Lekce 9: Lokační služby

DevAcademy.xcodeproj/project.pbxproj

@@ -18,6 +18,7 @@
 		84FA93B72A68317F00DFC974 /* Point.swift in Sources */ = {isa = PBXBuildFile; fileRef = 84FA93B62A68317F00DFC974 /* Point.swift */; };
 		84FA93B92A68319800DFC974 /* Properties.swift in Sources */ = {isa = PBXBuildFile; fileRef = 84FA93B82A68319800DFC974 /* Properties.swift */; };
 		BE1E12592AA5C6CB000BA3D8 /* StoreadAsyncImage.swift in Sources */ = {isa = PBXBuildFile; fileRef = BE1E12582AA5C6CB000BA3D8 /* StoreadAsyncImage.swift */; };
+		BE38A88A2AA7294400EB5431 /* UserLocationService.swift in Sources */ = {isa = PBXBuildFile; fileRef = BE38A8892AA7294400EB5431 /* UserLocationService.swift */; };
 		BEEF9EC12A67C74E002126F4 /* PlacesService.swift in Sources */ = {isa = PBXBuildFile; fileRef = BEEF9EC02A67C74E002126F4 /* PlacesService.swift */; };
 		C05610492A5C78CA007FB970 /* DevAcademyApp.swift in Sources */ = {isa = PBXBuildFile; fileRef = C05610482A5C78CA007FB970 /* DevAcademyApp.swift */; };
 		C056104B2A5C78CA007FB970 /* RootView.swift in Sources */ = {isa = PBXBuildFile; fileRef = C056104A2A5C78CA007FB970 /* RootView.swift */; };
@@ -44,6 +45,8 @@
 		84FA93B62A68317F00DFC974 /* Point.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Point.swift; sourceTree = "<group>"; };
 		84FA93B82A68319800DFC974 /* Properties.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Properties.swift; sourceTree = "<group>"; };
 		BE1E12582AA5C6CB000BA3D8 /* StoreadAsyncImage.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = StoreadAsyncImage.swift; sourceTree = "<group>"; };
+		BE38A8882AA7285B00EB5431 /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist; path = Info.plist; sourceTree = "<group>"; };
+		BE38A8892AA7294400EB5431 /* UserLocationService.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UserLocationService.swift; sourceTree = "<group>"; };
 		BEEF9EC02A67C74E002126F4 /* PlacesService.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PlacesService.swift; sourceTree = "<group>"; };
 		C05610452A5C78CA007FB970 /* DevAcademy.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = DevAcademy.app; sourceTree = BUILT_PRODUCTS_DIR; };
 		C05610482A5C78CA007FB970 /* DevAcademyApp.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DevAcademyApp.swift; sourceTree = "<group>"; };
@@ -110,6 +113,7 @@
 			children = (
 				C0B74A2E2A8280D80018D10F /* Services.swift */,
 				BEEF9EC02A67C74E002126F4 /* PlacesService.swift */,
+				BE38A8892AA7294400EB5431 /* UserLocationService.swift */,
 			);
 			path = Services;
 			sourceTree = "<group>";
@@ -142,6 +146,7 @@
 		C05610472A5C78CA007FB970 /* DevAcademy */ = {
 			isa = PBXGroup;
 			children = (
+				BE38A8882AA7285B00EB5431 /* Info.plist */,
 				C05610482A5C78CA007FB970 /* DevAcademyApp.swift */,
 				C056104A2A5C78CA007FB970 /* RootView.swift */,
 				C0CAEAC42A801F3C008D87C2 /* Environment */,
@@ -266,6 +271,7 @@
 			buildActionMask = 2147483647;
 			files = (
 				849BA6402A79094500D8E0F0 /* PlaceDetailView.swift in Sources */,
+				BE38A88A2AA7294400EB5431 /* UserLocationService.swift in Sources */,
 				C0CAEAC12A8017E7008D87C2 /* MapView.swift in Sources */,
 				C0CAEAD12A8023FB008D87C2 /* PlacesObservableObject.swift in Sources */,
 				C0CAEABB2A8009A4008D87C2 /* PlacesViewState.swift in Sources */,
@@ -417,6 +423,7 @@
 				DEVELOPMENT_TEAM = "";
 				ENABLE_PREVIEWS = YES;
 				GENERATE_INFOPLIST_FILE = YES;
+				INFOPLIST_FILE = DevAcademy/Info.plist;
 				INFOPLIST_KEY_UIApplicationSceneManifest_Generation = YES;
 				INFOPLIST_KEY_UIApplicationSupportsIndirectInputEvents = YES;
 				INFOPLIST_KEY_UILaunchScreen_Generation = YES;
@@ -446,6 +453,7 @@
 				DEVELOPMENT_TEAM = "";
 				ENABLE_PREVIEWS = YES;
 				GENERATE_INFOPLIST_FILE = YES;
+				INFOPLIST_FILE = DevAcademy/Info.plist;
 				INFOPLIST_KEY_UIApplicationSceneManifest_Generation = YES;
 				INFOPLIST_KEY_UIApplicationSupportsIndirectInputEvents = YES;
 				INFOPLIST_KEY_UILaunchScreen_Generation = YES;

DevAcademy/Environment/ObservableObjects.swift

@@ -16,7 +16,7 @@ final class ObservableObjects {
 
 extension ObservableObjects {
     convenience init(services: Services) {
-        let places = PlacesObservableObject(placesService: services.placesService)
+        let places = PlacesObservableObject(placesService: services.placesService, locationService: services.locationService)
 
         self.init(
             places: places

DevAcademy/Environment/ObservableObjects/PlacesObservableObject.swift

@@ -1,4 +1,5 @@
 import Foundation
+import CoreLocation
 
 final class PlacesObservableObject: ObservableObject {
     @Published var places: [Place] = []
@@ -15,9 +16,29 @@ final class PlacesObservableObject: ObservableObject {
         didSet { updatePlaces() }
     }
     private let placesService: PlacesService
-
-    init(placesService: PlacesService) {
+    private let locationService: UserLocationService
+    private var lastUpdatedLocation: CLLocation?
+
+
+    init(placesService: PlacesService, locationService: UserLocationService) {
         self.placesService = placesService
+        self.locationService = locationService
+
+        self.locationService.listenDidUpdateLocation { [weak self] location in
+            DispatchQueue.main.async {
+                self?.locationDidUpdate(location: location)
+            }
+        }
+
+        self.locationService.listenDidUpdateStatus { [weak self] status in
+            switch status {
+            case .notDetermined:
+                self?.locationService.requestAuthorization()
+            case .authorizedWhenInUse, .authorizedAlways:
+                self?.beginLocationUpdates()
+            default: break
+            }
+        }
     }
 
     func set(place: Place, favourite setFavourite: Bool) {
@@ -76,6 +97,20 @@ final class PlacesObservableObject: ObservableObject {
 
     private func updatePlaces() {
         var regularPlaces = rawPlaces
+
+        if let lastUpdatedLocation {
+            regularPlaces.sort { lPlace, rPlace in
+                guard let rPoint = rPlace.geometry?.cllocation else {
+                    return false
+                }
+                guard let lPoint = lPlace.geometry?.cllocation else {
+                    return true
+                }
+
+                return lastUpdatedLocation.distance(from: lPoint).magnitude < lastUpdatedLocation.distance(from: rPoint).magnitude
+            }
+        }
+
         var presentOnTop: [Place] = []
         let favouritePlaces = self.favouritePlaces ?? []
 
@@ -90,4 +125,18 @@ final class PlacesObservableObject: ObservableObject {
 
         self.places = presentOnTop + regularPlaces
     }
+
+    private func shouldUpdate(location: CLLocation) -> Bool {
+        lastUpdatedLocation.flatMap { $0.distance(from: location).magnitude > 500 } ?? true
+    }
+
+    private func beginLocationUpdates() {
+        self.locationService.startUpdatingLocation()
+    }
+
+    private func locationDidUpdate(location: [CLLocation]) {
+        guard let userLocation = location.first, shouldUpdate(location: userLocation) else { return }
+        self.lastUpdatedLocation = userLocation
+        updatePlaces()
+    }
 }

DevAcademy/Info.plist

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>NSLocationWhenInUseUsageDescription</key>
+	<string>Najít nejbližší podnik</string>
+</dict>
+</plist>

DevAcademy/Model/Point.swift

@@ -1,3 +1,5 @@
+import CoreLocation
+
 struct Point: Decodable {
     var latitude: Double
     var longitude: Double
@@ -7,3 +9,9 @@ struct Point: Decodable {
         case longitude = "x"
     }
 }
+
+extension Point {
+    var cllocation: CLLocation {
+        .init(latitude: latitude, longitude: longitude)
+    }
+}

DevAcademy/Services/Services.swift

@@ -2,20 +2,25 @@ import Foundation
 
 final class Services {
     let placesService: PlacesService
+    let locationService: UserLocationService
 
     init(
-        placesService: PlacesService
+        placesService: PlacesService,
+        locationService: UserLocationService
     ) {
         self.placesService = placesService
+        self.locationService = locationService
     }
 }
 
 extension Services {
     convenience init() {
         let placesService = ProductionPlacesService()
+        let locationService = ProductionUserLocationService()
 
         self.init(
-            placesService: placesService
+            placesService: placesService,
+            locationService: locationService
         )
     }
 }
@@ -24,6 +29,7 @@ extension Services {
 
 extension Services {
     static let mock = Services(
-        placesService: MockPlacesService()
+        placesService: MockPlacesService(),
+        locationService: MockLocationService()
     )
 }

DevAcademy/Services/UserLocationService.swift

@@ -0,0 +1,63 @@
+import Combine
+import CoreLocation
+
+protocol UserLocationService {
+    func startUpdatingLocation()
+    func stopUpdatingLocation()
+    func requestAuthorization()
+
+    func listenDidUpdateLocation(handler: @escaping ([CLLocation]) -> Void)
+    func listenDidUpdateStatus(handler: @escaping (CLAuthorizationStatus) -> Void)
+}
+
+final class ProductionUserLocationService: NSObject, UserLocationService {
+
+    private let manager = CLLocationManager()
+    private var stateChangeHandler: ((CLAuthorizationStatus) -> Void)?
+    private var locationChangeHandler: (([CLLocation]) -> Void)?
+
+    override init() {
+        super.init()
+        manager.delegate = self
+    }
+
+    func requestAuthorization() {
+        manager.requestWhenInUseAuthorization()
+    }
+
+    func listenDidUpdateLocation(handler: @escaping ([CLLocation]) -> Void) {
+        self.locationChangeHandler = handler
+    }
+
+    func listenDidUpdateStatus(handler: @escaping (CLAuthorizationStatus) -> Void) {
+        self.stateChangeHandler = handler
+        handler(manager.authorizationStatus)
+    }
+
+    func stopUpdatingLocation() {
+        manager.stopUpdatingLocation()
+    }
+
+    func startUpdatingLocation() {
+        manager.startUpdatingLocation()
+    }
+
+}
+
+extension ProductionUserLocationService: CLLocationManagerDelegate {
+    func locationManagerDidChangeAuthorization(_ manager: CLLocationManager) {
+        self.stateChangeHandler?(manager.authorizationStatus)
+    }
+
+    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
+        self.locationChangeHandler?(locations)
+    }
+}
+
+final class MockLocationService: UserLocationService {
+    func startUpdatingLocation() { /* nop */ }
+    func stopUpdatingLocation() { /* nop */ }
+    func listenDidUpdateLocation(handler: @escaping ([CLLocation]) -> Void) { /* nop */ }
+    func requestAuthorization() { /* nop */ }
+    func listenDidUpdateStatus(handler: @escaping (CLAuthorizationStatus) -> Void) { /* nop */ }
+}

doc/l9assignment.md

@@ -0,0 +1,110 @@
+# Lekce 9: Zadání
+
+Lokační služby
+
+
+## Úkol 1: User Location Service
+Motivace: Potřebujeme vytvořit třídu, která bude zaobalovat komunikaci s API pro Polohové služby. Tato service musí mluvit s managerem pomocí patternu *delegate*, ale sama poskytuje API s closure.
+
+ 1. V adresáři `Services` vytvořme soubor `UserLocationService.swift` pro novou `UserLocationService`.
+ 2. Využijte template (viz níže)
+ 3. Tuto service přidejte na všechny nutná místa (viz předchozí lekce - přidání `PlaceService`)
+ 4. Tuto service přidejte do `PlacesObservableObjectu`.
+ 5. Implementujte jednotlivé funkce service: 
+ 	- Projděte si dokumentaci [CLLocationManager](https://developer.apple.com/documentation/corelocation/cllocationmanager) a implementujte následující funkce:
+ 	- Konstruktor vytvoří instanci CLLocationManager a uloží ji do proměnné `manager`. Nastavte delegáta na `self`.
+ 	- Funkce `requestAuthoriation` požádá manager o pravomoc získávat lokaci, pokud je aplikace **na popředí**.
+ 	- Funkce `listenDidUpdateLocation` nastaví novou closure pro naslouchání na změnu lokace
+ 	- Funkce `listenDidUpdateStatus` nastaví novou closure pro naslouchání na změnu stavu autorizace
+ 	- Funkce `stopUpdatingLocation` vypne získávání polohy
+ 	- Funkce `startUpdatingLocation` zapne získávání polohy
+ 	- Funkce v delegátu `locationManagerDidChangeAuthorization` do odpovídajícího handleru pošle nový stav autorizace
+ 	- Funkce v delegátu `locationManager(_:didUpdateLocations:)` do odpovídajícího handleru pošle aktuální polohu 
+
+## Úkol 2: Příprava na nasazení:
+Motivace: Před tím, než můžeme začít používat naše nové API si musíme ještě připravit nějaké věci.
+
+1. V souboru `Point.swift` vytvořte `extension` nad typem `Point`. Tato `extension` bude obsahovat *computed property* `var cllocation: CLLocation`, která z `Point` vytvoří `CLLocation`. (Budete muset importovat `CoreLocation`).
+2. iOS vyžaduje odůvodnění, proč chcete používat polohu. Toto odůvodnění **musí** být lokalizované a v Apple jej kontrolují! Otevřete soubor `Info.plist` a přidejte nový klíč `NSLocationWhenInUseUsageDescription` a odpovídající slovní popis.
+
+## Úkol 3: Implementace řazení podle polohy
+Motivace: Nyní můžeme implementovat ve třídě `PlacesObservableObject` řazení polohy.
+
+1. Přidejte novou proměnnou `private var lastUpdatedLocation: CLLocation?` - zde budete ukládat poslední bod, podle kterého byla místa seřazena.
+2. Do funkce `updatePlaces` přidejte novou funkcionalitu. Pokud je proměnná `lastUpdatedLocation ` ne-nil, seřaďte místa podle vzdálenosti. Použijte na pole `regularPlaces` funkci `sort`
+3. Přidejte funkci `beginLocationUpdates`, která zapne aktualizaci polohy na service.
+4. Přidejte funkci `func shouldUpdate(location: CLLocation) -> Bool`. Tato funkce vrátí `true`, pokud je **první prvek v poli** v argumentu `location` vzdálen od `lastUpdatedLocation` více, než je (vámi zvolená) vzdálenost. Pokud je `lastUpdatedLocation` nil, vrátí automaticky `true`.
+5. V konstruktoru Observable Objectu nastavte pro `locationService` handler `listenDidUpdateLocation`. Pokud funkce `self.shouldUpdate(location:)` vrátí `true`, aktualizujte `lastUpdatedLocation` a zavolejte `updatePlaces()`.
+6. V konstruktoru Observable Object nastavte pro `locationService` handler `listenDidUpdateStatus`. 
+  - Pokud je status `notDetermined`, zavolejte na `locationService` funkci `requestAuthorization()`
+  - Pokud je status `authorizedWhenInUse` nebo `authorizedAlways`, započněte získávání polohy
+  - Jinak nedělejte nic 
+
+
+---
+
+Template pro service
+
+```swift
+import Combine
+import CoreLocation
+
+protocol UserLocationService {    
+    func startUpdatingLocation()
+    func stopUpdatingLocation()
+    func requestAuthorization()
+
+    func listenDidUpdateLocation(handler: @escaping ([CLLocation]) -> Void)
+    func listenDidUpdateStatus(handler: @escaping (CLAuthorizationStatus) -> Void)
+}
+
+final class ProductionUserLocationService: NSObject, UserLocationService {
+
+    private let manager: CLLocationManager
+    private var stateChangeHandler: ((CLAuthorizationStatus) -> Void)?
+    private var locationChangeHandler: (([CLLocation]) -> Void)?
+
+    override init() {
+        // TODO
+    }
+
+    func requestAuthorization() {
+        // TODO
+    }
+
+    func listenDidUpdateLocation(handler: @escaping ([CLLocation]) -> Void) {
+        // TODO
+    }
+
+
+    func stopUpdatingLocation() {
+        // TODO
+    }
+
+    func startUpdatingLocation() {
+        // TODO
+    }
+
+    func listenDidUpdateStatus(handler: @escaping (CLAuthorizationStatus) -> Void) {
+        // TODO
+    }
+}
+
+extension ProductionUserLocationService: CLLocationManagerDelegate {
+    func locationManagerDidChangeAuthorization(_ manager: CLLocationManager) {
+        // TODO
+    }
+
+    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
+        // TODO
+    }
+}
+
+final class MockLocationService: UserLocationService {
+    func startUpdatingLocation() { /* nop */ }
+    func stopUpdatingLocation() { /* nop */ }
+    func listenDidUpdateLocation(handler: @escaping ([CLLocation]) -> Void) { /* nop */ }
+    func requestAuthorization() { /* nop */ }
+    func listenDidUpdateStatus(handler: @escaping (CLAuthorizationStatus) -> Void) { /* nop */ }
+}
+```