Memilih Lokasi Saat Ini dan Menampilkan Detail pada Peta

Tutorial ini menunjukkan cara mem-build aplikasi iOS yang mengambil lokasi perangkat saat ini, mengidentifikasi kemungkinan lokasi, meminta pengguna untuk memilih kecocokan terbaik, dan menampilkan penanda peta untuk lokasi yang dipilih.

Tutorial ini cocok untuk orang yang memiliki pengetahuan tingkat pemula atau menengah dalam Swift atau Objective-C dan pengetahuan umum tentang Xcode. Untuk panduan lanjutan cara membuat peta, baca panduan developer.

Anda akan membuat peta berikut menggunakan tutorial ini. Penanda peta diposisikan di San Francisco, California, tetapi akan berpindah ke mana pun perangkat atau simulator berada.

Tutorial ini menggunakan Places SDK for iOS, Maps SDK for iOS, dan framework Apple Core Location.

Mendapatkan kode

Atau, klik tombol berikut untuk mendownload kode sumber:

Beri saya kode

import UIKit
import GoogleMaps
import GooglePlaces

class MapViewController: UIViewController {

  var locationManager: CLLocationManager!
  var currentLocation: CLLocation?
  var mapView: GMSMapView!
  var placesClient: GMSPlacesClient!
  var preciseLocationZoomLevel: Float = 15.0
  var approximateLocationZoomLevel: Float = 10.0

  // An array to hold the list of likely places.
  var likelyPlaces: [GMSPlace] = []

  // The currently selected place.
  var selectedPlace: GMSPlace?

  // Update the map once the user has made their selection.
  @IBAction func unwindToMain(segue: UIStoryboardSegue) {
    // Clear the map.
    mapView.clear()

    // Add a marker to the map.
    if let place = selectedPlace {
      let marker = GMSMarker(position: place.coordinate)
      marker.title = selectedPlace?.name
      marker.snippet = selectedPlace?.formattedAddress
      marker.map = mapView
    }

    listLikelyPlaces()
  }

  override func viewDidLoad() {
    super.viewDidLoad()

    // Initialize the location manager.
    locationManager = CLLocationManager()
    locationManager.desiredAccuracy = kCLLocationAccuracyBest
    locationManager.requestWhenInUseAuthorization()
    locationManager.distanceFilter = 50
    locationManager.startUpdatingLocation()
    locationManager.delegate = self

    placesClient = GMSPlacesClient.shared()

    // A default location to use when location permission is not granted.
    let defaultLocation = CLLocation(latitude: -33.869405, longitude: 151.199)

    // Create a map.
    let zoomLevel = locationManager.accuracyAuthorization == .fullAccuracy ? preciseLocationZoomLevel : approximateLocationZoomLevel
    let camera = GMSCameraPosition.camera(withLatitude: defaultLocation.coordinate.latitude,
                                          longitude: defaultLocation.coordinate.longitude,
                                          zoom: zoomLevel)
    mapView = GMSMapView.map(withFrame: view.bounds, camera: camera)
    mapView.settings.myLocationButton = true
    mapView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
    mapView.isMyLocationEnabled = true

    // Add the map to the view, hide it until we've got a location update.
    view.addSubview(mapView)
    mapView.isHidden = true

    listLikelyPlaces()
  }

  // Populate the array with the list of likely places.
  func listLikelyPlaces() {
    // Clean up from previous sessions.
    likelyPlaces.removeAll()

    let placeFields: GMSPlaceField = [.name, .coordinate]
    placesClient.findPlaceLikelihoodsFromCurrentLocation(withPlaceFields: placeFields) { (placeLikelihoods, error) in
      guard error == nil else {
        // TODO: Handle the error.
        print("Current Place error: \(error!.localizedDescription)")
        return
      }

      guard let placeLikelihoods = placeLikelihoods else {
        print("No places found.")
        return
      }

      // Get likely places and add to the list.
      for likelihood in placeLikelihoods {
        let place = likelihood.place
        self.likelyPlaces.append(place)
      }
    }
  }

  // Prepare the segue.
  override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "segueToSelect" {
      if let nextViewController = segue.destination as? PlacesViewController {
        nextViewController.likelyPlaces = likelyPlaces
      }
    }
  }
}

// Delegates to handle events for the location manager.
extension MapViewController: CLLocationManagerDelegate {

  // Handle incoming location events.
  func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    let location: CLLocation = locations.last!
    print("Location: \(location)")

    let zoomLevel = locationManager.accuracyAuthorization == .fullAccuracy ? preciseLocationZoomLevel : approximateLocationZoomLevel
    let camera = GMSCameraPosition.camera(withLatitude: location.coordinate.latitude,
                                          longitude: location.coordinate.longitude,
                                          zoom: zoomLevel)

    if mapView.isHidden {
      mapView.isHidden = false
      mapView.camera = camera
    } else {
      mapView.animate(to: camera)
    }

    listLikelyPlaces()
  }

  // Handle authorization for the location manager.
  func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
    // Check accuracy authorization
    let accuracy = manager.accuracyAuthorization
    switch accuracy {
    case .fullAccuracy:
        print("Location accuracy is precise.")
    case .reducedAccuracy:
        print("Location accuracy is not precise.")
    @unknown default:
      fatalError()
    }

    // Handle authorization status
    switch status {
    case .restricted:
      print("Location access was restricted.")
    case .denied:
      print("User denied access to location.")
      // Display the map using the default location.
      mapView.isHidden = false
    case .notDetermined:
      print("Location status not determined.")
    case .authorizedAlways: fallthrough
    case .authorizedWhenInUse:
      print("Location status is OK.")
    @unknown default:
      fatalError()
    }
  }

  // Handle location manager errors.
  func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
    locationManager.stopUpdatingLocation()
    print("Error: \(error)")
  }
}
      

#import "MapViewController.h"
#import "PlacesViewController.h"
@import CoreLocation;
@import GooglePlaces;
@import GoogleMaps;

@interface MapViewController () <CLLocationManagerDelegate>

@end

@implementation MapViewController {
  CLLocationManager *locationManager;
  CLLocation * _Nullable currentLocation;
  GMSMapView *mapView;
  GMSPlacesClient *placesClient;
  float preciseLocationZoomLevel;
  float approximateLocationZoomLevel;

  // An array to hold the list of likely places.
  NSMutableArray<GMSPlace *> *likelyPlaces;

  // The currently selected place.
  GMSPlace * _Nullable selectedPlace;
}

- (void)viewDidLoad {
  [super viewDidLoad];
  preciseLocationZoomLevel = 15.0;
  approximateLocationZoomLevel = 15.0;

  // Initialize the location manager.
  locationManager = [[CLLocationManager alloc] init];
  locationManager.desiredAccuracy = kCLLocationAccuracyBest;
  [locationManager requestWhenInUseAuthorization];
  locationManager.distanceFilter = 50;
  [locationManager startUpdatingLocation];
  locationManager.delegate = self;

  placesClient = [GMSPlacesClient sharedClient];

  // A default location to use when location permission is not granted.
  CLLocationCoordinate2D defaultLocation = CLLocationCoordinate2DMake(-33.869405, 151.199);

  // Create a map.
  float zoomLevel = locationManager.accuracyAuthorization == CLAccuracyAuthorizationFullAccuracy ? preciseLocationZoomLevel : approximateLocationZoomLevel;
  GMSCameraPosition *camera = [GMSCameraPosition cameraWithLatitude:defaultLocation.latitude
                                                          longitude:defaultLocation.longitude
                                                               zoom:zoomLevel];
  mapView = [GMSMapView mapWithFrame:self.view.bounds camera:camera];
  mapView.settings.myLocationButton = YES;
  mapView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
  mapView.myLocationEnabled = YES;

  // Add the map to the view, hide it until we've got a location update.
  [self.view addSubview:mapView];
  mapView.hidden = YES;

  [self listLikelyPlaces];
}

// Populate the array with the list of likely places.
- (void) listLikelyPlaces
{
  // Clean up from previous sessions.
  likelyPlaces = [NSMutableArray array];

  GMSPlaceField placeFields = GMSPlaceFieldName | GMSPlaceFieldCoordinate;
  [placesClient findPlaceLikelihoodsFromCurrentLocationWithPlaceFields:placeFields callback:^(NSArray<GMSPlaceLikelihood *> * _Nullable likelihoods, NSError * _Nullable error) {
    if (error != nil) {
      // TODO: Handle the error.
      NSLog(@"Current Place error: %@", error.localizedDescription);
      return;
    }

    if (likelihoods == nil) {
      NSLog(@"No places found.");
      return;
    }

    for (GMSPlaceLikelihood *likelihood in likelihoods) {
      GMSPlace *place = likelihood.place;
      [likelyPlaces addObject:place];
    }
  }];
}

// Update the map once the user has made their selection.
- (void) unwindToMain:(UIStoryboardSegue *)segue
{
  // Clear the map.
  [mapView clear];

  // Add a marker to the map.
  if (selectedPlace != nil) {
    GMSMarker *marker = [GMSMarker markerWithPosition:selectedPlace.coordinate];
    marker.title = selectedPlace.name;
    marker.snippet = selectedPlace.formattedAddress;
    marker.map = mapView;
  }

  [self listLikelyPlaces];
}

// Prepare the segue.
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
  if ([segue.identifier isEqualToString:@"segueToSelect"]) {
    if ([segue.destinationViewController isKindOfClass:[PlacesViewController class]]) {
      PlacesViewController *placesViewController = (PlacesViewController *)segue.destinationViewController;
      placesViewController.likelyPlaces = likelyPlaces;
    }
  }
}

// Delegates to handle events for the location manager.
#pragma mark - CLLocationManagerDelegate

// Handle incoming location events.
- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray<CLLocation *> *)locations
{
  CLLocation *location = locations.lastObject;
  NSLog(@"Location: %@", location);

  float zoomLevel = locationManager.accuracyAuthorization == CLAccuracyAuthorizationFullAccuracy ? preciseLocationZoomLevel : approximateLocationZoomLevel;
  GMSCameraPosition * camera = [GMSCameraPosition cameraWithLatitude:location.coordinate.latitude
                                                           longitude:location.coordinate.longitude
                                                                zoom:zoomLevel];

  if (mapView.isHidden) {
    mapView.hidden = NO;
    mapView.camera = camera;
  } else {
    [mapView animateToCameraPosition:camera];
  }

  [self listLikelyPlaces];
}

// Handle authorization for the location manager.
- (void)locationManager:(CLLocationManager *)manager didChangeAuthorizationStatus:(CLAuthorizationStatus)status
{
  // Check accuracy authorization
  CLAccuracyAuthorization accuracy = manager.accuracyAuthorization;
  switch (accuracy) {
    case CLAccuracyAuthorizationFullAccuracy:
      NSLog(@"Location accuracy is precise.");
      break;
    case CLAccuracyAuthorizationReducedAccuracy:
      NSLog(@"Location accuracy is not precise.");
      break;
  }

  // Handle authorization status
  switch (status) {
    case kCLAuthorizationStatusRestricted:
      NSLog(@"Location access was restricted.");
      break;
    case kCLAuthorizationStatusDenied:
      NSLog(@"User denied access to location.");
      // Display the map using the default location.
      mapView.hidden = NO;
    case kCLAuthorizationStatusNotDetermined:
      NSLog(@"Location status not determined.");
    case kCLAuthorizationStatusAuthorizedAlways:
    case kCLAuthorizationStatusAuthorizedWhenInUse:
      NSLog(@"Location status is OK.");
  }
}

// Handle location manager errors.
- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error
{
  [manager stopUpdatingLocation];
  NSLog(@"Error: %@", error.localizedDescription);
}

@end
      

import UIKit
import GooglePlaces

class PlacesViewController: UIViewController {

  // ...

  // Pass the selected place to the new view controller.
  override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "unwindToMain" {
      if let nextViewController = segue.destination as? MapViewController {
        nextViewController.selectedPlace = selectedPlace
      }
    }
  }
}

// Respond when a user selects a place.
extension PlacesViewController: UITableViewDelegate {
  func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    selectedPlace = likelyPlaces[indexPath.row]
    performSegue(withIdentifier: "unwindToMain", sender: self)
  }

  // Adjust cell height to only show the first five items in the table
  // (scrolling is disabled in IB).
  func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
    return self.tableView.frame.size.height/5
  }

  // Make table rows display at proper height if there are less than 5 items.
  func tableView(_ tableView: UITableView, heightForFooterInSection section: Int) -> CGFloat {
    if (section == tableView.numberOfSections - 1) {
      return 1
    }
    return 0
  }
}

// Populate the table with the list of most likely places.
extension PlacesViewController: UITableViewDataSource {
  func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return likelyPlaces.count
  }

  func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(withIdentifier: cellReuseIdentifier, for: indexPath)
    let collectionItem = likelyPlaces[indexPath.row]

    cell.textLabel?.text = collectionItem.name

    return cell
  }
}
      

#import "PlacesViewController.h"

@interface PlacesViewController () <UITableViewDataSource, UITableViewDelegate>
// ...

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{

}

#pragma mark - UITableViewDelegate

// Respond when a user selects a place.
-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
  self.selectedPlace = [self.likelyPlaces objectAtIndex:indexPath.row];
  [self performSegueWithIdentifier:@"unwindToMain" sender:self];
}

// Adjust cell height to only show the first five items in the table
// (scrolling is disabled in IB).
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
  return self.tableView.frame.size.height/5;
}

// Make table rows display at proper height if there are less than 5 items.
-(CGFloat)tableView:(UITableView *)tableView heightForFooterInSection:(NSInteger)section
{
  if (section == tableView.numberOfSections - 1) {
    return 1;
  }
  return 0;
}

#pragma mark - UITableViewDataSource

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
  return self.likelyPlaces.count;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
  return [tableView dequeueReusableCellWithIdentifier:cellReuseIdentifier forIndexPath:indexPath];
}
@end
      

Mulai

Mendapatkan kunci API dan mengaktifkan API yang diperlukan

Untuk menyelesaikan tutorial ini, Anda memerlukan kunci Google API yang diizinkan untuk menggunakan Maps SDK for iOS dan Places API.

1. Ikuti petunjuk di Memulai Google Maps Platform untuk menyiapkan akun penagihan dan project yang diaktifkan dengan kedua produk ini.
2. Ikuti petunjuk di Mendapatkan Kunci API untuk membuat kunci API bagi project pengembangan yang Anda siapkan sebelumnya.

Menambahkan kunci API ke aplikasi

Tambahkan kunci API ke AppDelegate.swift sebagai berikut:

1. Perhatikan bahwa pernyataan impor berikut telah ditambahkan ke file tersebut:

   import GooglePlaces
   import GoogleMaps

2. Edit baris berikut dalam metode application(_:didFinishLaunchingWithOptions:) Anda, yang menggantikan YOUR_API_KEY dengan kunci API Anda:

   GMSPlacesClient.provideAPIKey("YOUR_API_KEY")
   GMSServices.provideAPIKey("YOUR_API_KEY")

Membuat dan menjalankan aplikasi

1. Hubungkan perangkat iOS ke komputer, atau pilih simulator dari menu pop-up skema Xcode.
2. Jika Anda menggunakan perangkat, pastikan layanan lokasi telah diaktifkan. Jika Anda menggunakan simulator, pilih lokasi dari menu Fitur.
3. Di Xcode, klik opsi menu Product/Run (atau ikon tombol putar).
• Xcode akan mem-build aplikasi, lalu menjalankan aplikasi tersebut di perangkat atau di simulator.
• Anda akan melihat peta dengan sejumlah penanda yang dipusatkan di sekitar lokasi Anda saat ini.

Pemecahan masalah:

• Jika Anda tidak melihat peta, pastikan bahwa Anda telah mendapatkan kunci API dan menambahkannya ke aplikasi, seperti yang dijelaskan di atas. Periksa konsol proses debug Xcode untuk melihat pesan error tentang kunci API.
• Jika Anda telah membatasi kunci API berdasarkan ID paket iOS, edit kunci untuk menambahkan ID paket tersebut untuk aplikasi: com.google.examples.current-place-on-map.
• Peta tidak akan menampilkan dengan benar jika permintaan izin untuk layanan lokasi ditolak.
  • Jika Anda menggunakan perangkat, buka Setelan/Umum/Privasi/Layanan Lokasi, lalu aktifkan kembali layanan lokasi.
  • Jika Anda menggunakan simulator, buka Simulator/Reset Content and Settings...
  Saat berikutnya aplikasi dijalankan, pastikan menerima konfirmasi layanan lokasi.
• Pastikan Anda memiliki koneksi WiFi atau GPS yang baik.
• Jika aplikasi diluncurkan, tetapi peta tidak ditampilkan, pastikan Anda telah memperbarui Info.plist untuk project Anda dengan izin lokasi yang sesuai. Untuk informasi selengkapnya tentang penanganan izin, lihat panduan untuk meminta izin akses lokasi di aplikasi Anda di bawah.
• Gunakan alat debug Xcode untuk melihat log dan men-debug aplikasi.

Memahami kode

Bagian tutorial ini menjelaskan bagian yang paling signifikan dari aplikasi current-place-on-map, untuk membantu Anda memahami cara mem-build aplikasi serupa.

Aplikasi current-place-on-map menampilkan dua pengontrol tampilan: Satu untuk menampilkan peta yang menunjukkan tempat yang saat ini dipilih pengguna, dan satu lagi untuk menampilkan daftar kemungkinan tempat yang dapat dipilih pengguna. Perhatikan bahwa setiap pengontrol tampilan memiliki variabel yang sama untuk melacak daftar tempat yang mungkin (likelyPlaces), dan untuk menunjukkan pemilihan pengguna (selectedPlace). Navigasi antar-tampilan dilakukan dengan menggunakan transisi.

Meminta izin akses lokasi

Aplikasi Anda harus mengonfirmasikan persetujuan pengguna untuk menggunakan layanan lokasi. Untuk melakukannya, sertakan kunci NSLocationAlwaysUsageDescription dalam file Info.plist untuk aplikasi, dan tetapkan nilai setiap kunci ke string yang menjelaskan maksud aplikasi untuk menggunakan data lokasi.

Menyiapkan pengelola lokasi

Gunakan CLLocationManager untuk menemukan lokasi perangkat saat ini dan meminta pembaruan rutin saat perangkat berpindah ke lokasi baru. Tutorial ini menyediakan kode yang Anda butuhkan untuk mendapatkan lokasi perangkat. Untuk mengetahui detail selengkapnya, lihat panduan untuk Mendapatkan Lokasi Pengguna di Dokumentasi Developer Apple.

1. Deklarasikan pengelola lokasi, lokasi saat ini, tampilan peta, klien tempat, dan tingkat zoom default pada tingkat class.

Swift

var locationManager: CLLocationManager!
var currentLocation: CLLocation?
var mapView: GMSMapView!
var placesClient: GMSPlacesClient!
var preciseLocationZoomLevel: Float = 15.0
var approximateLocationZoomLevel: Float = 10.0
      

Objective-C

CLLocationManager *locationManager;
CLLocation * _Nullable currentLocation;
GMSMapView *mapView;
GMSPlacesClient *placesClient;
float preciseLocationZoomLevel;
float approximateLocationZoomLevel;
      

2. Lakukan inisialisasi pengelola lokasi dan GMSPlacesClient di viewDidLoad().

Swift

// Initialize the location manager.
locationManager = CLLocationManager()
locationManager.desiredAccuracy = kCLLocationAccuracyBest
locationManager.requestWhenInUseAuthorization()
locationManager.distanceFilter = 50
locationManager.startUpdatingLocation()
locationManager.delegate = self

placesClient = GMSPlacesClient.shared()
      

Objective-C

// Initialize the location manager.
locationManager = [[CLLocationManager alloc] init];
locationManager.desiredAccuracy = kCLLocationAccuracyBest;
[locationManager requestWhenInUseAuthorization];
locationManager.distanceFilter = 50;
[locationManager startUpdatingLocation];
locationManager.delegate = self;

placesClient = [GMSPlacesClient sharedClient];
      

3. Deklarasikan variabel untuk menyimpan daftar kemungkinan tempat, dan tempat yang dipilih pengguna.

Swift

// An array to hold the list of likely places.
var likelyPlaces: [GMSPlace] = []

// The currently selected place.
var selectedPlace: GMSPlace?
      

Objective-C

// An array to hold the list of likely places.
NSMutableArray<GMSPlace *> *likelyPlaces;

// The currently selected place.
GMSPlace * _Nullable selectedPlace;
      

4. Tambahkan delegasi untuk menangani peristiwa bagi pengelola lokasi, menggunakan klausa ekstensi.

Swift

// Delegates to handle events for the location manager.
extension MapViewController: CLLocationManagerDelegate {

  // Handle incoming location events.
  func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    let location: CLLocation = locations.last!
    print("Location: \(location)")

    let zoomLevel = locationManager.accuracyAuthorization == .fullAccuracy ? preciseLocationZoomLevel : approximateLocationZoomLevel
    let camera = GMSCameraPosition.camera(withLatitude: location.coordinate.latitude,
                                          longitude: location.coordinate.longitude,
                                          zoom: zoomLevel)

    if mapView.isHidden {
      mapView.isHidden = false
      mapView.camera = camera
    } else {
      mapView.animate(to: camera)
    }

    listLikelyPlaces()
  }

  // Handle authorization for the location manager.
  func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
    // Check accuracy authorization
    let accuracy = manager.accuracyAuthorization
    switch accuracy {
    case .fullAccuracy:
        print("Location accuracy is precise.")
    case .reducedAccuracy:
        print("Location accuracy is not precise.")
    @unknown default:
      fatalError()
    }

    // Handle authorization status
    switch status {
    case .restricted:
      print("Location access was restricted.")
    case .denied:
      print("User denied access to location.")
      // Display the map using the default location.
      mapView.isHidden = false
    case .notDetermined:
      print("Location status not determined.")
    case .authorizedAlways: fallthrough
    case .authorizedWhenInUse:
      print("Location status is OK.")
    @unknown default:
      fatalError()
    }
  }

  // Handle location manager errors.
  func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
    locationManager.stopUpdatingLocation()
    print("Error: \(error)")
  }
}
      

Objective-C

// Delegates to handle events for the location manager.
#pragma mark - CLLocationManagerDelegate

// Handle incoming location events.
- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray<CLLocation *> *)locations
{
  CLLocation *location = locations.lastObject;
  NSLog(@"Location: %@", location);

  float zoomLevel = locationManager.accuracyAuthorization == CLAccuracyAuthorizationFullAccuracy ? preciseLocationZoomLevel : approximateLocationZoomLevel;
  GMSCameraPosition * camera = [GMSCameraPosition cameraWithLatitude:location.coordinate.latitude
                                                           longitude:location.coordinate.longitude
                                                                zoom:zoomLevel];

  if (mapView.isHidden) {
    mapView.hidden = NO;
    mapView.camera = camera;
  } else {
    [mapView animateToCameraPosition:camera];
  }

  [self listLikelyPlaces];
}

// Handle authorization for the location manager.
- (void)locationManager:(CLLocationManager *)manager didChangeAuthorizationStatus:(CLAuthorizationStatus)status
{
  // Check accuracy authorization
  CLAccuracyAuthorization accuracy = manager.accuracyAuthorization;
  switch (accuracy) {
    case CLAccuracyAuthorizationFullAccuracy:
      NSLog(@"Location accuracy is precise.");
      break;
    case CLAccuracyAuthorizationReducedAccuracy:
      NSLog(@"Location accuracy is not precise.");
      break;
  }

  // Handle authorization status
  switch (status) {
    case kCLAuthorizationStatusRestricted:
      NSLog(@"Location access was restricted.");
      break;
    case kCLAuthorizationStatusDenied:
      NSLog(@"User denied access to location.");
      // Display the map using the default location.
      mapView.hidden = NO;
    case kCLAuthorizationStatusNotDetermined:
      NSLog(@"Location status not determined.");
    case kCLAuthorizationStatusAuthorizedAlways:
    case kCLAuthorizationStatusAuthorizedWhenInUse:
      NSLog(@"Location status is OK.");
  }
}

// Handle location manager errors.
- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error
{
  [manager stopUpdatingLocation];
  NSLog(@"Error: %@", error.localizedDescription);
}
      

Menambahkan peta

Buat peta dan tambahkan ke tampilan di viewDidLoad() di pengontrol tampilan utama. Peta tetap disembunyikan hingga pembaruan lokasi diterima (pembaruan lokasi ditangani di ekstensi CLLocationManagerDelegate).

// A default location to use when location permission is not granted.
let defaultLocation = CLLocation(latitude: -33.869405, longitude: 151.199)

// Create a map.
let zoomLevel = locationManager.accuracyAuthorization == .fullAccuracy ? preciseLocationZoomLevel : approximateLocationZoomLevel
let camera = GMSCameraPosition.camera(withLatitude: defaultLocation.coordinate.latitude,
                                      longitude: defaultLocation.coordinate.longitude,
                                      zoom: zoomLevel)
mapView = GMSMapView.map(withFrame: view.bounds, camera: camera)
mapView.settings.myLocationButton = true
mapView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
mapView.isMyLocationEnabled = true

// Add the map to the view, hide it until we've got a location update.
view.addSubview(mapView)
mapView.isHidden = true
      

// A default location to use when location permission is not granted.
CLLocationCoordinate2D defaultLocation = CLLocationCoordinate2DMake(-33.869405, 151.199);

// Create a map.
float zoomLevel = locationManager.accuracyAuthorization == CLAccuracyAuthorizationFullAccuracy ? preciseLocationZoomLevel : approximateLocationZoomLevel;
GMSCameraPosition *camera = [GMSCameraPosition cameraWithLatitude:defaultLocation.latitude
                                                        longitude:defaultLocation.longitude
                                                             zoom:zoomLevel];
mapView = [GMSMapView mapWithFrame:self.view.bounds camera:camera];
mapView.settings.myLocationButton = YES;
mapView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
mapView.myLocationEnabled = YES;

// Add the map to the view, hide it until we've got a location update.
[self.view addSubview:mapView];
mapView.hidden = YES;
      

Meminta pengguna untuk memilih tempat mereka saat ini

Gunakan Places SDK for iOS untuk mendapatkan lima kemungkinan tempat teratas berdasarkan lokasi pengguna saat ini, dan tampilkan daftar dalam UITableView. Saat pengguna memilih tempat, tambahkan penanda ke peta.

1. Dapatkan daftar kemungkinan tempat untuk mengisi UITableView, tempat pengguna dapat memilih tempat yang saat ini mereka tempati.

Swift

// Populate the array with the list of likely places.
func listLikelyPlaces() {
  // Clean up from previous sessions.
  likelyPlaces.removeAll()

  let placeFields: GMSPlaceField = [.name, .coordinate]
  placesClient.findPlaceLikelihoodsFromCurrentLocation(withPlaceFields: placeFields) { (placeLikelihoods, error) in
    guard error == nil else {
      // TODO: Handle the error.
      print("Current Place error: \(error!.localizedDescription)")
      return
    }

    guard let placeLikelihoods = placeLikelihoods else {
      print("No places found.")
      return
    }

    // Get likely places and add to the list.
    for likelihood in placeLikelihoods {
      let place = likelihood.place
      self.likelyPlaces.append(place)
    }
  }
}
      

Objective-C

// Populate the array with the list of likely places.
- (void) listLikelyPlaces
{
  // Clean up from previous sessions.
  likelyPlaces = [NSMutableArray array];

  GMSPlaceField placeFields = GMSPlaceFieldName | GMSPlaceFieldCoordinate;
  [placesClient findPlaceLikelihoodsFromCurrentLocationWithPlaceFields:placeFields callback:^(NSArray<GMSPlaceLikelihood *> * _Nullable likelihoods, NSError * _Nullable error) {
    if (error != nil) {
      // TODO: Handle the error.
      NSLog(@"Current Place error: %@", error.localizedDescription);
      return;
    }

    if (likelihoods == nil) {
      NSLog(@"No places found.");
      return;
    }

    for (GMSPlaceLikelihood *likelihood in likelihoods) {
      GMSPlace *place = likelihood.place;
      [likelyPlaces addObject:place];
    }
  }];
}
      

2. Buka tampilan baru untuk menampilkan kemungkinan tempat kepada pengguna. Saat pengguna mengetuk "Dapatkan Tempat", kita akan beralih ke tampilan baru, dan menampilkan daftar kemungkinan tempat yang dapat dipilih kepada pengguna. Fungsi prepare memperbarui PlacesViewController dengan daftar kemungkinan tempat saat ini, dan otomatis dipanggil saat segue dilakukan.

Swift

// Prepare the segue.
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
  if segue.identifier == "segueToSelect" {
    if let nextViewController = segue.destination as? PlacesViewController {
      nextViewController.likelyPlaces = likelyPlaces
    }
  }
}
      

Objective-C

// Prepare the segue.
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
  if ([segue.identifier isEqualToString:@"segueToSelect"]) {
    if ([segue.destinationViewController isKindOfClass:[PlacesViewController class]]) {
      PlacesViewController *placesViewController = (PlacesViewController *)segue.destinationViewController;
      placesViewController.likelyPlaces = likelyPlaces;
    }
  }
}
      

3. Di PlacesViewController, isi tabel menggunakan daftar tempat yang paling mungkin, menggunakan ekstensi delegasi UITableViewDataSource.

Swift

// Populate the table with the list of most likely places.
extension PlacesViewController: UITableViewDataSource {
  func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return likelyPlaces.count
  }

  func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(withIdentifier: cellReuseIdentifier, for: indexPath)
    let collectionItem = likelyPlaces[indexPath.row]

    cell.textLabel?.text = collectionItem.name

    return cell
  }
}
      

Objective-C

#pragma mark - UITableViewDataSource

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
  return self.likelyPlaces.count;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
  return [tableView dequeueReusableCellWithIdentifier:cellReuseIdentifier forIndexPath:indexPath];
}
@end
      

4. Tangani pilihan pengguna menggunakan ekstensi delegate UITableViewDelegate.

Swift

class PlacesViewController: UIViewController {

  // ...

  // Pass the selected place to the new view controller.
  override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "unwindToMain" {
      if let nextViewController = segue.destination as? MapViewController {
        nextViewController.selectedPlace = selectedPlace
      }
    }
  }
}

// Respond when a user selects a place.
extension PlacesViewController: UITableViewDelegate {
  func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    selectedPlace = likelyPlaces[indexPath.row]
    performSegue(withIdentifier: "unwindToMain", sender: self)
  }

  // Adjust cell height to only show the first five items in the table
  // (scrolling is disabled in IB).
  func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
    return self.tableView.frame.size.height/5
  }

  // Make table rows display at proper height if there are less than 5 items.
  func tableView(_ tableView: UITableView, heightForFooterInSection section: Int) -> CGFloat {
    if (section == tableView.numberOfSections - 1) {
      return 1
    }
    return 0
  }
}
      

Objective-C

@interface PlacesViewController () <UITableViewDataSource, UITableViewDelegate>
// ...

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{

}

#pragma mark - UITableViewDelegate

// Respond when a user selects a place.
-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
  self.selectedPlace = [self.likelyPlaces objectAtIndex:indexPath.row];
  [self performSegueWithIdentifier:@"unwindToMain" sender:self];
}

// Adjust cell height to only show the first five items in the table
// (scrolling is disabled in IB).
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
  return self.tableView.frame.size.height/5;
}

// Make table rows display at proper height if there are less than 5 items.
-(CGFloat)tableView:(UITableView *)tableView heightForFooterInSection:(NSInteger)section
{
  if (section == tableView.numberOfSections - 1) {
    return 1;
  }
  return 0;
}
      

Menambahkan penanda ke peta

Saat pengguna membuat pilihan, gunakan segue unwind untuk kembali ke tampilan sebelumnya, dan tambahkan penanda ke peta. unwindToMain ActionBar dipanggil secara otomatis setelah kembali ke pengontrol tampilan utama.

// Update the map once the user has made their selection.
@IBAction func unwindToMain(segue: UIStoryboardSegue) {
  // Clear the map.
  mapView.clear()

  // Add a marker to the map.
  if let place = selectedPlace {
    let marker = GMSMarker(position: place.coordinate)
    marker.title = selectedPlace?.name
    marker.snippet = selectedPlace?.formattedAddress
    marker.map = mapView
  }

  listLikelyPlaces()
}
      

// Update the map once the user has made their selection.
- (void) unwindToMain:(UIStoryboardSegue *)segue
{
  // Clear the map.
  [mapView clear];

  // Add a marker to the map.
  if (selectedPlace != nil) {
    GMSMarker *marker = [GMSMarker markerWithPosition:selectedPlace.coordinate];
    marker.title = selectedPlace.name;
    marker.snippet = selectedPlace.formattedAddress;
    marker.map = mapView;
  }

  [self listLikelyPlaces];
}
      

Selamat! Anda telah membuat aplikasi iOS yang memungkinkan pengguna memilih tempat mereka saat ini, dan menampilkan hasilnya di peta Google. Dalam proses melakukannya, Anda telah mempelajari cara menggunakan Places SDK for iOS, Maps SDK for iOS, dan framework Apple Core Location.