scan_bloc.dart

import 'dart:async';
import 'dart:ui';

import 'package:scandit_flutter_datacapture_barcode/scandit_flutter_datacapture_barcode.dart';
import 'package:scandit_flutter_datacapture_barcode/scandit_flutter_datacapture_barcode_capture.dart';
import 'package:scandit_flutter_datacapture_core/scandit_flutter_datacapture_core.dart';

const String licenseKey = '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';

class ScanBloc implements BarcodeCaptureListener {
  final DataCaptureContext _captureContext = DataCaptureContext.forLicenseKey(licenseKey);

  late BarcodeCapture _barcodeCapture;

  Camera? _camera = Camera.defaultCamera;

  late DataCaptureView _captureView;

  StreamController<String> _singleScanResultController = StreamController();

  Stream<String> get singleScanResult => _singleScanResultController.stream;

  ScanBloc() {
    _init();
  }

  void _init() {
    _camera?.applySettings(BarcodeCapture.recommendedCameraSettings);

    _captureView = DataCaptureView.forContext(_captureContext);
    _barcodeCapture = BarcodeCapture.forContext(_captureContext, barcodeCaptureSettings)
      ..addListener(this);

    // 照準とバーコード読取時のオーバーレイを設定
    var overlay = BarcodeCaptureOverlay.withBarcodeCaptureForViewWithStyle(
        _barcodeCapture, _captureView, BarcodeCaptureOverlayStyle.frame)
      ..viewfinder = RectangularViewfinder.withStyle(RectangularViewfinderStyle.square);
    overlay.brush = Brush(Color.fromARGB(0, 0, 0, 0), Color.fromARGB(255, 255, 255, 255), 3);
    _captureView.addOverlay(overlay);

    // ズーム切替ボタンを追加
    _captureView.addControl(ZoomSwitchControl());
    // ライト切替ボタンを追加
    _captureView.addControl(TorchSwitchControl());

    if (_camera != null) {
      _captureContext.setFrameSource(_camera!);
    }
    enableBarcodeCapture();
  }

  BarcodeCaptureSettings get barcodeCaptureSettings {
    var captureSettings = BarcodeCaptureSettings();
    //必要に応じてシンボルを有効化して下さい
    //記載されていないシンボルを有効化したい場合は、以下を参照してください
    //https://docs.scandit.com/data-capture-sdk/flutter/barcode-capture/api/symbology.html
    captureSettings.enableSymbologies({
      // Symbology.ean8,
      Symbology.ean13Upca,
      // Symbology.upce,
      // Symbology.qr,
      // Symbology.dataMatrix,
      // Symbology.code39,
      // Symbology.code128,
      // Symbology.interleavedTwoOfFive
    });

    //厳格（strict）モードを有効化
    // https://docs.scandit.com/data-capture-sdk/flutter/barcode-capture/symbology-properties.html#symbology-extension-descriptions
    var symbologySettings = captureSettings.settingsForSymbology(Symbology.ean13Upca);
    symbologySettings.setExtensionEnabled("strict", enabled: true);

    // 選択領域を設定
    // https://docs.scandit.com/data-capture-sdk/flutter/advanced-topics.html#rectangular-location-selection
    captureSettings.locationSelection = RectangularLocationSelection.withSize(SizeWithUnit(
      DoubleWithUnit(0.7, MeasureUnit.fraction),
      DoubleWithUnit(0.3, MeasureUnit.fraction)));

    return captureSettings;
  }

  DataCaptureView get captureView => _captureView;

  void enableBarcodeCapture() {
    switchCameraOn();
    _barcodeCapture.isEnabled = true;
  }

  void disableBarcodeCapture() {
    _barcodeCapture.isEnabled = false;
    switchCameraStandby();
  }

  void switchCameraOff() {
    _camera?.switchToDesiredState(FrameSourceState.off);
  }

  void switchCameraOn() {
    _camera?.switchToDesiredState(FrameSourceState.on);
  }

  void switchCameraStandby() {
    _camera?.switchToDesiredState(FrameSourceState.standby);
  }

  void dispose() {
    _barcodeCapture.removeListener(this);
    disableBarcodeCapture();
    switchCameraOff();
    _singleScanResultController.close();
  }

  @override
  void didScan(BarcodeCapture barcodeCapture, BarcodeCaptureSession session) {
    disableBarcodeCapture();
    // 読み取ったバーコードの値を通知
    var code = session.newlyRecognizedBarcodes[0];
    var data = (code.data == null || code.data?.isEmpty == true) ? code.rawData : code.data;
    _singleScanResultController.sink.add(data!);
  }

  @override
  void didUpdateSession(BarcodeCapture barcodeCapture, BarcodeCaptureSession session) {
  }
}