/// ------------------------------------------------------------------------------------------------
/// ------------------------------------------------------------------------------------------------
#region Private Functions
#region Get Current Location
public async Task <Plugin.Geolocator.Abstractions.Position> GetCurrentLocation()
{
try
{
var locator = CrossGeolocator.Current;
//locator.AllowsBackgroundUpdates = true;
//locator.DesiredAccuracy = 50;
_posistion = await locator.GetPositionAsync(1000);
}
catch (Plugin.Geolocator.Abstractions.GeolocationException geoException)
{
AppContext.AppContext.CurrentLocation = null;
if (geoException.Message.Contains("Unavailable"))
{
await SplitView.DisplayAlert(" GPS Disabled ", " Please enable the GPS to access your current location ", "OK", null);
}
if (geoException.Message.Contains("Unauthorized"))
{
await SplitView.DisplayAlert("Get Device Location", " Please grant permission for this application to access your current location ", "OK", null);
}
_posistion = null;
}
catch (Exception ex)
{
LogTracking.LogTrace(ex.ToString());
AppContext.AppContext.CurrentLocation = null;
}
return(_posistion);
}
public async Task UpdateLocationAsync(Plugin.Geolocator.Abstractions.Position position, Address address, string accessToken)
{
try
{
var client = new System.Net.Http.HttpClient();
client.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", accessToken);
var location = new GeoContacts.SharedModels.LocationUpdate
{
Country = address.CountryCode,
Position = new Microsoft.Azure.Documents.Spatial.Point(position.Longitude, position.Latitude),
State = address.AdminArea,
Town = address.Locality
};
var json = Newtonsoft.Json.JsonConvert.SerializeObject(location);
var content = new System.Net.Http.StringContent(json);
var resp = await client.PostAsync(CommonConstants.FunctionUrl, content);
var respBody = await resp.Content.ReadAsStringAsync();
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine($"ERROR: {ex.Message}");
}
}
public PointOfInterest(string name, string type, Position position)
: this()
{
_name = name ?? "";
_type = type ?? "";
_position = position;
}
/*---------------------------------*/
/*Map functions and event handeling*/
public async void InitMapAndTracking()
{
//Get the current user location
DBPosition = LastPosition = await GetUserStartLocation();
//Get the style of the selected map
var styleFile = await ChangeMapStyle();
await Task.Run(() =>
{
Device.BeginInvokeOnMainThread(() =>
{
//Changing the style of the map
CustomMap.MapStyle = GoogleMaps.MapStyle.FromJson(styleFile);
//Standard Map settings
CustomMap.UiSettings.ZoomControlsEnabled = false;
CustomMap.UiSettings.MyLocationButtonEnabled = true;
//move the users position on the map
CustomMap.InitialCameraUpdate = GoogleMaps.CameraUpdateFactory.NewPositionZoom(new GoogleMaps.Position(DBPosition.Latitude, DBPosition.Longitude), 17.5);
});
});
Current.CustomMap = CustomMap;
//Store the long and lat data in the CU variable
Current.CU.Latitude = DBPosition.Latitude;
Current.CU.Longitude = DBPosition.Longitude;
await GetPlaces(); //Calls the function to get all the places nearby
await StartListening(); //Calls the function that will listen for location changes (every second)
}
protected override void OnAppearing()
{
Device.BeginInvokeOnMainThread(async() =>
{
if (_geolocator.IsGeolocationEnabled)
{
_position = await _geolocator.GetLastKnownLocationAsync();
if (_position == null)
{
_position = await _geolocator.GetPositionAsync();
}
var formsMapPosition = new Xamarin.Forms.Maps.Position(_position.Latitude, _position.Longitude);
var mapSpan = MapSpan.FromCenterAndRadius(formsMapPosition, Distance.FromKilometers(1.5));
_map.MoveToRegion(mapSpan);
Incidents = await AdaptatonEndpoint.Instance.GetIncidents();
foreach (var incident in Incidents)
{
_map.Pins.Add(new Pin
{
Position = new Xamarin.Forms.Maps.Position((double)incident.Latitude,
(double)incident.Longitude),
Label = incident.Id
});
}
}
else
{
await DisplayAlert("Un momento", "Debes activar tu GPS para usar la aplicaciĆ³n.", "OK");
}
});
}
private async void buttonClicked(object sender, EventArgs e)
{
IGeolocator locator = CrossGeolocator.Current;
locator.DesiredAccuracy = 50;
if (locator.IsGeolocationAvailable)
{
if (locator.IsGeolocationEnabled)
{
try
{
position = await locator.GetPositionAsync(timeoutMilliseconds: 10000);
latLabel.Text = "Latitude: " + position.Latitude;
lonLabel.Text = "Longitude: " + position.Longitude;
System.Diagnostics.Debug.WriteLine("TimeStamp: " + position.Timestamp);
}
catch (GeolocationException ex)
{
System.Diagnostics.Debug.WriteLine(ex.InnerException);
await DisplayAlert("Error", "Unauthorized", "OK");
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine(ex.InnerException);
}
}
else
await DisplayAlert("Error", "Geo sensors is not turned on.\nPlease turn on it.", "OK");
}
else
await DisplayAlert("Error", "This device does not have any geo sensors or enough permission to use it.", "OK");
}
protected async override void OnElementChanged(ElementChangedEventArgs <Map> e)
{
if (_map != null)
{
_map.MapClick -= googleMap_MapClick;
}
base.OnElementChanged(e);
if (Control != null)
{
((MapView)Control).GetMapAsync(this);
}
location = CrossGeolocator.Current;
location.DesiredAccuracy = 100;
try
{
position = await location.GetPositionAsync(TimeSpan.FromSeconds(10));
await((MapTapRenderer)Element).ChangePosition(new Xamarin.Forms.Maps.Position(position.Latitude, position.Longitude));
Console.WriteLine("pos android" + position.Latitude.ToString() + " , " + position.Longitude.ToString());
SetMarker(position.Latitude, position.Longitude);
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
}
private void MoveMap(Plugin.Geolocator.Abstractions.Position position)
{
var span = (MapSpan.FromCenterAndRadius(new Xamarin.Forms.Maps.Position(position.Latitude, position.Longitude),
Distance.FromMiles(1)));
locationsMap.MoveToRegion(span);
}
public AddNewCasePointOnMapView(IMapView mapview, GeoLocation.Position casePosition)
{
try
{
_mapview = mapview;
_casePosition = casePosition;
InitializeComponent();
AppContext.AppContext.NewRecordInProgress = true;
Tapgestures();
if (Device.OS == TargetPlatform.Android)
{
SplitView.MapView?.ClearPin();
MoveMapPosition();
AndroidMapView.HideLocator();
var googleMap = (AndroidMapView)SplitView.MapView;
GlMapView.Children.Clear();
GlMapView.Children.Add(googleMap, 0, 0);
}
else
{
var formsMap = (WindowsMapView)mapview;
GlMapView.Children.Add(formsMap, 0, 0);
}
MoveToPosition += MoveMapPosition;
_slowmethod = SlowConnectionAlert;
_token = CancellationToken.None;
SlowConnection();
}
catch (Exception ex)
{
LogTracking.LogTrace(ex.ToString());
}
}
private void MoveMap(Plugin.Geolocator.Abstractions.Position position)
{
var center = new Xamarin.Forms.Maps.Position(position.Latitude, position.Longitude); //koordinatlari aliyoruz.ekranin merkezinde olacak.
var span = new MapSpan(center, 0.1, 0.1); //sayisal degerler haritanin ne kadar uzaktan acilmasi gerektigini belirtir.
locationsMap.MoveToRegion(span); //istenilen bolgeye haritanin gitmesini sagliyoruz.
}
public static async Task <bool> getCurrentDeviceLatitudeLongitude()
{
int gotLocation = 0;
try
{
var locator = CrossGeolocator.Current;
locator.DesiredAccuracy = 100;
if (locator.IsGeolocationAvailable && locator.IsGeolocationEnabled)
{
var position = await locator.GetPositionAsync(TimeSpan.FromMilliseconds(1500));
currentDeviceLatitude = position.Latitude;
currentDeviceLongitude = position.Longitude;
// App.UserPreferences.SetString("LastKnownLongitude", currentDeviceLongitude.ToString());
// App.UserPreferences.SetString("LastKnownLatitude", currentDeviceLatitude.ToString());
if (currentDeviceLatitude != 0 && currentDeviceLongitude != 0)
{
gotLocation = 1;
}
}
else if (locator.IsGeolocationEnabled)
{
Plugin.Geolocator.Abstractions.Position Lastknownpositions = await locator.GetLastKnownLocationAsync();
if (Lastknownpositions != null)
{
currentDeviceLatitude = Lastknownpositions.Latitude;
currentDeviceLongitude = Lastknownpositions.Longitude;
}
gotLocation = 1;
}
if (LocationService.currentDeviceLatitude == 0 && LocationService.currentDeviceLongitude == 0)
{
gotLocation = 0;
}
if (gotLocation == 1)
{
return(true);
}
else
{
return(false);
}
}
catch (Exception exNew)
{
Debug.Write(exNew);
return(false);
}
}
private void CrossGeolocator_Current_PositionChanged(object sender, PositionEventArgs e)
{
Device.BeginInvokeOnMainThread(async() =>
{
Models.Location local = new Models.Location();
Plugin.Geolocator.Abstractions.Position position = e.Position;
if (Cposition != e.Position)
{
Cposition = e.Position;
mainmap.MoveToRegion(MapSpan.FromCenterAndRadius(new Xamarin.Forms.Maps.Position(position.Latitude, position.Longitude), Distance.FromMiles(1)).WithZoom(2));
loader.IsVisible = false;
mainmap.IsVisible = true;
local.Lat = position.Latitude;
local.Lng = position.Longitude;
if (Trip.Key != null)
{
_firebaseDatabase.UpdateTripDriverLocation(Trip.Key, local);
if (Trip.Status == "Started")
{
_firebaseDatabase.UpdateTripLocation(Trip.Key, local);
}
}
}
});
}
protected override void OnAppearing()
{
Device.BeginInvokeOnMainThread(async() =>
{
if (_geolocator.IsGeolocationEnabled)
{
_position = await _geolocator.GetLastKnownLocationAsync();
if (_position == null)
{
_position = await _geolocator.GetPositionAsync();
}
var formsMapPosition = new Xamarin.Forms.Maps.Position(_position.Latitude, _position.Longitude);
var mapSpan = MapSpan.FromCenterAndRadius(formsMapPosition, Distance.FromKilometers(1));
_map.MoveToRegion(mapSpan);
MyPositionPin = new Pin
{
Address = "Mi ubicaciĆ³n",
Position = formsMapPosition,
Type = PinType.Generic,
Label = "Mi ubicaciĆ³n"
};
_map.Pins.Add(MyPositionPin);
}
else
{
await DisplayAlert("Un momento", "Debes activar tu GPS para usar la aplicaciĆ³n.", "OK");
}
});
}
private void moveMapToPosition(Plugin.Geolocator.Abstractions.Position position)
{
mapView.MoveToRegion(
MapSpan.FromCenterAndRadius(
new Xamarin.Forms.GoogleMaps.Position(position.Latitude, position.Longitude), Distance.FromMiles(1)));
System.Diagnostics.Debug.WriteLine("Map Moved");
}
private void MoveMap(Plugin.Geolocator.Abstractions.Position position)
{
var center = new Xamarin.Forms.Maps.Position(position.Latitude, position.Longitude);
var span = new Xamarin.Forms.Maps.MapSpan(center, 1, 1);
locationsMap.MoveToRegion(span);
}
async void SetLocationOnMap()
{
var status = await CrossPermissions.Current.CheckPermissionStatusAsync(Permission.Location);
if (status != PermissionStatus.Granted)
{
await DependencyService.Get <IPermissionServices>().GetPermission(this);
}
var locator = CrossGeolocator.Current;
TimeSpan ts = TimeSpan.FromTicks(1000000);
Plugin.Geolocator.Abstractions.Position position = await locator.GetPositionAsync(ts);
IEnumerable <Address> addresses = await locator.GetAddressesForPositionAsync(position, "AIzaSyDminfXt_CoSb9UTXpPFZwQIG2lDduDMjs");
Address address = addresses.FirstOrDefault();
//Address address = (addresses.ToArray())[0];
entryHelperRegSearch3.Placeholder = address.FeatureName + "," + address.SubLocality + "," + address.Locality;
var pin = new Pin()
{
Type = PinType.Place,
Position = new Xamarin.Forms.Maps.Position(position.Latitude, position.Longitude),
Label = address.FeatureName,
Address = address.FeatureName + "," + address.SubLocality + "," + address.Locality,
Id = "1"
};
mapHelperRegister.Pins.Add(pin);
//Pin pin = mapRegister.Pins.FirstOrDefault();
mapHelperRegister.MoveToRegion(MapSpan.FromCenterAndRadius(new Xamarin.Forms.Maps.Position(position.Latitude, position.Longitude), Distance.FromMiles(0.2)));
mapHelperRegister.IsShowingUser = true;
}
async Task <Plugin.Geolocator.Abstractions.Position> GetCurrentLocation()
{
Plugin.Geolocator.Abstractions.Position position = null;
try
{
var locator = CrossGeolocator.Current;
locator.DesiredAccuracy = 100;
if (locator.IsGeolocationAvailable && locator.IsGeolocationEnabled)
{
position = await locator.GetLastKnownLocationAsync();
if (position == null)
{
position = await locator.GetPositionAsync(TimeSpan.FromSeconds(20), null, true);
}
if (position != null)
{
var output = string.Format("Time: {0} \nLat: {1} \nLong: {2} \nAltitude: {3} \nAltitude Accuracy: {4} \nAccuracy: {5} \nHeading: {6} \nSpeed: {7}",
position.Timestamp, position.Latitude, position.Longitude,
position.Altitude, position.AltitudeAccuracy, position.Accuracy, position.Heading, position.Speed);
Debug.WriteLine(output);
}
}
}
catch (Exception ex)
{
//Display error as we have timed out or can't get location.
}
return(position);
}
// Update GPS location displays and database
private async void updateGPSDataList(Plugin.Geolocator.Abstractions.Position position)
{
Debug.WriteLine("Position changed: " + position.Latitude);
Debug.WriteLine("Position changed: " + position.Longitude);
StaticDataModel.Lattitude = position.Latitude;
StaticDataModel.Longitude = position.Longitude;
}
public override void Stop()
{
lock (_locker)
{
base.Stop();
_previousPosition = null; // reset previous location so it doesn't get used when this probe is restarted.
}
}
public static CurrentLocationPost GeolocatorToDataContract(this Geo.Position position)
{
return(new CurrentLocationPost()
{
Latitude = position.Latitude,
Longitude = position.Longitude
});
}
public async override void OnNavigatingTo(NavigationParameters parameters)
{
if (CrossConnectivity.Current.IsConnected)
{
LocationFinder finder = new LocationFinder();
_position = await finder.GetCurrentLocation();
}
}
/// <summary>
/// update map region for display
/// </summary>
public void UpdateMapRegion(Plugin.Geolocator.Abstractions.Position position)
{
CurrentPosition = new Xamarin.Forms.Maps.Position(position.Latitude, position.Longitude);
MapCenter = CurrentPosition;
Distance distance = MapRegion != null ? MapRegion.Radius : Distance.FromKilometers(30);
MapRegion = MapSpan.FromCenterAndRadius(CurrentPosition, distance);
}
// bespoke method for moving map (refactored here) 7-63
private void MoveMap(Plugin.Geolocator.Abstractions.Position position)
{
var centre = new Xamarin.Forms.Maps.Position(position.Latitude, position.Longitude);
var span = new Xamarin.Forms.Maps.MapSpan(centre, 1, 1); // 1 degree of lat & lng is the region to span around the centre
locationsMap.MoveToRegion(span);
// For region, supply region centre, and degrees of lat & lng to show as a region around/spanning centre
}
void UpdateWorkFieldAndObj(Plugin.Geolocator.Abstractions.Position oldValue, Plugin.Geolocator.Abstractions.Position newValue)
{
var conventer = new WorkoutConventer();
var surveyTime = (DateTime.Now.Ticks - startWorkout.Ticks + lastInterval.Ticks) / 10000000;//measurement approximate accuracy//seconds
WorkoutData = conventer.ValueObject(new MapPreparedData(WorkoutData), oldValue, newValue, NumberOfPoint, surveyTime);
NewWorkoutPoint = newValue;
RefreshWorkFieldAndObj(newValue);
}
/*
* async void SetLocationOnMap()
* {
* var locator = CrossGeolocator.Current;
* TimeSpan ts = TimeSpan.FromTicks(1000000);
* Plugin.Geolocator.Abstractions.Position position = await locator.GetPositionAsync(ts);
* IEnumerable<Address> addresses = await locator.GetAddressesForPositionAsync(position, "AIzaSyDminfXt_CoSb9UTXpPFZwQIG2lDduDMjs");
* Address address = addresses.FirstOrDefault();
* //Address address = (addresses.ToArray())[0];
* entryRegSearch3.Placeholder = address.FeatureName + "," + address.SubLocality + "," + address.Locality;
* var pin = new Pin()
* {
* Type = PinType.Place,
* Position = new Xamarin.Forms.Maps.Position(position.Latitude, position.Longitude),
* Label = address.FeatureName,
* Address = address.FeatureName + "," + address.SubLocality + "," + address.Locality,
* Id = "1"
* };
* // mapRegister.Pins.Add(pin);
* //Pin pin = mapRegister.Pins.FirstOrDefault();
*
* // mapRegister.MoveToRegion(MapSpan.FromCenterAndRadius(new Xamarin.Forms.Maps.Position(position.Latitude, position.Longitude), Distance.FromMiles(0.2)));
* // mapRegister.IsShowingUser = true;
* }
*/
async void SetLocationOnMap()
{
try
{
var status = await CrossPermissions.Current.CheckPermissionStatusAsync(Permission.LocationAlways);
if (status != PermissionStatus.Granted)
{
if (await CrossPermissions.Current.ShouldShowRequestPermissionRationaleAsync(Permission.Location))
{
//await DisplayAlert("Need location", "Helpa need that location", "OK");
}
var results = await CrossPermissions.Current.RequestPermissionsAsync(Permission.Location);
if (results.ContainsKey(Permission.Location))
{
status = results[Permission.Location];
}
}
if (status == PermissionStatus.Granted)
{
await DependencyService.Get <IPermissionServices>().CheckAndTurnOnGPS(this);
Plugin.Geolocator.Abstractions.Position position = await CrossGeolocator.Current.GetPositionAsync();
var addr = await CrossGeolocator.Current.GetAddressesForPositionAsync(new Plugin.Geolocator.Abstractions.Position(position.Latitude, position.Longitude), "AIzaSyDminfXt_CoSb9UTXpPFZwQIG2lDduDMjs");
var a = addr.FirstOrDefault();
var loc = a.FeatureName + "," + a.SubLocality + "," + a.Locality + "," + a.CountryName + "," + a.PostalCode;
mapRegister.Pins.Clear();
mapRegister.Pins.Add(new Pin()
{
Type = PinType.Place,
Position = new Xamarin.Forms.Maps.Position(position.Latitude, position.Longitude),
Label = a.FeatureName,
Address = a.FeatureName + "," + a.SubLocality + "," + a.Locality,
Id = "1"
});
mapRegister.MoveToRegion(MapSpan.FromCenterAndRadius(new Xamarin.Forms.Maps.Position(position.Latitude, position.Longitude), Distance.FromMiles(0.2)));
mapRegister.IsShowingUser = true;
//MessagingCenter.Send<Register2, string>(this, "Current Address", loc);
}
else if (status != PermissionStatus.Unknown)
{
//await DisplayAlert("Location Denied", "Please allow location permission to get your location for Helpa app in Device setting", "OK");
}
}
catch (Exception ex)
{
//await DisplayAlert("Error", ex.Message, "OK");
}
}
private void MoveMap(Plugin.Geolocator.Abstractions.Position position)
{
//get the center in lat, long
var center = new Xamarin.Forms.Maps.Position(position.Latitude, position.Longitude);
//get the span of the map with the center
var mapspan = new Xamarin.Forms.Maps.MapSpan(center, 0.0015d, 0.0015d);
//now move to the region
customMap.MoveToRegion(mapspan);
}
/*Used to calculate the distance between the users current position and the place*/
public async Task CalculateDistance(Geolocator.Position CurrentPosition)
{
await Task.Run(() =>
{
//Used to re-calculate the distance for each place in the list
foreach (Place place in Current.Places)
{
place.Distance = 6371 * Math.Acos(Math.Cos(ConvertToRadians(CurrentPosition.Latitude)) * Math.Cos(ConvertToRadians(place.Latitude)) * Math.Cos(ConvertToRadians(place.Longitude) - ConvertToRadians(CurrentPosition.Longitude)) + Math.Sin(ConvertToRadians(CurrentPosition.Latitude)) * Math.Sin(ConvertToRadians(place.Latitude)));
}
});
}
public void CheckLocation()
{
position = new Plugin.Geolocator.Abstractions.Position();
var locator = CrossGeolocator.Current;
locator.DesiredAccuracy = 50;
Task.Run(async() => {
position = await locator.GetPositionAsync(TimeSpan.FromMilliseconds(1000));
Debug.WriteLine(position.Latitude);
});
}
private async void GetLocation()
{
if (hasLocationPermission)
{
var locator = CrossGeolocator.Current;
var position = await locator.GetPositionAsync();
mainPosition = position;
MoveMap(position);
}
}
private async Task<Position> FetchLocation()
{
try
{
_lastPosition = await _geolocator.GetPositionAsync(timeoutMilliseconds: 10000);
}
catch (Exception e)
{
}
return _lastPosition;
}
private async void SetLocationAsync()
{
if (IsLocationAvailable() && hasLocationPermission)
{
var geolocator = CrossGeolocator.Current;
Position position = await geolocator.GetPositionAsync();
MoveMap(position);
SetVenuesPinsAsync(position);
}
}
public static double GetDistance(Plugin.Geolocator.Abstractions.Position pos1, Plugin.Geolocator.Abstractions.Position pos2, Xamarin.Forms.GoogleMaps.DistanceType type)
{
double R = (type == Xamarin.Forms.GoogleMaps.DistanceType.Miles) ? 3960 : 6371;
double dLat = ToRadian(pos2.Latitude - pos1.Latitude);
double dLon = ToRadian(pos2.Longitude - pos1.Longitude);
double a = Math.Sin(dLat / 2) * Math.Sin(dLat / 2) +
Math.Cos(ToRadian(pos1.Latitude)) * Math.Cos(ToRadian(pos2.Latitude)) *
Math.Sin(dLon / 2) * Math.Sin(dLon / 2);
double c = 2 * Math.Asin(Math.Min(1, Math.Sqrt(a)));
double d = R * c;
return(d);
}
public MapView(Plugin.Geolocator.Abstractions.Position _position)
{
InitializeComponent();
this.Title = "Location";
position = _position;
location = LoginPage.Location;
openingLocation = LoginPage.locationLabel;
mapView.HeightRequest = App.ScreenHeight;
mapView.WidthRequest = App.ScreenWidth;
}
public async Task <Plugin.Geolocator.Abstractions.Position> getDetailPlace(string id)
{
var detail = await _service.getDetailPlaceInfo(id).ConfigureAwait(false);
var location = detail["result"]["geometry"]["location"];
var latitude = double.Parse(location["lat"].ToString());
var longitude = double.Parse(location["lng"].ToString());
var position = new Plugin.Geolocator.Abstractions.Position();
position.Latitude = latitude;
position.Longitude = longitude;
return(position);
}
public SpeedDatum(DateTimeOffset timestamp, Position previousPosition, Position currentPosition)
: base(timestamp, 0)
{
double distanceKM;
double timeHours;
_kph = SpeedDatum.CalculateSpeedKPH(previousPosition, currentPosition, out distanceKM, out timeHours);
if (previousPosition.Accuracy >= 0 && currentPosition.Accuracy >= 0)
{
double maximumDistanceKM = distanceKM + previousPosition.Accuracy / 1000f + currentPosition.Accuracy / 1000f;
double maximumSpeedKPH = maximumDistanceKM / timeHours;
Accuracy = (float)(maximumSpeedKPH - _kph);
}
}
public Position(Position position)
{
if (position == null)
throw new ArgumentNullException("position");
Timestamp = position.Timestamp;
Latitude = position.Latitude;
Longitude = position.Longitude;
Altitude = position.Altitude;
AltitudeAccuracy = position.AltitudeAccuracy;
Accuracy = position.Accuracy;
Heading = position.Heading;
Speed = position.Speed;
}
private GpsReceiver()
{
_readingIsComing = false;
_readingWait = new ManualResetEvent(false);
_reading = null;
_readingTimeoutMS = 120000;
_locator = CrossGeolocator.Current;
_listenerHeadings = new List<Tuple<EventHandler<PositionEventArgs>, bool>>();
_locator.PositionChanged += (o, e) =>
{
SensusServiceHelper.Get().Logger.Log("GPS position has changed.", LoggingLevel.Verbose, GetType());
if (PositionChanged != null)
PositionChanged(o, e);
};
}
public void OnLocationChanged(Location location)
{
if (location.Provider != this.activeProvider)
{
if (this.activeProvider != null && this.manager.IsProviderEnabled(this.activeProvider))
{
LocationProvider pr = this.manager.GetProvider(location.Provider);
TimeSpan lapsed = GetTimeSpan(location.Time) - GetTimeSpan(this.lastLocation.Time);
if (pr.Accuracy > this.manager.GetProvider(this.activeProvider).Accuracy
&& lapsed < timePeriod.Add(timePeriod))
{
location.Dispose();
return;
}
}
this.activeProvider = location.Provider;
}
var previous = Interlocked.Exchange(ref this.lastLocation, location);
if (previous != null)
previous.Dispose();
var p = new Position();
if (location.HasAccuracy)
p.Accuracy = location.Accuracy;
if (location.HasAltitude)
p.Altitude = location.Altitude;
if (location.HasBearing)
p.Heading = location.Bearing;
if (location.HasSpeed)
p.Speed = location.Speed;
p.Longitude = location.Longitude;
p.Latitude = location.Latitude;
p.Timestamp = GeolocatorImplementation.GetTimestamp(location);
var changed = PositionChanged;
if (changed != null)
changed(this, new PositionEventArgs(p));
}
public ListeningSpeedProbe()
{
_positionChangedHandler = (o, e) =>
{
if (e.Position == null)
return;
lock (_locker)
{
SensusServiceHelper.Get().Logger.Log("Received position change notification.", LoggingLevel.Verbose, GetType());
if (_previousPosition == null)
_previousPosition = e.Position;
else if (e.Position.Timestamp > _previousPosition.Timestamp) // it has happened (rarely) that positions come in out of order...drop any such positions.
{
StoreDatum(new SpeedDatum(e.Position.Timestamp, _previousPosition, e.Position));
_previousPosition = e.Position;
}
}
};
}
private GpsReceiver()
{
_readingIsComing = false;
_readingWait = new ManualResetEvent(false);
_reading = null;
_readingTimeoutMS = 120000;
_minimumTimeHintMS = 5000;
_locator = CrossGeolocator.Current;
_locator.AllowsBackgroundUpdates = true;
_locator.PausesLocationUpdatesAutomatically = false;
_locator.DesiredAccuracy = 50; // setting this too low appears to result in very delayed GPS fixes.
_listenerHeadings = new List<Tuple<EventHandler<PositionEventArgs>, bool>>();
_locator.PositionChanged += (o, e) =>
{
SensusServiceHelper.Get().Logger.Log("GPS position has changed.", LoggingLevel.Verbose, GetType());
if (PositionChanged != null)
PositionChanged(o, e);
};
}
protected override sealed void StopListening()
{
GpsReceiver.Get().RemoveListener(_positionChangedHandler);
_previousPosition = null;
}
protected override sealed void StartListening()
{
_previousPosition = null;
GpsReceiver.Get().AddListener(_positionChangedHandler, false);
}
/// <summary>
/// Calculates distance (KM) given two lat-lon positions (http://www.movable-type.co.uk/scripts/latlong.html)
/// </summary>
/// <returns>Distance in KM.</returns>
/// <param name="previousPosition">Previous position.</param>
/// <param name="currentPosition">Current position.</param>
public static double CalculateDistanceKM(Position previousPosition, Position currentPosition)
{
double Ļ1 = DegreesToRadians(previousPosition.Latitude);
double Ļ2 = DegreesToRadians(currentPosition.Latitude);
double ĪĻ = DegreesToRadians(currentPosition.Latitude - previousPosition.Latitude);
double ĪĪ» = DegreesToRadians(currentPosition.Longitude - previousPosition.Longitude);
double a = Math.Pow(Math.Sin(ĪĻ / 2), 2) +
Math.Cos(Ļ1) *
Math.Cos(Ļ2) *
Math.Pow(Math.Sin(ĪĪ» / 2), 2);
double c = 2 * Math.Atan2(Math.Sqrt(a), Math.Sqrt(1 - a));
return 6371 * c;
}
protected override void InternalStart()
{
lock (_locker)
{
_previousPosition = null; // do this before starting the base-class poller so it doesn't race to grab a stale previous location.
base.InternalStart();
}
}
/// <summary>
/// Gets a GPS reading, reusing an old one if it isn't too old. Will block the current thread while waiting for a GPS reading. Should not
/// be called from the main / UI thread, since GPS runs on main thread (will deadlock).
/// </summary>
/// <returns>The reading.</returns>
/// <param name="maxReadingAgeForReuseMS">Maximum age of old reading to reuse (milliseconds).</param>
/// <param name="cancellationToken">Cancellation token.</param>
public Position GetReading(int maxReadingAgeForReuseMS, CancellationToken cancellationToken)
{
lock (_locker)
{
try
{
SensusServiceHelper.Get().AssertNotOnMainThread(GetType() + " GetReading");
}
catch (Exception)
{
return null;
}
if (SensusServiceHelper.Get().ObtainPermission(Permission.Location) != PermissionStatus.Granted)
return null;
// reuse existing reading if it isn't too old
if (_reading != null && maxReadingAgeForReuseMS > 0)
{
double readingAgeMS = (DateTimeOffset.UtcNow - _reading.Timestamp).TotalMilliseconds;
if (readingAgeMS <= maxReadingAgeForReuseMS)
{
SensusServiceHelper.Get().Logger.Log("Reusing previous GPS reading, which is " + readingAgeMS + "ms old (maximum = " + maxReadingAgeForReuseMS + "ms).", LoggingLevel.Verbose, GetType());
return _reading;
}
}
if (_readingIsComing)
SensusServiceHelper.Get().Logger.Log("A GPS reading is coming. Will wait for it.", LoggingLevel.Debug, GetType());
else
{
_readingIsComing = true; // tell any subsequent, concurrent callers that we're taking a reading
_readingWait.Reset(); // make them wait
new Thread(async () =>
{
try
{
SensusServiceHelper.Get().Logger.Log("Taking GPS reading.", LoggingLevel.Debug, GetType());
DateTimeOffset readingStart = DateTimeOffset.UtcNow;
_locator.DesiredAccuracy = SensusServiceHelper.Get().GpsDesiredAccuracyMeters;
Position newReading = await _locator.GetPositionAsync(timeoutMilliseconds: _readingTimeoutMS, token: cancellationToken);
DateTimeOffset readingEnd = DateTimeOffset.UtcNow;
if (newReading != null)
{
// create copy of new position to keep return references separate, since the same Position object is returned multiple times when a change listener is attached.
_reading = new Position(newReading);
SensusServiceHelper.Get().Logger.Log("GPS reading obtained in " + (readingEnd - readingStart).TotalSeconds + " seconds.", LoggingLevel.Verbose, GetType());
}
}
catch (Exception ex)
{
SensusServiceHelper.Get().Logger.Log("GPS reading failed: " + ex.Message, LoggingLevel.Normal, GetType());
_reading = null;
}
_readingWait.Set(); // tell anyone waiting on the shared reading that it is ready
_readingIsComing = false; // direct any future calls to this method to get their own reading
}).Start();
}
}
_readingWait.WaitOne(_readingTimeoutMS);
if (_reading == null)
SensusServiceHelper.Get().Logger.Log("GPS reading is null.", LoggingLevel.Normal, GetType());
return _reading;
}
internal static Position GetPosition(GeoPosition<GeoCoordinate> position)
{
if (position.Location.IsUnknown)
return null;
var p = new Position();
p.Accuracy = position.Location.HorizontalAccuracy;
p.Longitude = position.Location.Longitude;
p.Latitude = position.Location.Latitude;
if (!Double.IsNaN(position.Location.VerticalAccuracy) && !Double.IsNaN(position.Location.Altitude))
{
p.AltitudeAccuracy = position.Location.VerticalAccuracy;
p.Altitude = position.Location.Altitude;
}
if (!Double.IsNaN(position.Location.Course))
p.Heading = position.Location.Course;
if (!Double.IsNaN(position.Location.Speed))
p.Speed = position.Location.Speed;
p.Timestamp = position.Timestamp.ToUniversalTime();
return p;
}
public double KmDistanceTo(Position position)
{
return SpeedDatum.CalculateDistanceKM(_position, position);
}
private void UpdatePosition (CLLocation location)
{
Position p = (this.position == null) ? new Position () : new Position (this.position);
if (location.HorizontalAccuracy > -1)
{
p.Accuracy = location.HorizontalAccuracy;
p.Latitude = location.Coordinate.Latitude;
p.Longitude = location.Coordinate.Longitude;
}
if (location.VerticalAccuracy > -1)
{
p.Altitude = location.Altitude;
p.AltitudeAccuracy = location.VerticalAccuracy;
}
if (location.Speed > -1)
p.Speed = location.Speed;
var dateTime = location.Timestamp.ToDateTime().ToUniversalTime();
p.Timestamp = new DateTimeOffset (dateTime);
this.position = p;
OnPositionChanged (new PositionEventArgs (p));
location.Dispose();
}
private void Finish(Location location)
{
var p = new Position();
if (location.HasAccuracy)
p.Accuracy = location.Accuracy;
if (location.HasAltitude)
p.Altitude = location.Altitude;
if (location.HasBearing)
p.Heading = location.Bearing;
if (location.HasSpeed)
p.Speed = location.Speed;
p.Longitude = location.Longitude;
p.Latitude = location.Latitude;
p.Timestamp = GeolocatorImplementation.GetTimestamp(location);
if (this.finishedCallback != null)
this.finishedCallback();
this.completionSource.TrySetResult(p);
}
public override void ResetForSharing()
{
base.ResetForSharing();
_previousPosition = null;
}
private static Position GetPosition(Geoposition position)
{
var pos = new Position
{
Accuracy = position.Coordinate.Accuracy,
Latitude = position.Coordinate.Point.Position.Latitude,
Longitude = position.Coordinate.Point.Position.Longitude,
Timestamp = position.Coordinate.Timestamp.ToUniversalTime(),
};
if (position.Coordinate.Heading != null)
pos.Heading = position.Coordinate.Heading.Value;
if (position.Coordinate.Speed != null)
pos.Speed = position.Coordinate.Speed.Value;
if (position.Coordinate.AltitudeAccuracy.HasValue)
pos.AltitudeAccuracy = position.Coordinate.AltitudeAccuracy.Value;
pos.Altitude = position.Coordinate.Point.Position.Altitude;
return pos;
}
private void OnUpdatedHeading (object sender, CLHeadingUpdatedEventArgs e)
{
if (e.NewHeading.TrueHeading == -1)
return;
Position p = (this.position == null) ? new Position () : new Position (this.position);
p.Heading = e.NewHeading.TrueHeading;
this.position = p;
OnPositionChanged (new PositionEventArgs (p));
}
protected override IEnumerable<Datum> Poll(CancellationToken cancellationToken)
{
lock (_locker)
{
SpeedDatum datum = null;
Position currentPosition = GpsReceiver.Get().GetReading(cancellationToken);
if (currentPosition == null)
throw new Exception("Failed to get GPS reading.");
else
{
if (_previousPosition == null)
_previousPosition = currentPosition;
else if (currentPosition.Timestamp > _previousPosition.Timestamp) // it has happened (rarely) that positions come in out of order...drop any such positions.
{
datum = new SpeedDatum(currentPosition.Timestamp, _previousPosition, currentPosition);
_previousPosition = currentPosition;
}
}
if (datum == null)
return new Datum[] { }; // datum will be null on the first poll and where polls return locations out of order (rare). these should count toward participation.
else
return new Datum[] { datum };
}
}
public PositionEventArgs(Position position)
{
if (position == null)
throw new ArgumentNullException("position");
Position = position;
}
public static double CalculateSpeedKPH(Position previousPosition, Position currentPosition, out double distanceKM, out double timeHours)
{
distanceKM = CalculateDistanceKM(previousPosition, currentPosition);
timeHours = new TimeSpan(currentPosition.Timestamp.Ticks - previousPosition.Timestamp.Ticks).TotalHours;
return distanceKM / timeHours;
}
/// <inheritdoc/>
private void OnListenerPositionChanged(object sender, PositionEventArgs e)
{
if (!IsListening) // ignore anything that might come in afterwards
return;
lock (positionSync)
{
lastPosition = e.Position;
var changed = PositionChanged;
if (changed != null)
changed(this, e);
}
}
public GetGeoCS()
{
button = new Button
{
Text = "Get Geolocator"
};
button.Clicked += async (sender, e) =>
{
IGeolocator locator = CrossGeolocator.Current;
locator.DesiredAccuracy = 50;
if (locator.IsGeolocationAvailable)
{
if (locator.IsGeolocationEnabled)
{
try
{
position = await locator.GetPositionAsync(timeoutMilliseconds: 10000);
latLabel.Text = "Latitude: " + position.Latitude;
lonLabel.Text = "Longitude: " + position.Longitude;
System.Diagnostics.Debug.WriteLine("TimeStamp: " + position.Timestamp);
}
catch (GeolocationException ex)
{
System.Diagnostics.Debug.WriteLine(ex.InnerException);
await DisplayAlert("Error", "Unauthorized", "OK");
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine(ex.InnerException);
}
}
else
await DisplayAlert("Error", "Geo sensors is not turned on.\nPlease turn on it.", "OK");
}
else
await DisplayAlert("Error", "This device does not have any geo sensors or enough permission to use it.", "OK");
};
latLabel = new Label
{
Text = "Latitude: "
};
lonLabel = new Label
{
Text = "Longitude: "
};
Content = new StackLayout
{
Padding = new Thickness(10, Device.OnPlatform(20, 0, 0), 10, 10),
Children = {
button,
latLabel,
lonLabel
}
};
}
