Namespaces

Variants
Actions

Please note that as of October 24, 2014, the Nokia Developer Wiki will no longer be accepting user contributions, including new entries, edits and comments, as we begin transitioning to our new home, in the Windows Phone Development Wiki. We plan to move over the majority of the existing entries over the next few weeks. Thanks for all your past and future contributions.

Using Location Service APIs in WP7

From Wiki
Jump to: navigation, search

This article explains how to use Location Service APIs (GeoCoordinateWatcher) in WP7.

SignpostIcon WP7 70px.png
Article Metadata
Tested with
Devices(s): WP7 Emulator
Compatibility
Platform(s):
Windows Phone 7.5
Platform Security
Capabilities: ID_CAP_LOCATION
Article
Created: vvsnaresh (10 Nov 2011)
Last edited: hamishwillee (31 Jul 2013)

Introduction

To use the WP7 Location Service APIs you need to add a reference to System.Device.dll.

The following code snippet shows how to initialize the location service, handle changes in the service’s status and obtain location data on WP7.

public partial class MainPage : PhoneApplicationPage
{
GeoCoordinateWatcher watcher;
// Click the event handler for the “Start Location” button.
private void startLocationButton_Click(object sender, RoutedEventArgs e)
{
// The watcher variable was previously declared as type GeoCoordinateWatcher.
if (watcher == null)
{
watcher = new GeoCoordinateWatcher(GeoPositionAccuracy.High); // using high accuracy
watcher.MovementThreshold = 20; // use MovementThreshold to ignore noise in the signal
watcher.StatusChanged += new EventHandler<GeoPositionStatusChangedEventArgs>(watcher_StatusChanged);
watcher.PositionChanged += new EventHandler<GeoPositionChangedEventArgs<GeoCoordinate>>(watcher_PositionChanged);
}
watcher.Start();
} // End of the Start button Click handler.
 
 
// Event handler for the GeoCoordinateWatcher.StatusChanged event.
// Implementation of the StatusChanged event handler.
// This event is raised whenever the status of the Location Service changes.
// The GeoPositionStatus enumeration that is passed in the GeoPositionStatusChangedEventArgs object,
// tells you the current status of the service.
 
void watcher_StatusChanged(object sender, GeoPositionStatusChangedEventArgs e)
{
switch (e.Status)
{
case GeoPositionStatus.Disabled:
// The Location Service is disabled or unsupported.
// Check to see whether the user has disabled the Location Service.
if (watcher.Permission == GeoPositionPermission.Denied)
{
// The user has disabled the Location Service on their device.
statusTextBlock.Text = "you have this application access to location.";
}
else
{
statusTextBlock.Text = "location is not functioning on this device";
}
break;
 
case GeoPositionStatus.Initializing:
// The Location Service is initializing.
// Disable the Start Location button.
startLocationButton.IsEnabled = false;
break;
case GeoPositionStatus.NoData:
// The Location Service is working, but it cannot get location data.
// Alert the user and enable the Stop Location button.
statusTextBlock.Text = "location data is not available.";
stopLocationButton.IsEnabled = true;
break;
 
case GeoPositionStatus.Ready:
// The Location Service is working and is receiving location data.
// Show the current position and enable the Stop Location button.
statusTextBlock.Text = "location data is available.";
stopLocationButton.IsEnabled = true;
break;
}
}
 
//When the Location Service is ready and receiving data, it will begin to raise the
// PositionChanged event and call your application’s handler if you have implemented one.
// In the event handler, access the Position member of the GeoPositionChangedEventArgs(Of T) object.
// The Position field is a GeoPosition object, which consists of a Timestamp and a GeoCoordinate
// object that contains the location information for the reading. This example accesses the latitude and longitude values.
 
void watcher_PositionChanged(object sender, GeoPositionChangedEventArgs<GeoCoordinate> e)
{
latitudeTextBlock.Text = e.Position.Location.Latitude.ToString("0.000");
longitudeTextBlock.Text = e.Position.Location.Longitude.ToString("0.000");
}
 
// Click the event handler for the “Start Location” button.
private void stopLocationButton_Click(object sender, RoutedEventArgs e)
{
watcher.Stop();
}
This page was last modified on 31 July 2013, at 23:42.
104 page views in the last 30 days.

Was this page helpful?

Your feedback about this content is important. Let us know what you think.

 

Thank you!

We appreciate your feedback.

×