mobile-app/lib/presentation/screens/scan_barcode/sc_scan_barcode.dart

import 'dart:io' show Platform;

import 'package:barcode_scan/barcode_scan.dart';
import 'package:farm_tpf/presentation/custom_widgets/widget_toast.dart';
import 'package:farm_tpf/presentation/screens/home/home.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:fluttertoast/fluttertoast.dart';

class ScanBarcodeScreen extends StatefulWidget {
  @override
  _ScanBarcodeScreenState createState() => _ScanBarcodeScreenState();
}

class _ScanBarcodeScreenState extends State<ScanBarcodeScreen> {
  ScanResult scanResult;

  var _aspectTolerance = 0.00;
  var _selectedCamera = -1;
  var _useAutoFocus = true;
  var _autoEnableFlash = false;
  final GlobalKey<ScaffoldState> _scaffoldKey = new GlobalKey<ScaffoldState>();
  FlutterToast flutterToast;

  @override
  // ignore: type_annotate_public_apis
  initState() {
    super.initState();
    flutterToast = FlutterToast(context);
    scan();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      key: _scaffoldKey,
      appBar: AppBar(
        title: Text("Quét mã QR"),
      ),
      body: Center(
        child: scanResult == null ? Container() : Text(scanResult?.rawContent),
      ),
    );
  }

  Future scan() async {
    try {
      var options = ScanOptions(
        strings: {
          "cancel": "Huỷ",
          "flash_on": "Bật flash",
          "flash_off": "Tắt flash",
        },
        useCamera: _selectedCamera,
        autoEnableFlash: _autoEnableFlash,
        android: AndroidOptions(
          aspectTolerance: _aspectTolerance,
          useAutoFocus: _useAutoFocus,
        ),
      );
      var result = await BarcodeScanner.scan(options: options);
      setState(() {
        scanResult = result;
        if (1 != 1) {
          Navigator.of(context).pop();
          Navigator.of(context)
              .push(MaterialPageRoute(builder: (_) => HomePage()));
        } else {
          flutterToast.showToast(
              child:
                  WidgetToast(message: "Mã QR không đúng", color: Colors.red));
          Navigator.of(context).pop();
        }
      });
    } on PlatformException catch (e) {
      var result = ScanResult(
        type: ResultType.Error,
        format: BarcodeFormat.unknown,
      );

      if (e.code == BarcodeScanner.cameraAccessDenied) {
        setState(() {
          result.rawContent = 'Vui lòng cấp quyền truy cập camera';
        });
      } else {
        result.rawContent = 'Vui lòng cấp quyền truy cập camera.';
      }
      setState(() {
        scanResult = result;
      });
      flutterToast.showToast(
          child: WidgetToast(
              message: "Vui lòng cấp quyền truy cập camera.",
              color: Colors.red));
      Navigator.of(context).pop();
    }
  }
}