问题描述
我是颤振的初学者 任何人都可以帮助.....!!!!!! 如何解决此问题?
这是错误。
ImplicitlyAnimatedWidgetState<ImplicitlyAnimatedWidget> createState(); // ignore: no_logic_in_create_state,https://github.com/dart-lang/linter/issues/2345
我对颤振完全陌生。我试图用 VSCODE 配置 Flutter。但不幸的是,当我尝试使用 flutter 提供的默认代码运行时,我的构建失败了。
这是与 createState() 相关的问题
这是 Main.dart 文件
import 'package:flutter/material.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
// This widget is the root of your application.
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',theme: ThemeData(
// This is the theme of your application.
//
// Try running your application with "flutter run". You'll see the
// application has a blue toolbar. Then,without quitting the app,try
// changing the primarySwatch below to Colors.green and then invoke
// "hot reload" (press "r" in the console where you ran "flutter run",// or simply save your changes to "hot reload" in a Flutter IDE).
// Notice that the counter didn't reset back to zero; the application
// is not restarted.
primarySwatch: Colors.blue,),home: MyHomePage(title: 'Flutter Demo Home Page'),);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key,this.title}) : super(key: key);
// This widget is the home page of your application. It is stateful,meaning
// that it has a State object (defined below) that contains fields that affect
// how it looks.
// This class is the configuration for the state. It holds the values (in this
// case the title) provided by the parent (in this case the App widget) and
// used by the build method of the State. Fields in a Widget subclass are
// always marked "final".c
final String title;
@override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
int _counter = 0;
void _incrementCounter() {
setState(() {
// This call to setState tells the Flutter framework that something has
// changed in this State,which causes it to rerun the build method below
// so that the display can reflect the updated values. If we changed
// _counter without calling setState(),then the build method would not be
// called again,and so nothing would appear to happen.
_counter++;
});
}
@override
Widget build(BuildContext context) {
// This method is rerun every time setState is called,for instance as done
// by the _incrementCounter method above.
//
// The Flutter framework has been optimized to make rerunning build methods
// fast,so that you can just rebuild anything that needs updating rather
// than having to individually change instances of widgets.
return Scaffold(
appBar: AppBar(
// Here we take the value from the MyHomePage object that was created by
// the App.build method,and use it to set our appbar title.
title: Text(widget.title),body: Center(
// Center is a layout widget. It takes a single child and positions it
// in the middle of the parent.
child: Column(
// Column is also a layout widget. It takes a list of children and
// arranges them vertically. By default,it sizes itself to fit its
// children horizontally,and tries to be as tall as its parent.
//
// Invoke "debug painting" (press "p" in the console,choose the
// "Toggle Debug Paint" action from the Flutter Inspector in Android
// Studio,or the "Toggle Debug Paint" command in Visual Studio Code)
// to see the wireframe for each widget.
//
// Column has various properties to control how it sizes itself and
// how it positions its children. Here we use mainAxisAlignment to
// center the children vertically; the main axis here is the vertical
// axis because Columns are vertical (the cross axis would be
// horizontal).
mainAxisAlignment: MainAxisAlignment.center,children: <Widget>[
Text(
'You have pushed the button this many times:',Text(
'$_counter',style: Theme.of(context).textTheme.headline4,],floatingActionButton: FloatingActionButton(
onPressed: _incrementCounter,tooltip: 'Increment',child: Icon(Icons.add),// This trailing comma makes auto-formatting nicer for build methods.
);
}
}
我的 pubspec.yaml 文件:-
name: radio_app
description: A new Flutter project.
# The following line prevents the package from being accidentally published to
# pub.dev using `pub publish`. This is preferred for private packages.
publish_to: 'none' # Remove this line if you wish to publish to pub.dev
# The following defines the version and build number for your application.
# A version number is three numbers separated by dots,like 1.2.43
# followed by an optional build number separated by a +.
# Both the version and the builder number may be overridden in flutter
# build by specifying --build-name and --build-number,respectively.
# In Android,build-name is used as versionName while build-number used as versionCode.
# Read more about Android versioning at https://developer.android.com/studio/publish/versioning
# In iOS,build-name is used as CFBundleShortVersionString while build-number used as CFBundleVersion.
# Read more about iOS versioning at
# https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
version: 1.0.0+1
environment:
sdk: ">=2.7.0 <3.0.0"
dependencies:
flutter:
sdk: flutter
# The following adds the Cupertino Icons font to your application.
# Use with the CupertinoIcons class for iOS style icons.
cupertino_icons: ^1.0.2
dev_dependencies:
flutter_test:
sdk: flutter
# For information on the generic Dart part of this file,see the
# following page: https://dart.dev/tools/pub/pubspec
# The following section is specific to Flutter.
flutter:
# The following line ensures that the Material Icons font is
# included with your application,so that you can use the icons in
# the material Icons class.
uses-material-design: true
# To add assets to your application,add an assets section,like this:
# assets:
# - images/a_dot_burr.jpeg
# - images/a_dot_ham.jpeg
# An image asset can refer to one or more resolution-specific "variants",see
# https://flutter.dev/assets-and-images/#resolution-aware.
# For details regarding adding assets from package dependencies,see
# https://flutter.dev/assets-and-images/#from-packages
# To add custom fonts to your application,add a fonts section here,# in this "flutter" section. Each entry in this list should have a
# "family" key with the font family name,and a "fonts" key with a
# list giving the asset and other descriptors for the font. For
# example:
# fonts:
# - family: Schyler
# fonts:
# - asset: fonts/Schyler-Regular.ttf
# - asset: fonts/Schyler-Italic.ttf
# style: italic
# - family: Trajan Pro
# fonts:
# - asset: fonts/TrajanPro.ttf
# - asset: fonts/TrajanPro_Bold.ttf
# weight: 700
#
# For details regarding fonts from package dependencies,# see https://flutter.dev/custom-fonts/#from-packages
我跑
flutter doctor command
我做到了
flutter clean
flutter pub get
flutter upgarde
什么都不适合我。
我需要帮助:/
解决方法
您的用户名中有一个空格。尝试将 Flutter 安装到没有空格的路径。
我在开始使用 Flutter 时遇到了类似的问题,可能对你来说也是一样的。