探索Flutter Barcode Scanner：一款高效的二维码/条形码扫描库

import 'package:flutter/material.dart';
import 'package:barcode_scan/barcode_scan.dart';
 
class BarcodeScannerPage extends StatefulWidget {
  @override
  _BarcodeScannerPageState createState() => _BarcodeScannerPageState();
}
 
class _BarcodeScannerPageState extends State<BarcodeScannerPage> {
  String _scanResult = 'Unknown';
  String _scanResultType = 'Unknown type';
  int _scanResultFormat = 0;
 
  // 扫描二维码/条形码
  Future scanBarcode() async {
    try {
      // 调用扫描功能并获取结果
      final ScanResult result = await BarcodeScanner.scan();
      setState(() {
        _scanResult = result.type + ': ' + result.rawContent;
        _scanResultType = result.type;
        _scanResultFormat = result.format;
      });
    } on PlatformException catch (e) {
      if (e.code == BarcodeScanner.CameraAccessDenied) {
        setState(() {
          _scanResult = 'Camera permission was denied';
        });
      } else {
        setState(() {
          _scanResult = 'Unknown error: $e';
        });
      }
    } on FormatException {
      setState(() {
        _scanResult = 'No barcode was scanned';
      });
    }
  }
 
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Barcode Scanner'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text('Scan result: $_scanResult'),
            SizedBox(height: 20),
            Text('Scan result type: $_scanResultType'),
            SizedBox(height: 20),
            Text('Scan result format: $_scanResultFormat'),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: scanBarcode,
        tooltip: 'Scan',
        child: Icon(Icons.camera_alt),
      ),
    );
  }
}

这段代码展示了如何在Flutter应用中使用barcode_scan插件来实现二维码/条形码扫描功能。它首先导入了必要的包，定义了一个BarcodeScannerPage的StatefulWidget，并在其状态中维护扫描结果。scanBarcode方法异步调用扫描功能，并处理可能发生的异常，如相机访问被拒绝或扫描结果格式错误。最后，build方法构建了包含扫描结果展示和扫描按钮的用户界面。