I am updating an old project. This qr code scanner is giving an error.The project had previously run on flutter 2.10. There are errors in Flutter 3.0.
import 'package:flutter/material.dart';
import 'package:qr_code_scanner/qr_code_scanner.dart';
import 'dart:io';
import 'package:flutter/foundation.dart';
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
// This widget is the root of your application.
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: const MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
const MyHomePage({Key? key, required this.title}) : super(key: key);
final String title;
@override
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
final GlobalKey qrKey = GlobalKey(debugLabel: 'QR');
Barcode? result;
QRViewController? controller;
// In order to get hot reload to work we need to pause the camera if the platform
// is android, or resume the camera if the platform is iOS.
@override
void reassemble() {
super.reassemble();
if (Platform.isAndroid) {
controller!.pauseCamera();
} else if (Platform.isIOS) {
controller!.resumeCamera();
}
}
@override
Widget build(BuildContext context) {
return Scaffold(
body: Column(
children: <Widget>[
Expanded(
flex: 5,
child: QRView(
key: qrKey,
onQRViewCreated: _onQRViewCreated,
),
),
Expanded(
flex: 1,
child: Center(
child: (result != null)
? Text(
'Barcode Type: ${describeEnum(result!.format)} Data: ${result!.code}')
: Text('Scan a code'),
),
)
],
),
);
}
void _onQRViewCreated(QRViewController controller) {
this.controller = controller;
controller.scannedDataStream.listen((scanData) {
setState(() {
result = scanData;
});
});
}
@override
void dispose() {
controller?.dispose();
super.dispose();
}
}
Error
Warning: unexpected element (uri:"", local:"base-extension"). Expected elements are <{}codename>,<{}layoutlib>,<{}api-level>
/C:/src/flutter/.pub-cache/hosted/pub.dartlang.org/qr_code_scanner-0.7.0/lib/src/qr_code_scanner.dart:68:20: Warning: Operand of null-aware operation '!' has type 'WidgetsBinding' which excludes null.
- 'WidgetsBinding' is from 'package:flutter/src/widgets/binding.dart' ('/C:/src/flutter/packages/flutter/lib/src/widgets/binding.dart').
WidgetsBinding.instance!.addObserver(_observer);
^
/C:/src/flutter/.pub-cache/hosted/pub.dartlang.org/qr_code_scanner-0.7.0/lib/src/qr_code_scanner.dart:86:20: Warning: Operand of null-aware operation '!' has type 'WidgetsBinding' which excludes null.
- 'WidgetsBinding' is from 'package:flutter/src/widgets/binding.dart' ('/C:/src/flutter/packages/flutter/lib/src/widgets/binding.dart').
WidgetsBinding.instance!.removeObserver(_observer);
^
e: C:\src\flutter\.pub-cache\hosted\pub.dartlang.org\qr_code_scanner-0.7.0\android\src\main\kotlin\net\touchcapture\qr\flutterqr\QRView.kt: (23, 1): Class 'QRView' is not abstract and does not implement abstract member public abstract fun onRequestPermissionsResult(p0: Int, p1: Array<(out) String!>, p2: IntArray): Boolean defined in io.flutter.plugin.common.PluginRegistry.RequestPermissionsResultListener
e: C:\src\flutter\.pub-cache\hosted\pub.dartlang.org\qr_code_scanner-0.7.0\android\src\main\kotlin\net\touchcapture\qr\flutterqr\QRView.kt: (216, 26): Null can not be a value of a non-null type String
e: C:\src\flutter\.pub-cache\hosted\pub.dartlang.org\qr_code_scanner-0.7.0\android\src\main\kotlin\net\touchcapture\qr\flutterqr\QRView.kt: (247, 26): Null can not be a value of a non-null type String
e: C:\src\flutter\.pub-cache\hosted\pub.dartlang.org\qr_code_scanner-0.7.0\android\src\main\kotlin\net\touchcapture\qr\flutterqr\QRView.kt: (310, 5): 'onRequestPermissionsResult' overrides nothing
e: C:\src\flutter\.pub-cache\hosted\pub.dartlang.org\qr_code_scanner-0.7.0\android\src\main\kotlin\net\touchcapture\qr\flutterqr\QRViewFactory.kt: (10, 1): Class 'QRViewFactory' is not abstract and does not implement abstract base class member public abstract fun create(p0: Context?, p1: Int, p2: Any?): PlatformView defined in io.flutter.plugin.platform.PlatformViewFactory
e: C:\src\flutter\.pub-cache\hosted\pub.dartlang.org\qr_code_scanner-0.7.0\android\src\main\kotlin\net\touchcapture\qr\flutterqr\QRViewFactory.kt: (13, 5): 'create' overrides nothing
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':qr_code_scanner:compileDebugKotlin'.
> Compilation error. See log for more details
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
* Get more help at https://help.gradle.org
BUILD FAILED in 21s
Running Gradle task 'assembleDebug'... 22.5s
Exception: Gradle task assembleDebug failed with exit code 1
flutter doctor -v
[√] Flutter (Channel stable, 3.0.0, on Microsoft Windows [Version 10.0.19043.1645], locale en-US)
• Flutter version 3.0.0 at C:\src\flutter
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision ee4e09cce0 (2 days ago), 2022-05-09 16:45:18 -0700
• Engine revision d1b9a6938a
• Dart version 2.17.0
• DevTools version 2.12.2
Checking Android licenses is taking an unexpectedly long time...[√] Android toolchain - develop for Android devices (Android SDK version 32.1.0-rc1)
• Android SDK at C:\Users\User\AppData\Local\Android\sdk
• Platform android-32, build-tools 32.1.0-rc1
• Java binary at: C:\Program Files\Android\Android Studio\jre\bin\java
• Java version OpenJDK Runtime Environment (build 11.0.11 9-b60-7590822)
• All Android licenses accepted.
[√] Chrome - develop for the web
• Chrome at C:\Program Files (x86)\Google\Chrome\Application\chrome.exe
[√] Visual Studio - develop for Windows (Visual Studio Professional 2022 17.1.3)
• Visual Studio at C:\Program Files\Microsoft Visual Studio\2022\Professional
• Visual Studio Professional 2022 version 17.1.32328.378
• Windows 10 SDK version 10.0.19041.0
[√] Android Studio (version 2021.1)
• Android Studio at C:\Program Files\Android\Android Studio
• Flutter plugin can be installed from:
https://plugins.jetbrains.com/plugin/9212-flutter
• Dart plugin can be installed from:
https://plugins.jetbrains.com/plugin/6351-dart
• Java version OpenJDK Runtime Environment (build 11.0.11 9-b60-7590822)
[√] VS Code (version 1.67.1)
• VS Code at C:\Users\User\AppData\Local\Programs\Microsoft VS Code
• Flutter extension version 3.40.0
[√] Connected device (5 available)
• SM T500 (mobile) • R9AR702P83X • android-arm64 • Android 11 (API 30)
• sdk gphone x86 (mobile) • emulator-5554 • android-x86 • Android 11 (API 30) (emulator)
• Windows (desktop) • windows • windows-x64 • Microsoft Windows [Version 10.0.19043.1645]
• Chrome (web) • chrome • web-javascript • Google Chrome 101.0.4951.54
• Edge (web) • edge • web-javascript • Microsoft Edge 101.0.1210.39
[√] HTTP Host Availability
• All required HTTP hosts are available
• No issues found!
What should I do to make it work? Before everything was fine, I updated my project to the latest version of flutter and now I get this error.
CodePudding user response：
Downgrade the flutter to the previous version "flutter downgrade" until an upgrade to flutter 3.0.0 provided by owners of all packages you are used in your project .
CodePudding user response：
You can directly import the library in this way:
qr_code_scanner:
git:
url: https://github.com/xeinebiu/qr_code_scanner.git
ref: fix_break_changes_platform