Flutter二维码扫描插件flutter_qr_scan的使用

QR码（扫描码/图片）识别，基于hetian9288/flutter_qr_reader的分叉版本。

我们添加了从QR码读取字节/原始数据的功能，因此onScan()回调函数现在有两个参数：

Future onScan(String data, String rawData) async {
  print(data);
  print(rawData);
}

详细文档可以参见hetian9288/flutter_qr_reader。

完整示例代码

import 'dart:io';

import 'package:flutter/material.dart';

import 'package:flutter_qr_scan/flutter_qr_scan.dart';
import 'package:flutter_qr_scan_example/scanViewDemo.dart';
import 'package:image_picker/image_picker.dart';
import 'package:permission_handler/permission_handler.dart';

void main() => runApp(MyApp());

class MyApp extends StatefulWidget {
  [@override](/user/override)
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  [@override](/user/override)
  void initState() {
    super.initState();
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(home: HomePage());
  }
}

class HomePage extends StatefulWidget {
  HomePage({Key key}) : super(key: key);

  [@override](/user/override)
  _HomePageState createState() => new _HomePageState();
}

class _HomePageState extends State<HomePage> {
  QrReaderViewController _controller;
  bool isOk = false;
  String data;
  String rawData;

  [@override](/user/override)
  void initState() {
    super.initState();
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('插件示例应用'),
      ),
      body: SingleChildScrollView(
        child: Column(
          children: <Widget>[
            FlatButton(
              onPressed: () async {
                final status = await Permission.camera.request();
                print(status);
                if (status.isGranted) {
                  showDialog(
                    context: context,
                    builder: (context) {
                      return Dialog(
                        child: Text("ok"),
                      );
                    },
                  );
                  setState(() {
                    isOk = true;
                  });
                }
              },
              child: Text("请求权限"),
              color: Colors.blue,
            ),
            FlatButton(
              onPressed: () async {
                Navigator.push(context,
                    MaterialPageRoute(builder: (context) => ScanViewDemo()));
              },
              child: Text("独立UI"),
            ),
            FlatButton(
                onPressed: () async {
                  var image = await ImagePicker().getImage(source: ImageSource.gallery);
                  if (image == null) return;
                  final rest = await FlutterQrReader.imgScan(File(image.path));
                  setState(() {
                    data = rest;
                  });
                },
                child: Text("识别图片")),
            FlatButton(
                onPressed: () {
                  assert(_controller != null);
                  _controller.setFlashlight();
                },
                child: Text("切换闪光灯")),
            FlatButton(
                onPressed: () {
                  assert(_controller != null);
                  _controller.startCamera(onScan);
                },
                child: Text("开始扫码（暂停后）")),
            if (data != null) Text('$data\nrawData: $rawData'),
            if (isOk)
              Container(
                width: 320,
                height: 350,
                child: QrReaderView(
                  width: 320,
                  height: 350,
                  callback: (container) {
                    this._controller = container;
                    _controller.startCamera(onScan);
                  },
                ),
              )
          ],
        ),
      ),
    );
  }

  void onScan(String v, List<Offset> offsets, String raw) {
    print([v, offsets, raw]);
    setState(() {
      data = v;
      rawData = raw;
    });
    _controller.stopCamera();
  }

  [@override](/user/override)
  void dispose() {
    // TODO: 实现dispose方法
    super.dispose();
  }
}