flutter 二维码

一、生成二维码

https://pub.flutter-io.cn/packages/qr_flutter

qr_flutter: ^3.1.0

QrImage(
  data: "1234567890",
  version: QrVersions.auto,
  size: 200.0,
),

 全

//生成二维码
import 'package:flutter/material.dart';
import 'package:qr_flutter/qr_flutter.dart';
class RQTest extends StatefulWidget {
  @override
  _RQTestState createState() => _RQTestState();
}

class _RQTestState extends State<RQTest> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(),
      body: Center(
        child: QrImage(
          data: "1234567890",
          version: QrVersions.auto,
          size: 200.0,
        ),
      ),
    );
  }
}

二、扫描二维码

https://pub.flutter-io.cn/packages/barcode_scan

barcode_scan: 3.0.1 #生成二维码

            () async {
              var result = await BarcodeScanner.scan();

              print(result.type); // 返回结果类型(barcode, cancelled, failed)
              print(result.rawContent); //扫描返回的内容
              print(result.format); // The barcode format (as enum)
              print(result.formatNote); // If a unknown format was scanned this field contains a note
            }();

全

//扫描二维码
import 'package:flutter/material.dart';
import 'package:barcode_scan/barcode_scan.dart';
class RQTest extends StatefulWidget {
  @override
  _RQTestState createState() => _RQTestState();
}

class _RQTestState extends State<RQTest> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(),
      body: Center(
        child: RaisedButton(
          child: Text("扫一扫"),
          onPressed: (){
            () async {
              var result = await BarcodeScanner.scan();

              print(result.type); // 返回结果类型(barcode, cancelled, failed)
              print(result.rawContent); //扫描返回的内容
              print(result.format); // The barcode format (as enum)
              print(result.formatNote); // If a unknown format was scanned this field contains a note
            }();
          },
        )
      ),
    );
  }
} 

1.Android端

AndroidManifest.xml添加

    <!--照相机-->
    <uses-permission android:name="android.permission.CAMERA" />

项目级别build.gradle添加 ---外层

buildscript {
    ext.kotlin_version = '1.3.61'
    // ...
    dependencies {
        // ...
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}

应用级别build.gradle添加 --内层

apply plugin: 'kotlin-android'
// ...
dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
    // ...
}

build.gradle 这两个文件如果生成时默认勾选的kotlin，貌似不用在单独添加

报错：Manifest merger failed : uses-sdk:minSdkVersion 16 cannot be smaller than version 18 declared in library

说明某个依赖包的manifests中的minSdkVersion版本比项目的minSdkVersion要高

解决

1.更改项目的uses-sdk:minSdkVersion
2.更改依赖包的uses-sdk:minSdkVersion
3.在项目的manifests标签下添加

 xmlns:tools="http://schemas.android.com/tools"
 tools:overrideLibrary="依赖包的包名"

<uses-sdk tools:overrideLibrary="xxx.xxx.aaa, xxx.xxx.bbb"/>

2.IOS端

Info.plist添加

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