftUI
import Combine
#main
struct TestApp: App {
var body: some Scene {
WindowGroup {
ContentView()
}
}
}
struct ContentView: View {
let locationProvider = LocationProvider()
#State var currentAddress = ""
var body: some View {
Text(currentAddress)
.onAppear {
getAddress()
}
}
func getAddress() {
// for testing Tokyo
let location = CLLocation(latitude: 35.684602, longitude: 139.751992)
locationProvider.getPlace(for: location) { plsmark in
guard let placemark = plsmark else { return }
if let streetNumber = placemark.subThoroughfare,
let street = placemark.subThoroughfare,
let city = placemark.locality,
let state = placemark.administrativeArea {
self.currentAddress = "\(streetNumber) \(street) \(city) \(state)"
} else if let city = placemark.locality, let state = placemark.administrativeArea {
self.currentAddress = "\(city) \(state)"
} else {
self.currentAddress = "Address Unknown"
}
}
}
}
/**
A Combine-based CoreLocation provider.
On every update of the device location from a wrapped `CLLocationManager`,
it provides the latest location as a published `CLLocation` object and
via a `PassthroughSubject<CLLocation, Never>` called `locationWillChange`.
*/
public class LocationProvider: NSObject, ObservableObject {
private let lm = CLLocationManager()
/// Is emitted when the `location` property changes.
public let locationWillChange = PassthroughSubject<CLLocation, Never>()
/**
The latest location provided by the `CLLocationManager`.
Updates of its value trigger both the `objectWillChange` and the `locationWillChange` PassthroughSubjects.
*/
#Published public private(set) var location: CLLocation? {
willSet {
locationWillChange.send(newValue ?? CLLocation())
}
}
/// The authorization status for CoreLocation.
#Published public var authorizationStatus: CLAuthorizationStatus?
/// A function that is executed when the `CLAuthorizationStatus` changes to `Denied`.
public var onAuthorizationStatusDenied : ()->Void = {presentLocationSettingsAlert()}
/// The LocationProvider intializer.
///
/// Creates a CLLocationManager delegate and sets the CLLocationManager properties.
public override init() {
super.init()
self.lm.delegate = self
self.lm.desiredAccuracy = kCLLocationAccuracyBest
self.lm.activityType = .fitness
self.lm.distanceFilter = 10
self.lm.allowsBackgroundLocationUpdates = true
self.lm.pausesLocationUpdatesAutomatically = false
self.lm.showsBackgroundLocationIndicator = true
}
/**
Request location access from user.
In case, the access has already been denied, execute the `onAuthorizationDenied` closure.
The default behavior is to present an alert that suggests going to the settings page.
*/
public func requestAuthorization() -> Void {
if self.authorizationStatus == CLAuthorizationStatus.denied {
onAuthorizationStatusDenied()
}
else {
self.lm.requestWhenInUseAuthorization()
}
}
/// Start the Location Provider.
public func start() throws -> Void {
self.requestAuthorization()
if let status = self.authorizationStatus {
guard status == .authorizedWhenInUse || status == .authorizedAlways else {
throw LocationProviderError.noAuthorization
}
}
else {
/// no authorization set by delegate yet
#if DEBUG
print(#function, "No location authorization status set by delegate yet. Try to start updates anyhow.")
#endif
/// In principle, this should throw an error.
/// However, this would prevent start() from running directly after the LocationProvider is initialized.
/// This is because the delegate method `didChangeAuthorization`,
/// setting `authorizationStatus` runs only after a brief delay after initialization.
//throw LocationProviderError.noAuthorization
}
self.lm.startUpdatingLocation()
}
/// Stop the Location Provider.
public func stop() -> Void {
self.lm.stopUpdatingLocation()
}
// todo deal with errors
public func getPlace(for location: CLLocation, completion: #escaping (CLPlacemark?) -> Void) {
let geocoder = CLGeocoder()
geocoder.reverseGeocodeLocation(location) { placemarks, error in
guard error == nil else {
print("=====> Error \(error!.localizedDescription)")
completion(nil)
return
}
guard let placemark = placemarks?.first else {
print("=====> Error placemark is nil")
completion(nil)
return
}
completion(placemark)
}
}
}
/// Present an alert that suggests to go to the app settings screen.
public func presentLocationSettingsAlert(alertText : String? = nil) -> Void {
let alertController = UIAlertController (title: "Enable Location Access", message: alertText ?? "The location access for this app is set to 'never'. Enable location access in the application settings. Go to Settings now?", preferredStyle: .alert)
let settingsAction = UIAlertAction(title: "Settings", style: .default) { (_) -> Void in
guard let settingsUrl = URL(string:UIApplication.openSettingsURLString) else {
return
}
UIApplication.shared.open(settingsUrl)
}
alertController.addAction(settingsAction)
let cancelAction = UIAlertAction(title: "Cancel", style: .default, handler: nil)
alertController.addAction(cancelAction)
UIApplication.shared.windows[0].rootViewController?.present(alertController, animated: true, completion: nil)
}
/// Error which is thrown for lacking localization authorization.
public enum LocationProviderError: Error {
case noAuthorization
}
extension LocationProvider: CLLocationManagerDelegate {
public func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
self.authorizationStatus = status
#if DEBUG
print(#function, status.name)
#endif
//print()
}
public func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
guard let location = locations.last else { return }
self.location = location
}
public func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
if let clErr = error as? CLError {
switch clErr {
case CLError.denied : do {
print(#function, "Location access denied by user.")
self.stop()
self.requestAuthorization()
}
case CLError.locationUnknown : print(#function, "Location manager is unable to retrieve a location.")
default: print(#function, "Location manager failed with unknown CoreLocation error.")
}
}
else {
print(#function, "Location manager failed with unknown error", error.localizedDescription)
}
}
}
extension CLAuthorizationStatus {
/// String representation of the CLAuthorizationStatus
var name: String {
switch self {
case .notDetermined: return "notDetermined"
case .authorizedWhenInUse: return "authorizedWhenInUse"
case .authorizedAlways: return "authorizedAlways"
case .restricted: return "restricted"
case .denied: return "denied"
default: return "unknown"
}
}
}