后台的地理GeofenceWindows Phone 8.1(WinRT)

Question

null

null

将当前位置更改为距您先前设置的位置100m的任何位置。就会弹出通知。

    public static async Task GetLocationCapabilities()
    {
        try
        {
            var geolocator = new Geolocator();
            await geolocator.GetGeopositionAsync();
            var backgroundAccessStatus = await BackgroundExecutionManager.RequestAccessAsync();
            Debug.WriteLine("background access status" + backgroundAccessStatus);
        }
        catch (UnauthorizedAccessException e)
        {
            Debug.WriteLine(e);
        }
        catch (TaskCanceledException e)
        {
            Debug.WriteLine(e);
        }
    }

    public static void CreateGeofence(BasicGeoposition position, double radius, string id = "default")
    {
        // The Geofence is a circular area centered at (latitude, longitude) point, with the
        // radius in meter.
        var geocircle = new Geocircle(position, radius);

        // Sets the events that we want to handle: in this case, the entrace and the exit
        // from an area of intereset.
        var mask = MonitoredGeofenceStates.Entered | MonitoredGeofenceStates.Exited;

        // Specifies for how much time the user must have entered/exited the area before 
        // receiving the notification.
        var dwellTime = TimeSpan.FromSeconds(1);

        // Creates the Geofence and adds it to the GeofenceMonitor.
        var geofence = new Geofence(id, geocircle, mask, false, dwellTime);

        try
        {
            GeofenceMonitor.Current.Geofences.Add(geofence);
        }
        catch (Exception e)
        {
            Debug.WriteLine(e);
            // geofence already added to system
        }

    }

    public static async Task RegisterBackgroundTask()
    {
        try
        { 
        // Create a new background task builder
        var geofenceTaskBuilder = new BackgroundTaskBuilder()
        {
            Name = GeofenceBackgroundTaskName,
            TaskEntryPoint = "BackgroundTask.GeofenceBackgroundTask"
        };

        // Create a new location trigger
        var trigger = new LocationTrigger(LocationTriggerType.Geofence);

        // Associate the location trigger with the background task builder
        geofenceTaskBuilder.SetTrigger(trigger);

        var geofenceTask = geofenceTaskBuilder.Register();

        // Associate an event handler with the new background task
        geofenceTask.Completed += (sender, e) =>
        {
            try
            {
                e.CheckResult();
            }
            catch(Exception error)
            {
                Debug.WriteLine(error);
            }
        };
        }
        catch(Exception e)
        {
            // Background task probably exists

            Debug.WriteLine(e);
        }
    }

namespace BackgroundTask
{
    public sealed class GeofenceBackgroundTask : IBackgroundTask
    {
        public void Run(IBackgroundTaskInstance taskInstance)
        {
            var toastTemplate = ToastTemplateType.ToastText02;
            var toastXML = ToastNotificationManager.GetTemplateContent(toastTemplate);
            var textElements = toastXML.GetElementsByTagName("text");
            textElements[0].AppendChild(toastXML.CreateTextNode("You have left!"));

            var toast = new ToastNotification(toastXML);

            ToastNotificationManager.CreateToastNotifier().Show(toast);
        }
    }
}