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Get the user's location

Important

Bing Maps for Enterprise service retirement

The UWP MapControl and map services from the Windows.Services.Maps namespace rely on Bing Maps. Bing Maps for Enterprise is deprecated and will be retired, at which point the MapControl and services will no longer receive data.

For more information, see the Bing Maps Developer Center and Bing Maps documentation.

Note

MapControl and map services require a maps authentication key called a MapServiceToken. For more info about getting and setting a maps authentication key, see Request a maps authentication key.

Find the user's location and respond to changes in location. Access to the user's location is managed by privacy settings in the Windows Settings app. This topic also shows how to check if your app has permission to access the user's location.

Enable the location capability

  1. In Solution Explorer, double-click package.appxmanifest and select the Capabilities tab.
  2. In the Capabilities list, check the box for Location. This adds the location device capability to the package manifest file.
  <Capabilities>
    <!-- DeviceCapability elements must follow Capability elements (if present) -->
    <DeviceCapability Name="location"/>
  </Capabilities>

Get the current location

This section describes how to detect the user's geographic location using APIs in the Windows.Devices.Geolocation namespace.

Step 1: Request access to the user's location

Unless your app has coarse location capability (see note), you must request access to the user's location by using the RequestAccessAsync method before attempting to access the location. You must call the RequestAccessAsync method from the UI thread and your app must be in the foreground. Your app will not be able to access the user's location information until after the user grants permission to your app.*

using Windows.Devices.Geolocation;
...
var accessStatus = await Geolocator.RequestAccessAsync();

The RequestAccessAsync method prompts the user for permission to access their location. The user is only prompted once (per app). After the first time they grant or deny permission, this method no longer prompts the user for permission. To help the user change location permissions after they've been prompted, we recommend that you provide a link to the location settings as demonstrated later in this topic.

Note

The coarse location feature allows your app to obtain an intentionally obfuscated (imprecise) location without getting the user's explicit permission (the system-wide location switch must still be on, however). To learn how to utilize coarse location in your app, see the AllowFallbackToConsentlessPositions method in the Geolocator class.

Step 2: Get the user's location and register for changes in location permissions

The GetGeopositionAsync method performs a one-time reading of the current location. Here, a switch statement is used with accessStatus (from the previous example) to act only when access to the user's location is allowed. If access to the user's location is allowed, the code creates a Geolocator object, registers for changes in location permissions, and requests the user's location.

switch (accessStatus)
{
    case GeolocationAccessStatus.Allowed:
        _rootPage.NotifyUser("Waiting for update...", NotifyType.StatusMessage);

        // If DesiredAccuracy or DesiredAccuracyInMeters are not set (or value is 0), DesiredAccuracy.Default is used.
        Geolocator geolocator = new Geolocator { DesiredAccuracyInMeters = _desireAccuracyInMetersValue };

        // Subscribe to the StatusChanged event to get updates of location status changes.
        _geolocator.StatusChanged += OnStatusChanged;

        // Carry out the operation.
        Geoposition pos = await geolocator.GetGeopositionAsync();

        UpdateLocationData(pos);
        _rootPage.NotifyUser("Location updated.", NotifyType.StatusMessage);
        break;

    case GeolocationAccessStatus.Denied:
        _rootPage.NotifyUser("Access to location is denied.", NotifyType.ErrorMessage);
        LocationDisabledMessage.Visibility = Visibility.Visible;
        UpdateLocationData(null);
        break;

    case GeolocationAccessStatus.Unspecified:
        _rootPage.NotifyUser("Unspecified error.", NotifyType.ErrorMessage);
        UpdateLocationData(null);
        break;
}

Step 3: Handle changes in location permissions

The Geolocator object triggers the StatusChanged event to indicate that the user's location settings changed. That event passes the corresponding status via the argument's Status property (of type PositionStatus). Note that this method is not called from the UI thread and the Dispatcher object invokes the UI changes.

using Windows.UI.Core;
...
async private void OnStatusChanged(Geolocator sender, StatusChangedEventArgs e)
{
    await Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () =>
    {
        // Show the location setting message only if status is disabled.
        LocationDisabledMessage.Visibility = Visibility.Collapsed;

        switch (e.Status)
        {
            case PositionStatus.Ready:
                // Location platform is providing valid data.
                ScenarioOutput_Status.Text = "Ready";
                _rootPage.NotifyUser("Location platform is ready.", NotifyType.StatusMessage);
                break;

            case PositionStatus.Initializing:
                // Location platform is attempting to acquire a fix.
                ScenarioOutput_Status.Text = "Initializing";
                _rootPage.NotifyUser("Location platform is attempting to obtain a position.", NotifyType.StatusMessage);
                break;

            case PositionStatus.NoData:
                // Location platform could not obtain location data.
                ScenarioOutput_Status.Text = "No data";
                _rootPage.NotifyUser("Not able to determine the location.", NotifyType.ErrorMessage);
                break;

            case PositionStatus.Disabled:
                // The permission to access location data is denied by the user or other policies.
                ScenarioOutput_Status.Text = "Disabled";
                _rootPage.NotifyUser("Access to location is denied.", NotifyType.ErrorMessage);

                // Show message to the user to go to location settings.
                LocationDisabledMessage.Visibility = Visibility.Visible;

                // Clear any cached location data.
                UpdateLocationData(null);
                break;

            case PositionStatus.NotInitialized:
                // The location platform is not initialized. This indicates that the application
                // has not made a request for location data.
                ScenarioOutput_Status.Text = "Not initialized";
                _rootPage.NotifyUser("No request for location is made yet.", NotifyType.StatusMessage);
                break;

            case PositionStatus.NotAvailable:
                // The location platform is not available on this version of the OS.
                ScenarioOutput_Status.Text = "Not available";
                _rootPage.NotifyUser("Location is not available on this version of the OS.", NotifyType.ErrorMessage);
                break;

            default:
                ScenarioOutput_Status.Text = "Unknown";
                _rootPage.NotifyUser(string.Empty, NotifyType.StatusMessage);
                break;
        }
    });
}

Respond to location updates

This section describes how to use the PositionChanged event to receive updates of the user's location over a period of time. Because the user could revoke access to location at any time, it's important call RequestAccessAsync and use the StatusChanged event as shown in the previous section.

This section assumes that you've already enabled the location capability and called RequestAccessAsync from the UI thread of your foreground app.

Step 1: Define the report interval and register for location updates

In this example, a switch statement is used with accessStatus (from the previous example) to act only when access to the user's location is allowed. If access to the user's location is allowed, the code creates a Geolocator object, specifies the tracking type, and registers for location updates.

The Geolocator object can trigger the PositionChanged event based on a change in position (distance-based tracking) or a change in time (periodic-based tracking).

If neither property is set, a position is returned every 1 second (equivalent to ReportInterval = 1000). Here, a 2 second (ReportInterval = 2000) report interval is used.

using Windows.Devices.Geolocation;
...
var accessStatus = await Geolocator.RequestAccessAsync();

switch (accessStatus)
{
    case GeolocationAccessStatus.Allowed:
        // Create Geolocator and define periodic-based tracking (2 second interval).
        _geolocator = new Geolocator { ReportInterval = 2000 };

        // Subscribe to the PositionChanged event to get location updates.
        _geolocator.PositionChanged += OnPositionChanged;

        // Subscribe to StatusChanged event to get updates of location status changes.
        _geolocator.StatusChanged += OnStatusChanged;

        _rootPage.NotifyUser("Waiting for update...", NotifyType.StatusMessage);
        LocationDisabledMessage.Visibility = Visibility.Collapsed;
        StartTrackingButton.IsEnabled = false;
        StopTrackingButton.IsEnabled = true;
        break;

    case GeolocationAccessStatus.Denied:
        _rootPage.NotifyUser("Access to location is denied.", NotifyType.ErrorMessage);
        LocationDisabledMessage.Visibility = Visibility.Visible;
        break;

    case GeolocationAccessStatus.Unspecified:
        _rootPage.NotifyUser("Unspecified error!", NotifyType.ErrorMessage);
        LocationDisabledMessage.Visibility = Visibility.Collapsed;
        break;
}

Step 2: Handle location updates

The Geolocator object triggers the PositionChanged event to indicate that the user's location changed or time has passed, depending on how you've configured it. That event passes the corresponding location via the argument's Position property (of type Geoposition). In this example, the method is not called from the UI thread and the Dispatcher object invokes the UI changes.

using Windows.UI.Core;
...
async private void OnPositionChanged(Geolocator sender, PositionChangedEventArgs e)
{
    await Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () =>
    {
        _rootPage.NotifyUser("Location updated.", NotifyType.StatusMessage);
        UpdateLocationData(e.Position);
    });
}

Change the location privacy settings

If the location privacy settings don't allow your app to access the user's location, we recommend that you provide a convenient link to the location privacy settings in the Settings app. In this example, a Hyperlink control is used navigate to the ms-settings:privacy-location URI.

<!--Set Visibility to Visible when access to location is denied -->  
<TextBlock x:Name="LocationDisabledMessage" FontStyle="Italic"
           Visibility="Collapsed" Margin="0,15,0,0" TextWrapping="Wrap">
    <Run Text="This app is not able to access Location. Go to "/>
        <Hyperlink NavigateUri="ms-settings:privacy-location">
            <Run Text="Settings"/>
        </Hyperlink>
    <Run Text=" to check the location privacy settings."/>
</TextBlock>

Alternatively, your app can call the LaunchUriAsync method to launch the Settings app from code. For more info, see Launch the Windows Settings app.

using Windows.System;
...
bool result = await Launcher.LaunchUriAsync(new Uri("ms-settings:privacy-location"));

Troubleshoot your app

Before your app can access the user's location, Location must be enabled on the device. In the Settings app, check that the following location privacy settings are turned on:

  • Location for this device... is turned on (not applicable in Windows 10 Mobile)
  • The location services setting, Location, is turned on
  • Under Choose apps that can use your location, your app is set to on