mymuseum-visitapp/lib/Components/ScannerDialog.dart

import 'package:flutter/material.dart';
import 'dart:io';
import 'package:flutter/foundation.dart';
import 'package:mymuseum_visitapp/Helpers/translationHelper.dart';
import 'package:mymuseum_visitapp/Models/visitContext.dart';
import 'package:mymuseum_visitapp/Screens/Article/article_page.dart';
import 'package:mymuseum_visitapp/app_context.dart';
import 'package:mymuseum_visitapp/constants.dart';
import 'package:qr_code_scanner/qr_code_scanner.dart';


class ScannerDialog extends StatefulWidget {
  const ScannerDialog({Key? key, required this.appContext}) : super(key: key);

  final AppContext? appContext;

  @override
  State<ScannerDialog> createState() => _ScannerDialogState();
}

class _ScannerDialogState extends State<ScannerDialog> {
  Barcode? result;
  QRViewController? controller;
  final GlobalKey qrKey = GlobalKey(debugLabel: 'QR');

  // In order to get hot reload to work we need to pause the camera if the platform
  // is android, or resume the camera if the platform is iOS.
  @override
  void reassemble() {
    super.reassemble();
    if (Platform.isAndroid) {
      controller!.pauseCamera();
    }
    controller!.resumeCamera();
  }

  @override
  Widget build(BuildContext context) {
    Size size = MediaQuery.of(context).size;
    return Container(
      height: size.height *0.5,
      width: size.width *0.9,
      child: Stack(
        children: [
          Center(
            child: ClipRRect(
              borderRadius: BorderRadius.circular(10.0),
              child: _buildQrView(context),
            )
          ),
          Positioned(
            top: 0,
            right: 0,
            child: Container(
              width: 45,
              height: 45,
              decoration: BoxDecoration(
                shape: BoxShape.rectangle,
                color: kBlue1,
                borderRadius: BorderRadius.circular(20.0),
              ),
              margin: const EdgeInsets.all(8),
              child: InkWell(
                  onTap: () async {
                    await controller?.toggleFlash();
                    setState(() {});
                  },
                  child: FutureBuilder(
                    future: controller?.getFlashStatus(),
                    builder: (context, snapshot) {
                      return const Icon(Icons.flash_on, color: Colors.white);
                    },
                  )),
            ),
          ),
          Positioned(
            bottom: 0,
            right: 0,
            child: Container(
              width: 45,
              height: 45,
              decoration: BoxDecoration(
                shape: BoxShape.rectangle,
                color: kBlue1,
                borderRadius: BorderRadius.circular(20.0),
              ),
              margin: const EdgeInsets.all(8),
              child: InkWell(
                  onTap: () async {
                    await controller?.flipCamera();
                    setState(() {});
                  },
                  child: FutureBuilder(
                    future: controller?.getCameraInfo(),
                    builder: (context, snapshot) {
                      return const Icon(Icons.flip_camera_android, color: Colors.white);
                    },
                  )),
            ),
          ),
        ],
      ),
    );
  }

  Widget _buildQrView(BuildContext context) {
    // For this example we check how width or tall the device is and change the scanArea and overlay accordingly.
    var scanArea = (MediaQuery.of(context).size.width < 400 ||
        MediaQuery.of(context).size.height < 400)
        ? 225.0
        : 300.0;

    // To ensure the Scanner view is properly sizes after rotation
    // we need to listen for Flutter SizeChanged notification and update controller
    return QRView(
      key: qrKey,
      onQRViewCreated: _onQRViewCreated,
      overlay: QrScannerOverlayShape(
          borderColor: kBlue1,
          borderRadius: 10,
          borderLength: 25,
          borderWidth: 5,
          cutOutSize: 225.0),
      onPermissionSet: (ctrl, p) => _onPermissionSet(context, ctrl, p),
    );
  }

  _onQRViewCreated(QRViewController controller) {
    setState(() {
      this.controller = controller;
    });
    if (Platform.isAndroid) {
      controller.pauseCamera();
    }
    controller.resumeCamera();
    controller.scannedDataStream.listen((scanData) {
      setState(() {
        result = scanData;
        var code = result == null ? "" : result!.code.toString();
        if(result!.format == BarcodeFormat.qrcode) {
          controller.pauseCamera();
          //print("QR CODE FOUND");
          /*ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(content: Text('QR CODE FOUND - ${code.toString()}')),
          );*/

          VisitAppContext visitAppContext = widget.appContext!.getContext();
          if(!visitAppContext.sectionIds!.contains(code)) {
            ScaffoldMessenger.of(context).showSnackBar(
              SnackBar(content: Text(TranslationHelper.getFromLocale('invalidQRCode', widget.appContext!.getContext())), backgroundColor: kBlue2),
            );
            Navigator.of(context).pop();

          } else {
            Navigator.pushReplacement(
              context,
              MaterialPageRoute(
                builder: (context) {
                  return ArticlePage(visitAppContextIn: visitAppContext, articleId: code);
                },
              ),
            );
          }
        }
      });
    });
  }

  void _onPermissionSet(BuildContext context, QRViewController ctrl, bool p) {
    //log('${DateTime.now().toIso8601String()}_onPermissionSet $p');
    if (!p) {
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(content: Text('no Permission')),
      );
    }
  }

  @override
  void dispose() {
    controller?.dispose();
    super.dispose();
  }
}

showScannerDialog (BuildContext context, AppContext appContext) {
  showDialog(
      builder: (BuildContext context) => AlertDialog(
        shape: const RoundedRectangleBorder(
            borderRadius: BorderRadius.all(Radius.circular(10.0))
        ),
        content: ScannerDialog(appContext: appContext),
        contentPadding: EdgeInsets.zero,
      ), context: context
  );
}