static async Task <BarcodeScanner> FindBarcodeScannerAsync()
{
BarcodeScanner locatedScanner = null;
if (CachedBarcodeDeviceId == null)
{
// NB: changed to 'local' here in the hope of speeding up this call as
// it seems to take a long time.
var deviceSelector = BarcodeScanner.GetDeviceSelector(
PosConnectionTypes.Local);
var devices = await DeviceInformation.FindAllAsync(deviceSelector);
if (devices != null)
{
foreach (var device in devices)
{
var scanner = await BarcodeScanner.FromIdAsync(device.Id);
if (scanner.VideoDeviceId != null)
{
CachedBarcodeDeviceId = device.Id;
break;
}
}
}
}
if (CachedBarcodeDeviceId != null)
{
locatedScanner = await BarcodeScanner.FromIdAsync(CachedBarcodeDeviceId);
}
return(locatedScanner);
}
async Task <bool> CreateDeviceList_OneTime(Type[] deviceClasses)
{
foreach (Type ty in deviceClasses)
{
DeviceInformationCollection deviceList = null;
if (ty == typeof(BarcodeScanner))
{
deviceList = await DeviceInformation.FindAllAsync(BarcodeScanner.GetDeviceSelector());
}
else if (ty == typeof(PosPrinter))
{
deviceList = await DeviceInformation.FindAllAsync(PosPrinter.GetDeviceSelector());
}
else if (ty == typeof(CashDrawer))
{
deviceList = await DeviceInformation.FindAllAsync(CashDrawer.GetDeviceSelector());
}
else if (ty == typeof(MagneticStripeReader))
{
deviceList = await DeviceInformation.FindAllAsync(MagneticStripeReader.GetDeviceSelector());
}
else if (ty == typeof(LineDisplay))
{
deviceList = await DeviceInformation.FindAllAsync(LineDisplay.GetDeviceSelector());
}
AddToSelectionList(ty, deviceList);
}
return(true);
}
private async void OnInitializeScannerAsync()
{
string selector = BarcodeScanner.GetDeviceSelector(PosConnectionTypes.Local);
DeviceInformationCollection deviceCollection = await DeviceInformation.FindAllAsync(selector);
foreach (var device in deviceCollection)
{
BarcodeScanner scanner = await BarcodeScanner.FromIdAsync(device.Id);
if (scanner != null && scanner.VideoDeviceId != null)
{
_claimedScanner = await scanner.ClaimScannerAsync();
if (_claimedScanner != null)
{
await _claimedScanner.EnableAsync();
_claimedScanner.DataReceived += OnBarcodeDetected;
await _videoPreview.StartStreamingAsync(scanner.VideoDeviceId);
await _claimedScanner.StartSoftwareTriggerAsync();
break;
}
}
}
}
/// <summary>
/// Start device watcher.
/// </summary>
public void StartWatcher(CoreDispatcher dispatcher)
{
if (posDeviceWatcher == null)
{
posDeviceWatcher = new PosDeviceWatcher(BarcodeScanner.GetDeviceSelector(), dispatcher);
posDeviceWatcher.Start();
}
}
/// <summary>
/// Start device watcher.
/// </summary>
private void StartWatcher()
{
if (posDeviceWatcher == null)
{
posDeviceWatcher = new PosDeviceWatcher(BarcodeScanner.GetDeviceSelector(), Dispatcher);
posDeviceWatcher.Start();
}
}
internal async Task StartScannerAsync()
{
capturePreview.Visibility = Visibility.Visible;
capturePreview.Width = 400; capturePreview.Height = 300;
scanner = await DeviceHelpers.GetFirstDeviceAsync(BarcodeScanner.GetDeviceSelector(), async (id) => await BarcodeScanner.FromIdAsync(id));
if (scanner != null)
{
claimedScanner = await scanner.ClaimScannerAsync();
if (claimedScanner != null)
{
claimedScanner.ReleaseDeviceRequested += ClaimedScanner_ReleaseDeviceRequested;
claimedScanner.DataReceived += ClaimedScanner_DataReceived;
claimedScanner.IsDecodeDataEnabled = true;
await claimedScanner.EnableAsync();
try
{
bool haveAssociatedCamera = !string.IsNullOrEmpty(scanner.VideoDeviceId);
if (haveAssociatedCamera)
{
captureManager = new MediaCapture();
captureManager.Failed += CaptureManager_Failed;
MediaCaptureInitializationSettings _captureInitSettings = new MediaCaptureInitializationSettings
{
VideoDeviceId = scanner.VideoDeviceId,
SharingMode = MediaCaptureSharingMode.SharedReadOnly, // share
StreamingCaptureMode = StreamingCaptureMode.Video // just video
};
await captureManager.InitializeAsync(_captureInitSettings);
capturePreview.Source = captureManager;
}
UpdateMessage("waiting..." + (!haveAssociatedCamera ? "But scanner not camera type" : ""));
if (captureManager != null) await captureManager.StartPreviewAsync();
await claimedScanner.StartSoftwareTriggerAsync();
}
catch (Exception e)
{
UpdateMessage(e.Message);
Debug.WriteLine("EXCEPTION: " + e.Message);
}
}
else
{
UpdateMessage("Could not claim barcode scanner");
}
}
else
{
UpdateMessage("No barcode scanners found");
}
}
public Scenario5_DisplayingBarcodePreview()
{
this.InitializeComponent();
ScannerListSource.Source = barcodeScanners;
watcher = DeviceInformation.CreateWatcher(BarcodeScanner.GetDeviceSelector());
watcher.Added += Watcher_Added;
watcher.Removed += Watcher_Removed;
watcher.Updated += Watcher_Updated;
watcher.Start();
DataContext = this;
}
private static string GetPosSelector(Type ty)
{
if (ty == typeof(BarcodeScanner))
{
return(BarcodeScanner.GetDeviceSelector());
}
if (ty == typeof(PosPrinter))
{
return(PosPrinter.GetDeviceSelector());
}
if (ty == typeof(CashDrawer))
{
return(CashDrawer.GetDeviceSelector());
}
if (ty == typeof(MagneticStripeReader))
{
return(MagneticStripeReader.GetDeviceSelector());
}
if (ty == typeof(LineDisplay))
{
return(LineDisplay.GetDeviceSelector());
}
return(null);
}
private async void CodeScanner_Loaded(object sender, RoutedEventArgs e)
{
BarcodeList.ItemsSource = BarcodeHistory = new ObservableCollection <BarcodeItem>();
ExitLocker = new AutoResetEvent(false);
string Selector = BarcodeScanner.GetDeviceSelector(PosConnectionTypes.Local);
DeviceInformationCollection DeviceCollection = await DeviceInformation.FindAllAsync(Selector);
if (DeviceCollection == null || DeviceCollection.Count == 0)
{
Pro.Visibility = Visibility.Collapsed;
ProText.Text = "无摄像头可用";
return;
}
if (ApplicationData.Current.LocalSettings.Values["LastSelectedCameraSource"] is string StorageCameraSource)
{
foreach (var DeviceID in from Device in DeviceCollection
where Device.Name.Contains(StorageCameraSource)
select Device.Id)
{
using (BarcodeScanner Scanner = await BarcodeScanner.FromIdAsync(DeviceID))
{
Capture = new MediaCapture();
var InitializeSettings = new MediaCaptureInitializationSettings
{
VideoDeviceId = Scanner.VideoDeviceId,
StreamingCaptureMode = StreamingCaptureMode.Video,
PhotoCaptureSource = PhotoCaptureSource.VideoPreview
};
await Capture.InitializeAsync(InitializeSettings);
var CameraFocusControl = Capture.VideoDeviceController.FocusControl;
if (CameraFocusControl.Supported)
{
await CameraFocusControl.UnlockAsync();
CameraFocusControl.Configure(new FocusSettings {
Mode = FocusMode.Continuous, AutoFocusRange = AutoFocusRange.FullRange
});
await CameraFocusControl.FocusAsync();
}
PreviewControl.Source = Capture;
ClaimedScanner = await Scanner.ClaimScannerAsync();
ClaimedScanner.IsDisabledOnDataReceived = false;
ClaimedScanner.IsDecodeDataEnabled = true;
ClaimedScanner.DataReceived += ClaimedScanner_DataReceived;
await ClaimedScanner.EnableAsync();
await ClaimedScanner.StartSoftwareTriggerAsync();
await Capture.StartPreviewAsync();
}
break;
}
if (Capture == null)
{
ContentDialog dialog = new ContentDialog
{
Title = "提示",
Content = " 设置所指定的摄像头无法应用于条码识别\r\r 已自动选择最合适的摄像头",
CloseButtonText = "确定",
Background = Application.Current.Resources["DialogAcrylicBrush"] as Brush
};
_ = await dialog.ShowAsync();
using (BarcodeScanner Scanner = await BarcodeScanner.FromIdAsync(DeviceCollection.FirstOrDefault().Id))
{
Capture = new MediaCapture();
var InitializeSettings = new MediaCaptureInitializationSettings
{
VideoDeviceId = Scanner.VideoDeviceId,
StreamingCaptureMode = StreamingCaptureMode.Video,
PhotoCaptureSource = PhotoCaptureSource.VideoPreview
};
await Capture.InitializeAsync(InitializeSettings);
var CameraFocusControl = Capture.VideoDeviceController.FocusControl;
if (CameraFocusControl.Supported)
{
await CameraFocusControl.UnlockAsync();
CameraFocusControl.Configure(new FocusSettings {
Mode = FocusMode.Continuous, AutoFocusRange = AutoFocusRange.FullRange
});
await CameraFocusControl.FocusAsync();
}
PreviewControl.Source = Capture;
ClaimedScanner = await Scanner.ClaimScannerAsync();
ClaimedScanner.IsDisabledOnDataReceived = false;
ClaimedScanner.IsDecodeDataEnabled = true;
ClaimedScanner.DataReceived += ClaimedScanner_DataReceived;
await ClaimedScanner.EnableAsync();
await ClaimedScanner.StartSoftwareTriggerAsync();
await Capture.StartPreviewAsync();
}
}
}
else
{
using (BarcodeScanner Scanner = await BarcodeScanner.FromIdAsync(DeviceCollection.FirstOrDefault().Id))
{
Capture = new MediaCapture();
var InitializeSettings = new MediaCaptureInitializationSettings
{
VideoDeviceId = Scanner.VideoDeviceId,
StreamingCaptureMode = StreamingCaptureMode.Video,
PhotoCaptureSource = PhotoCaptureSource.VideoPreview
};
await Capture.InitializeAsync(InitializeSettings);
var CameraFocusControl = Capture.VideoDeviceController.FocusControl;
if (CameraFocusControl.Supported)
{
await CameraFocusControl.UnlockAsync();
CameraFocusControl.Configure(new FocusSettings {
Mode = FocusMode.Continuous, AutoFocusRange = AutoFocusRange.FullRange
});
await CameraFocusControl.FocusAsync();
}
PreviewControl.Source = Capture;
ClaimedScanner = await Scanner.ClaimScannerAsync();
ClaimedScanner.IsDisabledOnDataReceived = false;
ClaimedScanner.IsDecodeDataEnabled = true;
ClaimedScanner.DataReceived += ClaimedScanner_DataReceived;
await ClaimedScanner.EnableAsync();
await ClaimedScanner.StartSoftwareTriggerAsync();
await Capture.StartPreviewAsync();
}
}
LoadingControl.IsLoading = false;
ExitLocker.Set();
}
public static async Task <BarcodeScanner> GetFirstBarcodeScannerAsync(PosConnectionTypes connectionTypes = PosConnectionTypes.All)
{
return(await DeviceHelpers.GetFirstDeviceAsync(BarcodeScanner.GetDeviceSelector(connectionTypes), async (id) => await BarcodeScanner.FromIdAsync(id)));
}
/// <summary>
/// Creates the default barcode scanner.
/// </summary>
/// <returns>true if barcode scanner is created. Otherwise returns false</returns>
private async Task <bool> CreateDefaultScannerObject()
{
if (scanner == null)
{
rootPage.NotifyUser("Creating barcode scanner object.", NotifyType.StatusMessage);
DeviceInformationCollection deviceCollection = await DeviceInformation.FindAllAsync(BarcodeScanner.GetDeviceSelector());
if (deviceCollection != null && deviceCollection.Count > 0)
{
scanner = await BarcodeScanner.FromIdAsync(deviceCollection[0].Id);
if (scanner == null)
{
rootPage.NotifyUser("Failed to create barcode scanner object.", NotifyType.ErrorMessage);
return(false);
}
}
else
{
rootPage.NotifyUser("Barcode scanner not found. Please connect a barcode scanner.", NotifyType.ErrorMessage);
return(false);
}
}
return(true);
}
public static async Task <BarcodeScanner> GetFirstBarcodeScannerAsync()
{
return(await DeviceHelpers.GetFirstDeviceAsync(BarcodeScanner.GetDeviceSelector(), async (id) => await BarcodeScanner.FromIdAsync(id)));
}
