public void LoadConfiguration()
        {
            try
            {
                var filename = GetConfigFilename();

                if (string.IsNullOrWhiteSpace(filename) || !File.Exists(filename))
                {
                    return;
                }

                XmlSerializer x  = new XmlSerializer(GetType());
                TextReader    tr = new StreamReader(filename);

                CoordinateConversionLibraryConfig temp = null;
                try
                {
                    temp = x.Deserialize(tr) as CoordinateConversionLibraryConfig;
                }
                catch
                {
                    /* Deserialize Failed */
                }
                finally
                {
                    tr.Close();
                }

                if (temp == null)
                {
                    return;
                }

                //DisplayCoordinateType = temp.DisplayCoordinateType;
                DisplayAmbiguousCoordsDlg    = temp.DisplayAmbiguousCoordsDlg;
                OutputCoordinateList         = temp.OutputCoordinateList;
                DefaultFormatList            = temp.DefaultFormatList;
                ShowPlusForDirection         = temp.ShowPlusForDirection;
                ShowHyphenForDirection       = temp.ShowHyphenForDirection;
                IsHemisphereIndicatorChecked = temp.IsHemisphereIndicatorChecked;
                IsPlusHyphenChecked          = temp.IsPlusHyphenChecked;
                IsHemisphereIndicatorChecked = temp.IsHemisphereIndicatorChecked;

                RaisePropertyChanged(() => IsPlusHyphenChecked);
                RaisePropertyChanged(() => IsHemisphereIndicatorChecked);
                RaisePropertyChanged(() => ShowPlusForDirection);
                RaisePropertyChanged(() => ShowHyphenForDirection);
                RaisePropertyChanged(() => OutputCoordinateList);
                RaisePropertyChanged(() => DefaultFormatList);
            }
            catch (Exception ex)
            {
                System.Diagnostics.Debug.WriteLine(ex.Message);
            }
        }
        public override void OnDisplayCoordinateTypeChanged(CoordinateConversionLibrary.Models.CoordinateConversionLibraryConfig obj)
        {
            base.OnDisplayCoordinateTypeChanged(obj);

            // update list box coordinates
            var list = CoordinateAddInPoints.ToList();

            CoordinateAddInPoints.Clear();
            foreach (var item in list)
            {
                CoordinateAddInPoints.Add(item);
            }
        }