Flutter条码扫描插件flutter_barcode_reader的使用

flutter_barcode_reader 是一个用于在Flutter应用中添加条码扫描功能的插件，支持Android和iOS平台。以下是如何使用该插件的详细步骤及示例代码。

安装与配置

Android

对于Android平台，无需进行额外配置。

iOS

iOS平台需要Swift支持，具体步骤如下：

1. 创建新项目或修改现有项目：

   • 如果是新建项目，请确保选择“Include Swift support for iOS code”。
   • 设置最低部署目标为12，并将Swift版本设置为5。
   • 在/ios目录下运行pod install。

2. 修改现有项目：

   • 如果现有iOS代码是Swift，只需设置最低部署目标为12，并将Swift版本设置为5，然后运行pod install。
   • 如果现有iOS代码是Objective-C，则需创建一个新的带有Swift支持的Flutter项目，复制新的/ios文件夹替换现有项目中的/ios文件夹，并进行上述设置。

3. 权限配置：

   • 在Xcode中打开Info.plist，添加相机使用描述：

     <key>NSCameraUsageDescription</key>
     <string>Camera permission is required for barcode scanning.</string>
     

4. 添加依赖：

   • 在pubspec.yaml中添加依赖：

     dependencies:
       flutter:
         sdk: flutter
       flutter_barcode_reader: ^1.0.1
     

使用方法

一次性扫描

import 'package:flutter/material.dart';
import 'package:flutter_barcode_reader/flutter_barcode_reader.dart';

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

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

class _MyAppState extends State<MyApp> {
  String _scanBarcode = 'Unknown';

  Future<void> scanBarcodeNormal() async {
    String barcodeScanRes;
    try {
      barcodeScanRes = await FlutterBarcodeReader.scanBarcode(
          '#ff6666', 'Cancel', true, ScanMode.BARCODE);
      print(barcodeScanRes);
    } on PlatformException {
      barcodeScanRes = 'Failed to get platform version.';
    }

    if (!mounted) return;

    setState(() {
      _scanBarcode = barcodeScanRes;
    });
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(
        home: Scaffold(
            appBar: AppBar(title: const Text('Barcode scan')),
            body: Builder(builder: (BuildContext context) {
              return Container(
                  alignment: Alignment.center,
                  child: Column(
                      mainAxisAlignment: MainAxisAlignment.center,
                      children: <Widget>[
                        ElevatedButton(
                            onPressed: () => scanBarcodeNormal(),
                            child: Text('Start barcode scan')),
                        Text('Scan result : $_scanBarcode\n',
                            style: TextStyle(fontSize: 20))
                      ]));
            })));
  }
}

连续扫描

Future<void> startBarcodeScanStream() async {
  FlutterBarcodeReader.getBarcodeStreamReceiver(
          '#ff6666', 'Cancel', true, ScanMode.BARCODE)!
      .listen((barcode) => print(barcode));
}

示例Demo

完整的示例代码如下：

import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter_barcode_reader/flutter_barcode_reader.dart';

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

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

class _MyAppState extends State<MyApp> {
  String _scanBarcode = 'Unknown';

  Future<void> startBarcodeScanStream() async {
    FlutterBarcodeReader.getBarcodeStreamReceiver(
            '#ff6666', 'Cancel', true, ScanMode.BARCODE)!
        .listen((barcode) => print(barcode));
  }

  Future<void> scanQR() async {
    String barcodeScanRes;
    try {
      barcodeScanRes = await FlutterBarcodeReader.scanBarcode(
          '#ff6666', 'Cancel', true, ScanMode.QR);
      print(barcodeScanRes);
    } on PlatformException {
      barcodeScanRes = 'Failed to get platform version.';
    }

    if (!mounted) return;

    setState(() {
      _scanBarcode = barcodeScanRes;
    });
  }

  Future<void> scanBarcodeNormal() async {
    String barcodeScanRes;
    try {
      barcodeScanRes = await FlutterBarcodeReader.scanBarcode(
          '#ff6666', 'Cancel', true, ScanMode.BARCODE);
      print(barcodeScanRes);
    } on PlatformException {
      barcodeScanRes = 'Failed to get platform version.';
    }

    if (!mounted) return;

    setState(() {
      _scanBarcode = barcodeScanRes;
    });
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(
        home: Scaffold(
            appBar: AppBar(title: const Text('Barcode scan')),
            body: Builder(builder: (BuildContext context) {
              return Container(
                  alignment: Alignment.center,
                  child: Column(
                      mainAxisAlignment: MainAxisAlignment.center,
                      children: <Widget>[
                        ElevatedButton(
                            onPressed: () => scanBarcodeNormal(),
                            child: Text('Start barcode scan')),
                        ElevatedButton(
                            onPressed: () => scanQR(),
                            child: Text('Start QR scan')),
                        ElevatedButton(
                            onPressed: () => startBarcodeScanStream(),
                            child: Text('Start barcode scan stream')),
                        Text('Scan result : $_scanBarcode\n',
                            style: TextStyle(fontSize: 20))
                      ]));
            })));
  }
}