huixiang_app/lib/qr/qr_code_scan.dart

import 'package:flutter/material.dart';
import 'package:flutter_qr_reader/flutter_qr_reader.dart';
import 'package:flutter_smart_dialog/flutter_smart_dialog.dart';
import 'package:huixiang/generated/l10n.dart';
import 'package:huixiang/view_widget/my_appbar.dart';
import 'package:flutter_screenutil/flutter_screenutil.dart';
import 'package:huixiang/view_widget/tips_dialog.dart';
import 'package:image_picker_gallery_camera/image_picker_gallery_camera.dart';
import 'package:permission_handler/permission_handler.dart';

class QrCodeScanPage extends StatefulWidget {
  @override
  State<StatefulWidget> createState() {
    return _QrCodeScanPage();
  }
}

class _QrCodeScanPage extends State<QrCodeScanPage> {
  GlobalKey<_QrCodeScanPage> qrViewKey = GlobalKey();

  QrReaderViewController viewController;

  @override
  void initState() {
    super.initState();

    readerHeight = MediaQuery.of(context).size.height;
    Future.delayed(Duration(seconds: 1), () {
      buildReaderView();
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Container(
        child: Stack(
          children: [
            Positioned(
              child: qrReaderView != null
                  ? Column(
                children: [
                  Expanded(child: qrReaderView, flex: readerHeight.toInt(),),
                  // Expanded(child: qrReaderView, flex: readerHeight,),

                ],
              )
                  : Container(
                      width: MediaQuery.of(context).size.width,
                      height: MediaQuery.of(context).size.height,
                    ),
              top: 0,
              bottom: 0,
              left: 0,
              right: 0,
            ),
            Positioned(
              child: MyAppBar(
                title: "扫码",
                titleColor: Colors.white,
                leadingColor: Colors.white,
                brightness: Brightness.dark,
                background: Colors.transparent,
                action: Container(
                  alignment: Alignment.center,
                  margin: EdgeInsets.only(right: 16.w),
                  child: GestureDetector(
                    onTap: () {
                      openStorage();
                    },
                    child: Text(
                      S.of(context).xiangce,
                      style: TextStyle(
                        color: Colors.white,
                        fontSize: 18.sp,
                        fontWeight: FontWeight.bold,
                      ),
                    ),
                  ),
                ),
              ),
              top: 0,
              left: 0,
              right: 0,
            ),
          ],
        ),
      ),
    );
  }

  QrReaderView qrReaderView;
  double readerHeight ;

  buildReaderView() async {
    double screenWidth = MediaQuery.of(context).size.width;

    readerHeight = 1920.0 / 1080.0 * screenWidth;
    print("object: $readerHeight");
    qrReaderView = await QrReaderView(
      key: qrViewKey,
      callback: onScan,
      width: MediaQuery.of(context).size.width,
      height: readerHeight,
    );
    setState(() {});
  }

  ///打开相册
  openStorage() async {
    if (await Permission.storage.isGranted) {
      var image = await ImagePickerGC.pickImage(
          context: context, source: ImgSource.Gallery);
      String filePath = image.path;
      final String data = await FlutterQrReader.imgScan(filePath);
      showData(data);
    } else {
      await Permission.storage.request();
      openStorage();
    }
  }

  startCameraResult(String data, List<Offset> offset) async {
    showData(data);
    this.viewController.stopCamera();
  }

  Future onScan(QrReaderViewController viewController) async {
    this.viewController = viewController;
    await this.viewController.startCamera(startCameraResult);
  }

  showData(String data) {
    SmartDialog.show(
        widget: Tips(
          () {},
          text: "$data",
        ),
        onDismiss: () {
          Future.delayed(Duration(seconds: 1), () {
            this.viewController.startCamera(startCameraResult);
          });
        });
  }

  @override
  void dispose() {
    if (this.viewController != null) {
      this.viewController.stopCamera();
    }
    super.dispose();
  }
}