Flutter

Multiple Barcode Scanning

Multiple Barcode Scanning is a mode in the Vision SDK that allows you to scan and detect multiple barcodes within the camera frame simultaneously. This is useful in scenarios where several barcodes are present in a single image or view, and you want to capture all of them in one go.

Unlike single barcode scanning, this mode does not restrict detection to just one barcode. Instead, it returns an array of all valid barcodes detected within the scanning region, improving efficiency for batch processing or document scanning use cases.

⚙️ Setting Multiple Barcode Scanning

To enable single barcode scanning, you need to call the following method from FlutterToPluginCommunicator:

        class VisionSDKStatelessWidget extends StatelessWidget {
  const VisionSDKStatelessWidget({super.key, required this.listener});

  final PluginToFlutterCommunicator listener;

  @override
  Widget build(BuildContext context) {
    return VisionCameraWidget(
      listener: listener,
      onViewCreated: (FlutterToPluginCommunicator sender) {
        sender.setCaptureModeBarcode();
        sender.setMultipleScanEnabled(true);
        sender.startCamera();
      },
    );
  }
}

Select the camera lens you want to use for barcode scanning:

        sender.setCameraSettings(CameraSettings(cameraLensFace: CameraLensFace.back));

🤖 Auto Mode Barcode Scanning

For automatic barcode capture, call the following method:

        sender.setScanAuto();

✋ Manual Mode Barcode Scanning

For manual barcode capture, call the following method:

        sender.setScanManual();

Afterwards, when you want to capture, call the following method:

        sender.capturePhoto();

📦 Callback Method for Barcode Values

When a barcode is successfully scanned, the following callback method is called:

        class Listener implements PluginToFlutterCommunicator {
  @override
  void onCodesReceived(List<ScannedCodeResult> scannedCodeResults) {
    
  }
}

Note that, once onCodesReceived or onImageCaptured callbacks are called, VisionSDK will stop analyzing camera feed for text or barcodes/QR codes. This is to prevent extra processing and battery consumption. When client wants to start analyzing camera feed again, after consuming the results of previous scan, client needs to call the following function:

        sender.rescan()

❗️Error Handling Callback

If an error occurs during the barcode scanning process, the following callback method will be triggered. You can implement this to handle any failures during scanning, gracefully.

        class Listener implements PluginToFlutterCommunicator {
  @override
  void onScanError(String error) {
    
  }
}

Use this method to log errors, display messages to the user, or perform recovery actions when scanning fails.

🧾 Barcode Object Structure

The ScannedCodeResult object returned in the callback contains the following properties:

        class ScannedCodeResult {
  final String scannedCode;
  final BarcodeSymbology symbology;
  final Map<String, String>? gs1ExtractedInfo;
}

🧭 Detection Indicators

To receive detection indicators (without actual values), implement the following callback method:

        class Listener implements PluginToFlutterCommunicator {
  @override
  void onDetectionResult(bool isText, bool isBarcode, bool isQrCode, bool isDocument) {
    
  }
}

isText: Indicates presence of text
isBarcode: Indicates presence of a barcode
isQrCode: Indicates presence of a QR code
isDocument: Indicates presence of a document

🔘 Enable Detection Indicators

You can toggle detection indicators as follows:

        class VisionSDKStatelessWidget extends StatelessWidget {
  const VisionSDKStatelessWidget({super.key, required this.listener});

  final PluginToFlutterCommunicator listener;

  @override
  Widget build(BuildContext context) {
    return VisionCameraWidget(
      listener: listener,
      onViewCreated: (FlutterToPluginCommunicator sender) {
        sender.setObjectDetectionSettings(
          ObjectDetectionSettings(
            isTextIndicationOn: true,
            isBarcodeOrQRCodeIndicationOn: true,
            isDocumentIndicationOn: true
          )
        );
      },
    );
  }
}

🧪 Sample Code

To start scanning for barcodes, QR codes, text or documents, use the startCamera method. See the code below for example:

        class VisionSDKStatelessWidget extends StatelessWidget {
  const VisionSDKStatelessWidget({super.key, required this.listener});

  final PluginToFlutterCommunicator listener;

  @override
  Widget build(BuildContext context) {
    return VisionCameraWidget(
      listener: listener,
      onViewCreated: (FlutterToPluginCommunicator sender) {
        sender.setCaptureModeBarcode();
        sender.setMultipleScanEnabled(true);
        sender.setCameraSettings(CameraSettings(cameraLensFace: CameraLensFace.back));
        sender.setScanAuto();
        sender.setObjectDetectionSettings(
          ObjectDetectionSettings(
            isTextIndicationOn: true,
            isBarcodeOrQRCodeIndicationOn: true,
            isDocumentIndicationOn: true
          )
        );
        sender.startCamera();
      },
    );
  }
}

class Listener implements PluginToFlutterCommunicator {
  @override void onCameraStarted() {}
  @override void onCameraStopped() {}
  @override void onCodesReceived(List<ScannedCodeResult> scannedCodeResults) {}
  @override void onDetectionResult(bool isText, bool isBarcode, bool isQrCode, bool isDocument) {}
  @override void onImageCaptured(Uint8List byteArrayImage, List<ScannedCodeResult> scannedCodeResults) {}
  @override void onMatchingResult(Map<String, dynamic> result) {}
  @override void onOnlineBOLResult(Map<String, dynamic> result) {}
  @override void onOnlineDocumentClassificationResult(Map<String, dynamic> result) {}
  @override void onOnlineItemLabelResult(Map<String, dynamic> result) {}
  @override void onOnlineSLResult(Map<String, dynamic> result) {}
  @override void onScanError(String error) {}
}

Multiple Barcode Scanning

# ⚙️ Setting Multiple Barcode Scanning

# 🤖 Auto Mode Barcode Scanning

# ✋ Manual Mode Barcode Scanning

# 📦 Callback Method for Barcode Values

# ❗️Error Handling Callback

# 🧾 Barcode Object Structure

# 🧭 Detection Indicators

# 🔘 Enable Detection Indicators

# 🧪 Sample Code

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