本文介绍了参数不匹配的闭包调用:function' _myListView.functionOne'的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
我不知道为什么此错误会出现在控制台框中.一切看起来都很好,但下面仍然出现
I don't know why this error is appearing in the console box. everything appears fine but still this below appears
这是我用于列表查看的代码
import 'package:flutter/material.dart';
import 'package:linear_gradient/linear_gradient.dart';
import 'package:gradient_text/gradient_text.dart';
import 'package:apple_beauty/cdetails.dart';
Gradient gradient = LinearGradient(
colors: [Colors.teal, Colors.deepOrange, Colors.pink]);
class RamList extends StatefulWidget {
@override
_RamListState createState() => _RamListState();
}
class _RamListState extends State<RamList> {
@override
Widget build(BuildContext context) {
return _myListView(context);
}
}
Widget _myListView(BuildContext context) {
final titles = [
'1st',
'2nd',
'3rd',
'4th',
'5th',
];
final numbers = [
'1 ',
'2 ',
'3 ',
'4 ',
'5 ',
];
functionOne() {
Navigator.push(
context, new MaterialPageRoute(builder: (context) => RamOne()));
}
functionTwo() {
Navigator.push(context, MaterialPageRoute(builder: (context) => RamTwo()));
}
functionThree() {
Navigator.push(
context, MaterialPageRoute(builder: (context) => RamThree()));
}
functionFour() {
Navigator.push(context, MaterialPageRoute(builder: (context) => RamFour()));
}
functionFive(BuildContext context)=>_onAlertButtonPressed1(context);
final List<Function> onTaps = [
functionOne,
functionTwo,
functionThree,
functionFour,
functionFive,
];
return ListView.builder(
itemCount: titles.length,
itemBuilder: (context, index) {
return Card(
elevation: 50,
child: InkWell(
splashColor: Colors.green,
highlightColor: Colors.red,
child: Row(
children: <Widget>[
Container(
height: 100.0,
width:50.0,
decoration: BoxDecoration(
gradient:LinearGradientStyle.linearGradient(
orientation:LinearGradientStyle.ORIENTATION_HORIZONTAL,
gradientType: LinearGradientStyle.GRADIENT_TYPE_AMIN
)
),),
Container(
margin: EdgeInsets.all(10),
child: Text(
numbers[index],
)),
Flexible(child: Container(
margin: EdgeInsets.all(10),
child: GradientText((titles[index]),
gradient:gradient,
style:TextStyle(fontSize:20.0,fontWeight:FontWeight.bold, ),
),
//Text(titles[index]),
))
],
),
onTap: () => onTaps[index](context),
));
});
}
_onAlertButtonPressed1(context) {
AlertDialog alert = AlertDialog(
title: Text('Coming soon'),
content: Text("This link will be available in future updates"),
actions: [
],
);
showDialog(
context: context,
builder: (BuildContext context) {
return alert;
},
);
}
这是我用于LISTVIEW导航详细信息的代码
import 'package:flutter/material.dart';
import 'package:flutter_html/flutter_html.dart';
//import 'package:html/dom.dart' as dom;
import 'package:gradient_app_bar/gradient_app_bar.dart';
class RamOne extends StatefulWidget {
RamOne({Key key, this.title}) : super(key: key);
final String title;
@override
_RamOneState createState() => new _RamOneState();
}
class _RamOneState extends State<RamOne> {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: GradientAppBar(
gradient: LinearGradient(
colors: [Colors.green, Colors.greenAccent]),
title: Text('Overview'),
),
body: new Center(
child: SingleChildScrollView(
child: Html(
data: """ <h1>1st page</h1>
""",
),
),
));
}}
class RamTwo extends StatefulWidget {
RamTwo({Key key, this.title}) : super(key: key);
final String title;
@override
_RamTwoState createState() => new _RamTwoState();
}
class _RamTwoState extends State<RamTwo> {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: GradientAppBar(
gradient: LinearGradient(
colors: [Colors.green, Colors.greenAccent]),
title: Text('Nutritional Value'),
),
body: new Center(
child: SingleChildScrollView(
child: Html(
data: """
<h1>1st page</h1>""",
),
),
));
}}
class RamThree extends StatefulWidget {
RamThree({Key key, this.title}) : super(key: key);
final String title;
@override
_RamThreeState createState() => new _RamThreeState();
}
class _RamThreeState extends State<RamThree> {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: GradientAppBar(
gradient: LinearGradient(
colors: [Colors.green, Colors.greenAccent]),
title: Text('Types of apple'),
),
body: new Center(
child: SingleChildScrollView(
child: Html(
data: """
<h1>1st page</h1>
""",
),
),
));
}}
class RamFour extends StatefulWidget {
RamFour({Key key, this.title}) : super(key: key);
final String title;
@override
_RamFourState createState() => new _RamFourState();
}
class _RamFourState extends State<RamFour> {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: GradientAppBar(
gradient: LinearGradient(
colors: [Colors.green, Colors.greenAccent]),
title: Text('Good for Neuron'),
),
body: new Center(
child: SingleChildScrollView(
child: Html(
data: """
<h1>1st page</h1>
""",
),
),
));
}}
}}
推荐答案
您忘记将参数 BuildContext上下文
添加到函数中
代码段
You forgot to add parameter BuildContext context
to your function
code snippet
functionOne(BuildContext context) {
Navigator.push(
context, new MaterialPageRoute(builder: (context) => RamOne()));
}
工作演示
完整代码
import 'package:flutter/material.dart';
import 'package:linear_gradient/linear_gradient.dart';
import 'package:gradient_text/gradient_text.dart';
//import 'package:apple_beauty/cdetails.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".
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>[
Expanded(flex:5, child: RamList()),
Text(
'You have pushed the button this many times:',
),
Text(
'$_counter',
style: Theme.of(context).textTheme.display1,
),
],
),
),
floatingActionButton: FloatingActionButton(
onPressed: _incrementCounter,
tooltip: 'Increment',
child: Icon(Icons.add),
), // This trailing comma makes auto-formatting nicer for build methods.
);
}
}
Gradient gradient =
LinearGradient(colors: [Colors.teal, Colors.deepOrange, Colors.pink]);
class RamList extends StatefulWidget {
@override
_RamListState createState() => _RamListState();
}
class _RamListState extends State<RamList> {
@override
Widget build(BuildContext context) {
return _myListView(context);
}
}
Widget _myListView(BuildContext context) {
final titles = [
'1st',
'2nd',
'3rd',
'4th',
'5th',
];
final numbers = [
'1 ',
'2 ',
'3 ',
'4 ',
'5 ',
];
functionOne(BuildContext context) {
Navigator.push(
context, new MaterialPageRoute(builder: (context) => RamOne()));
}
functionTwo(BuildContext context) {
Navigator.push(context, MaterialPageRoute(builder: (context) => RamTwo()));
}
functionThree(BuildContext context) {
Navigator.push(
context, MaterialPageRoute(builder: (context) => RamThree()));
}
functionFour(BuildContext context) {
Navigator.push(context, MaterialPageRoute(builder: (context) => RamFour()));
}
functionFive(BuildContext context) => _onAlertButtonPressed1(context);
final List<Function> onTaps = [
functionOne,
functionTwo,
functionThree,
functionFour,
functionFive,
];
return ListView.builder(
itemCount: titles.length,
itemBuilder: (context, index) {
return Card(
elevation: 50,
child: InkWell(
splashColor: Colors.green,
highlightColor: Colors.red,
child: Row(
children: <Widget>[
Container(
height: 100.0,
width: 50.0,
decoration: BoxDecoration(
gradient: LinearGradientStyle.linearGradient(
orientation:
LinearGradientStyle.ORIENTATION_HORIZONTAL,
gradientType:
LinearGradientStyle.GRADIENT_TYPE_AMIN)),
),
Container(
margin: EdgeInsets.all(10),
child: Text(
numbers[index],
)),
Flexible(
child: Container(
margin: EdgeInsets.all(10),
child: GradientText(
(titles[index]),
gradient: gradient,
style: TextStyle(
fontSize: 20.0,
fontWeight: FontWeight.bold,
),
),
//Text(titles[index]),
))
],
),
onTap: () => onTaps[index](context),
));
});
}
_onAlertButtonPressed1(context) {
AlertDialog alert = AlertDialog(
title: Text('Coming soon'),
content: Text("This link will be available in future updates"),
actions: [],
);
showDialog(
context: context,
builder: (BuildContext context) {
return alert;
},
);
}
class RamOne extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Text("RamOne");
}
}
class RamTwo extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Text("RamTwo");
}
}
class RamThree extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Text("RamThree");
}
}
class RamFour extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Text("RamFour");
}
}
这篇关于参数不匹配的闭包调用:function&#39; _myListView.functionOne&#39;的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!