flutter_qr_scanner_widget 0.0.1

A QR Scanner widget for Flutter

example/lib/main.dart

import 'package:flutter/material.dart';
import 'package:flutter_qr_scanner_widget/flutter_qr_scanner_widget.dart';
import 'package:permission_handler/permission_handler.dart';

void main() => runApp(const MaterialApp(home: FlutterQrScannerExample()));

class FlutterQrScannerExample extends StatefulWidget {
  const FlutterQrScannerExample({Key? key}) : super(key: key);

  @override
  State<FlutterQrScannerExample> createState() =>
      _FlutterQrScannerExampleState();
}

class _FlutterQrScannerExampleState extends State<FlutterQrScannerExample>
    with WidgetsBindingObserver {
  FlutterQrScannerController? _flutterQrScannerController;

  bool isCameraPermissionGranted = false;

  String scannedText = 'Some Scanned Text';

  bool isFlashOn = false;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addObserver(this);
    _checkCameraPermission();
  }

  @override
  void dispose() {
    WidgetsBinding.instance.removeObserver(this);
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    if (state == AppLifecycleState.resumed) {
      // Resume the scanner
      _flutterQrScannerController?.resumeCamera();
    } else if (state == AppLifecycleState.paused) {
      // Pause the scanner
      _flutterQrScannerController?.pauseCamera();
    }
  }

  void _checkCameraPermission() async {
    var status = await Permission.camera.status;
    if (!status.isGranted) {
      // We don't have permission yet.
      isCameraPermissionGranted = false;
    } else {
      // We have permission. Update the UI if necessary.
      setState(() {
        isCameraPermissionGranted = true;
      });
    }
  }

  void _requestPermission() async {
    final result = await Permission.camera.request();
    setState(() {
      isCameraPermissionGranted = result.isGranted;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Flutter Scan QR example')),
      body: SizedBox(
        width: double.infinity,
        height: double.infinity,
        child: isCameraPermissionGranted
            ? Stack(
                children: [
                  SizedBox.expand(
                    child: FlutterQrScanner(
                      onMapViewCreated: _onMapViewCreated,
                    ),
                  ),
                  Positioned.fill(
                    top: 40,
                    child: Align(
                      alignment: Alignment.topCenter,
                      child: Text(
                        scannedText,
                        style: const TextStyle(
                          color: Colors.white,
                          fontSize: 32,
                        ),
                      ),
                    ),
                  ),
                  Positioned.fill(
                    bottom: 40,
                    child: Align(
                      alignment: Alignment.bottomCenter,
                      child: Row(
                        mainAxisSize: MainAxisSize.max,
                        mainAxisAlignment: MainAxisAlignment.center,
                        children: [
                          // Toggle Flash Icon
                          InkWell(
                            onTap: () {
                              _flutterQrScannerController?.toggleFlash();
                              setState(() {
                                isFlashOn = !isFlashOn;
                              });
                            },
                            child: Container(
                              width: 60,
                              height: 60,
                              decoration: const BoxDecoration(
                                shape: BoxShape.circle,
                                color: Colors.white,
                              ),
                              child: Icon(
                                isFlashOn ? Icons.flash_on : Icons.flash_off,
                                size: 36,
                                color: Colors.black,
                              ),
                            ),
                          ),
                          const SizedBox(
                            width: 60,
                          ),
                          // Switch camera icon
                          InkWell(
                            onTap: () {
                              _flutterQrScannerController?.toggleCamera();
                            },
                            child: Container(
                              width: 60,
                              height: 60,
                              decoration: const BoxDecoration(
                                shape: BoxShape.circle,
                                color: Colors.white,
                              ),
                              child: const Icon(
                                Icons.cameraswitch,
                                size: 36,
                                color: Colors.black,
                              ),
                            ),
                          ),
                        ],
                      ),
                    ),
                  ),
                ],
              )
            : SizedBox.expand(
                child: Center(
                  child: Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    children: <Widget>[
                      const Text('Camera permission is required to proceed.'),
                      const SizedBox(height: 20),
                      ElevatedButton(
                        onPressed: _requestPermission,
                        child: const Text('Request Permission'),
                      ),
                    ],
                  ),
                ),
              ),
      ),
    );
  }

  // load default
  void _onMapViewCreated(FlutterQrScannerController controller) {
    _flutterQrScannerController = controller;
    _flutterQrScannerController!.setOnResultReceivedCallback((scannedValue) {
      setState(() {
        scannedText = scannedValue;
      });
    });
  }
}