/// <summary>
        /// Removes a given SannerDataItem from the scanner information list
        /// </summary>
        /// <param name="removedScannerInfo">ScannerDataItem that is to be removed from the list </param>
        private void  RemoveFromList(ScannerDataItem removedScannerInfo)
        {
            // If currently selected scanner is being removed, make sure
            // to select a different one
            if (currentScannerDeviceId == removedScannerInfo.Id)
            {
                String scannerIdToSelect = (scannerInfoList.Count == 0) ?
                                           null :
                                           scannerInfoList.ElementAt(0).Id;

                ChangeCurrentlySelectedScanner(scannerIdToSelect);
            }
            scannerInfoList.Remove(removedScannerInfo);
            OnPropertyChanged("ScannerListSize");
        }
        /// <summary>
        /// Event handler a scanner being added
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="deviceInfo">The device info for the device which was added</param>
        private async void OnScannerAdded(DeviceWatcher sender, DeviceInformation deviceInfo)
        {
            await
            MainPage.Current.Dispatcher.RunAsync(
                Windows.UI.Core.CoreDispatcherPriority.Normal,
                () =>
            {
                MainPage.Current.NotifyUser(String.Format("Scanner with device id {0} has been added", deviceInfo.Id), NotifyType.StatusMessage);

                // search the device list for a device with a matching device id
                ScannerDataItem match = FindInList(deviceInfo.Id);

                // If we found a match then mark it as verified and return
                if (match != null)
                {
                    match.Matched = true;
                    return;
                }

                // Add the new element to the end of the list of devices
                AppendToList(deviceInfo);
            }
                );
        }
        /// <summary>
        /// Removes a given SannerDataItem from the scanner information list 
        /// </summary>
        /// <param name="removedScannerInfo">ScannerDataItem that is to be removed from the list </param>
        private  void  RemoveFromList(ScannerDataItem removedScannerInfo)
        {

            // If currently selected scanner is being removed, make sure
            // to select a different one
            if (currentScannerDeviceId == removedScannerInfo.Id) 
            {
                String scannerIdToSelect = (scannerInfoList.Count == 0) ? 
                                             null :
                                             scannerInfoList.ElementAt(0).Id;

                ChangeCurrentlySelectedScanner(scannerIdToSelect);
            }
            scannerInfoList.Remove(removedScannerInfo);
            OnPropertyChanged("ScannerListSize");
        }