Learn how to display the current device location on a map A map is a collection of layers that are displayed in 2D. It is typically composed of a basemap layer and data layers. Learn more or scene A scene is a collection of layers that are displayed in 3D. It is typically composed of a basemap layer, data layers, and 3D data. Learn more .

display device location

You can display the device location on a map or scene. This is important for workflows that require the user’s current location, such as finding nearby businesses, navigating from the current location, or identifying and collecting geospatial information.

By default, location display uses the device’s location provider. Your app can also process input from other location providers, such as an external GPS receiver or a provider that returns a simulated location. For more information, see the Show device location topic.

Prerequisites

Before starting this tutorial:

  1. You need an ArcGIS Location Platform or ArcGIS Online account.

  2. Your system meets the system requirements.

Develop or Download

You have two options for completing this tutorial:

  1. Option 1: Develop the code or
  2. Option 2: Download the completed solution

Option 1: Develop the code

To start the tutorial, complete the Display a map tutorial. This creates a map to display the Santa Monica Mountains in California using the topographic basemap from the ArcGIS Basemap Styles service The ArcGIS Basemap Styles service, also referred to as the Basemap Styles service, is a location service that provides basemap styles and data for the world. It returns styles as Mapbox styles and web maps, and data as vector tiles and/or map tiles. It supports all of the styles in the ArcGIS Basemap style and Open Basemap style family. An ArcGIS Location Platform or ArcGIS Online account is required to use the service. Learn more .

Open an Xcode project

  1. Open the .xcodeproj project you created by completing the Display a map tutorial.
  2. Continue with the following instructions to display the current device location on a map or scene.

Add a custom iOS target property

The app must provide a message that tells the user why the app is requesting access to the user’s location when the app is in use.

  1. In Xcode, in the Project navigator, select the target app.

  2. Click the Info tab and add the “Privacy - Location When In Use Usage Description” key under Custom iOS Target Properties.

  3. Add a string value describing how the app would use the device location. For example, “Your location is used to show your position on the map.”

Import Core Location

  1. In Xcode, in the Project Navigator, click ContentView.swift.

  2. In the Editor, import the CoreLocation framework. This is required to request the user’s location.

    ContentView.swift
    import ArcGIS
    import CoreLocation

Initialize the map

  1. The map will zoom to the extent An extent is a bounding rectangle with points that delineate an area for a map or scene. Learn more of the current location, so you don’t need to set the viewpoint anymore. Remove the map StateObject and replace it with just a map initializer.

    ContentView.swift
    struct ContentView: View {
    private let map = Map(basemapStyle: .arcGISTopographic)

Add location display to map view

  1. Create the location display using the system location data source.

    ContentView.swift
    struct ContentView: View {
    private let map = Map(basemapStyle: .arcGISTopographic)
    private let locationDisplay = LocationDisplay(dataSource: SystemLocationDataSource())
  2. Add the location display modifier to the map view.

    ContentView.swift
    var body: some View {
    MapView(map: map)
    .locationDisplay(locationDisplay)
    }
    }

Request user authorization to use location

The app must request authorization from the user to access the device location. The user can grant or deny the request.

  1. In the task modifier, create a CLLocationManager.

  2. If the authorization status is not determined, request “in use authorization”.

    ContentView.swift
    var body: some View {
    MapView(map: map)
    .locationDisplay(locationDisplay)
    .task {
    let locationManager = CLLocationManager()
    if locationManager.authorizationStatus == .notDetermined {
    locationManager.requestWhenInUseAuthorization()
    }
    }
    }

Show the current location

A map view A map view is a user interface that displays map layers and graphics in 2D. It controls the area (extent) of the map that is visible and supports user interactions such as pan and zoom. Learn more provides LocationDisplay for showing the current location of the device A device is nearly any kind of computer, including desktops, laptops, mobile phones, and tablets. Learn more . The location symbol is displayed on top of all content in the map view.

  1. Start displaying the location by calling the data source’s start() method.

    ContentView.swift
    var body: some View {
    MapView(map: map)
    .locationDisplay(locationDisplay)
    .task {
    let locationManager = CLLocationManager()
    if locationManager.authorizationStatus == .notDetermined {
    locationManager.requestWhenInUseAuthorization()
    }
    do {
    try await locationDisplay.dataSource.start()
    } catch {
    }
    }
    }
  2. Set the initial zoom scale and the auto pan mode.

    ContentView.swift
    var body: some View {
    MapView(map: map)
    .locationDisplay(locationDisplay)
    .task {
    let locationManager = CLLocationManager()
    if locationManager.authorizationStatus == .notDetermined {
    locationManager.requestWhenInUseAuthorization()
    }
    do {
    try await locationDisplay.dataSource.start()
    locationDisplay.initialZoomScale = 40_000
    locationDisplay.autoPanMode = .recenter
    } catch {
    }
    }
    }

Error handling

  1. Add a Bool called failedToStart.

    ContentView.swift
    struct ContentView: View {
    private let map = Map(basemapStyle: .arcGISTopographic)
    private let locationDisplay = LocationDisplay(dataSource: SystemLocationDataSource())
    @State private var failedToStart = false
  2. In the catch closure, set the failedToStart boolean to true. If the location display fails to start, the value will be changed.

    ContentView.swift
    do {
    try await locationDisplay.dataSource.start()
    locationDisplay.initialZoomScale = 40_000
    locationDisplay.autoPanMode = .recenter
    } catch {
    self.failedToStart = true
    }
  3. Present an alert if the location display failed to start.

    ContentView.swift
    31 collapsed lines
    // Copyright 2022 Esri
    //
    // Licensed under the Apache License, Version 2.0 (the "License");
    // you may not use this file except in compliance with the License.
    // You may obtain a copy of the License at
    //
    // https://www.apache.org/licenses/LICENSE-2.0
    //
    // Unless required by applicable law or agreed to in writing, software
    // distributed under the License is distributed on an "AS IS" BASIS,
    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    // See the License for the specific language governing permissions and
    // limitations under the License.
    import SwiftUI
    import ArcGIS
    import CoreLocation
    struct ContentView: View {
    private let map = Map(basemapStyle: .arcGISTopographic)
    private let locationDisplay = LocationDisplay(dataSource: SystemLocationDataSource())
    @State private var failedToStart = false
    var body: some View {
    MapView(map: map)
    .locationDisplay(locationDisplay)
    .task {
    let locationManager = CLLocationManager()
    if locationManager.authorizationStatus == .notDetermined {
    locationManager.requestWhenInUseAuthorization()
    }
    do {
    try await locationDisplay.dataSource.start()
    locationDisplay.initialZoomScale = 40_000
    locationDisplay.autoPanMode = .recenter
    } catch {
    self.failedToStart = true
    }
    }
    .alert("Location display failed to start", isPresented: $failedToStart) {}
    }
    2 collapsed lines
    }

Run the solution

  1. Press Command + R to run the app.

  2. When the app runs, you’ll see the system prompt requesting to use the device location. Tap to either Allow once or While using the app.

  3. If the app is running on a simulator, you’ll have to provide a simulated location. Go to the Features menu of the Simulator. Under Location, choose a predefined option or enter a custom Location.

Your map should now show the device’s location, either simulated or actual.

Alternatively, you can download the tutorial solution, as follows.

Option 2: Download the solution

  1. Click the Download solution link under Solution and unzip the file to a location on your machine.

  2. Open the .xcodeproj file in Xcode.

Since the downloaded solution does not contain authentication credentials, you must first set up authentication to create credentials, and then add the developer credentials to the solution.

Set up authentication

To access the secure ArcGIS location services ArcGIS Location Services, also referred to as Location Services, are services hosted by Esri that provide geospatial functionality for developing mapping applications. They include the ArcGIS Basemap Styles service, ArcGIS Static Basemap Tiles service, ArcGIS Places service, ArcGIS Geocoding service, ArcGIS Routing service, ArcGIS GeoEnrichment service, and ArcGIS Elevation service. An ArcGIS Location Platform or ArcGIS Online account is required to use the services. Learn more used in this tutorial, you must implement API key authentication API key authentication is a type of authentication that uses an API key to authenticate requests to ArcGIS services and secure portal items. Learn more or user authentication User authentication is a type of authentication that allows users with an ArcGIS account to sign into an application and allow it to access ArcGIS content, services, and resources on their behalf. The typical authorization protocol used is OAuth2.0. Learn more using an ArcGIS Location Platform An ArcGIS Location Platform account, formerly known as an ArcGIS Developer account, is an identity associated with an ArcGIS Location Platform subscription. Learn more or an ArcGIS Online An ArcGIS Online account, also known as an ArcGIS Organization account, is an identity associated with an ArcGIS Online subscription. It can be used to access ArcGIS tools and develop applications with ArcGIS location services for an organization. Learn more account.

To complete this tutorial, click on the tab in the switcher below for your authentication type of choice, either API key authentication or User authentication.

Create a new API key access token An access token is an authorization string that provides access to secure ArcGIS content, data, and services. Its capabilities are determined by the privileges it supports. It is obtained by implementing API key authentication, User authentication, or App authentication. Learn more with privileges Privileges are a set of permissions assigned to ArcGIS accounts, developer credentials, and applications that grant access to secure resources and functionality in ArcGIS. Learn more to access the secure resources used in this tutorial.

  1. Complete the Create an API key tutorial and create an API key with the following privilege(s) Privileges are a set of permissions assigned to ArcGIS accounts, developer credentials, and applications that grant access to secure resources and functionality in ArcGIS. Learn more :

    • Privileges
      • Location services > Basemaps
  2. Copy and paste the API key access token into a safe location. It will be used in a later step.

Set developer credentials in the solution

To allow your app users to access ArcGIS location services ArcGIS Location Services, also referred to as Location Services, are services hosted by Esri that provide geospatial functionality for developing mapping applications. They include the ArcGIS Basemap Styles service, ArcGIS Static Basemap Tiles service, ArcGIS Places service, ArcGIS Geocoding service, ArcGIS Routing service, ArcGIS GeoEnrichment service, and ArcGIS Elevation service. An ArcGIS Location Platform or ArcGIS Online account is required to use the services. Learn more , use the developer credentials that you created in the Set up authentication step to authenticate requests for resources.

Pass your API Key access token to the ArcGISEnvironment.

  1. In the Project Navigator, click MainApp.swift.

  2. Set the AuthenticationMode to .apiKey.

    MainApp.swift
    // Change the `AuthenticationMode` to `.apiKey` if your application uses API key authentication.
    private var authenticationMode: AuthenticationMode { .apiKey }
  3. Set the apiKey property with your API key access token.

    MainApp.swift
    31 collapsed lines
    // Copyright 2022 Esri
    //
    // Licensed under the Apache License, Version 2.0 (the "License");
    // you may not use this file except in compliance with the License.
    // You may obtain a copy of the License at
    //
    // https://www.apache.org/licenses/LICENSE-2.0
    //
    // Unless required by applicable law or agreed to in writing, software
    // distributed under the License is distributed on an "AS IS" BASIS,
    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    // See the License for the specific language governing permissions and
    // limitations under the License.
    import SwiftUI
    import ArcGIS
    import ArcGISToolkit
    @main
    struct MainApp: App {
    // The authentication mode.
    private enum AuthenticationMode {
    case apiKey
    case user
    }
    // Change the `AuthenticationMode` to `.apiKey` if your application uses API key authentication.
    private var authenticationMode: AuthenticationMode { .apiKey }
    // Please enter an API key access token if your application uses API key authentication.
    private let apiKey = APIKey("<#YOUR-ACCESS-TOKEN#>")
    43 collapsed lines
    // Setup an `Authenticator` with OAuth configuration if your application uses OAuth credentials.
    @ObservedObject var authenticator = Authenticator(
    oAuthUserConfigurations: [
    OAuthUserConfiguration(
    // Please enter OAuth credentials for user authentication.
    portalURL: URL(string: "<#YOUR-PORTAL-URL#>")!,
    clientID: "<#YOUR-CLIENT-ID#>",
    redirectURL: URL(string: "<#YOUR-REDIRECT-URL#>")!
    )
    ]
    )
    func setAuthentication() {
    switch authenticationMode {
    case .apiKey:
    ArcGISEnvironment.apiKey = apiKey
    case .user:
    ArcGISEnvironment.authenticationManager.arcGISAuthenticationChallengeHandler = authenticator
    }
    }
    init() {
    setAuthentication()
    }
    var body: some SwiftUI.Scene {
    WindowGroup {
    ContentView()
    .authenticator(authenticator)
    .ignoresSafeArea()
    }
    }
    }

Best Practice: The access token is stored directly in the code as a convenience for this tutorial. Do not store credentials directly in source code in a production environment.

Run the solution

  1. Press Command + R to run the app.

  2. When the app runs, you’ll see the system prompt requesting to use the device location. Tap to either Allow once or While using the app.

  3. If the app is running on a simulator, you’ll have to provide a simulated location. Go to the Features menu of the Simulator. Under Location, choose a predefined option or enter a custom Location.

Your map should now show the device’s location, either simulated or actual.

What’s next?

Learn how to use additional API features, ArcGIS location services, and ArcGIS tools in these tutorials: