My Experience with the Windows Marketplace for Mobile and Windows Mobile 6

using System;
using System.Linq;
using System.Collections.Generic;
using System.Text;
using SpeedTracker.Common;
using SpeedTracker.Converters;
using SpeedTracker.Gps;



namespace SpeedTracker
{
    class GpsLocationProvider : ILocationProvider
    {
        private const string ProviderName = "GPSID Provider";
        private GpsId _gpsId;

        private bool _hasFix = false;
        private bool _isActive = false;
        private int _fixQuality = 0;
        private IValueConverter _speedConverter=null;

        private Location _lastLocation = new Location();
        public object SyncRoot = new object();
        public GpsLocationProvider()
        {
            _speedConverter = SpeedTracker.Converters.ConverterCatalog.GetConverter(new ConversionUnitNames("nautical mile", "kilometer"));
        }

        #region ILocationProvider Members

        public string Name
        {
            get { return ProviderName; }
        }

        public event EventHandler<LocationUpdatedEventArgs> LocationUpdated;

        protected void OnLocationUpdated(Location newLocation)
        {
            if (LocationUpdated != null)
            lock (SyncRoot)
            {
                if (LocationUpdated != null)
                {
                    LocationUpdated(this, new LocationUpdatedEventArgs() {NewLocation = newLocation});
                }
            }
        }

        public bool IsActive
        {
            get { return _isActive; }
        }

        public bool HasFix
        {
            get { return _hasFix; }
        }

        public Location LastLocation
        {
            get { return _lastLocation; }
        }

        public void Start()
        {
            if(_gpsId==null)
            {
                _gpsId = new GpsId();
                _gpsId.LocationChanged += new LocationChangedEventHandler(gpsId_LocationChanged);
                _gpsId.DeviceStateChanged += new DeviceStateChangedEventHandler(_gpsId_DeviceStateChanged);
            }
            if(_gpsId!=null)
            {
                _gpsId.Open();
                _isActive = true;
            }
        }

        void _gpsId_DeviceStateChanged(object sender, DeviceStateChangedEventArgs args)
        {
            
        }


        void gpsId_LocationChanged(object sender, LocationChangedEventArgs args)
        {
            if(!_isActive)
                return;
            Location newLoc = new Location() {TimeStamp = DateTime.MinValue};
            newLoc.IsLocationValid  = _hasFix = (args.Position != null) && (args.Position.LongitudeValid && args.Position.LongitudeValid);
            if (_hasFix)
            {
                newLoc.Latitude = args.Position.Latitude;
                newLoc.Longitude = args.Position.Longitude;
                newLoc.Speed =
                    (float) (double) _speedConverter.Convert((double)args.Position.Speed, typeof (double), null, null);
                newLoc.Heading = args.Position.Heading;
                newLoc.TimeStamp = args.Position.Time;
            }
            this._lastLocation = newLoc;

            OnLocationUpdated(newLoc);

        }

        public void Stop()
        {
            if (_gpsId != null)
            {
                _gpsId.Close();
                _gpsId.LocationChanged -= (gpsId_LocationChanged);
                _gpsId.DeviceStateChanged -= (_gpsId_DeviceStateChanged);
            }
            _isActive = false;
            _hasFix = false;
        }

        #endregion

        #region IDisposable Members

        public void Dispose()
        {

        }

        #endregion
    }
}