Card contructor : 1 required argument(s) expected, but 0 found

[ratsey]

Using the example card in the framework yields the above error.

new Card( // 1 required argument(s) expected, but 0 found.
   child: new Column( 
     mainAxisSize: MainAxisSize.min,
     children: <Widget>[
       const ListTile(
         leading: const Icon(Icons.album),
         title: const Text('The Enchanted Nightingale'),
         subtitle: const Text('Music by Julie Gable. Lyrics by Sidney Stein.'),
       ),
       new ButtonTheme.bar( // make buttons use the appropriate styles for cards
         child: new ButtonBar(
           children: <Widget>[
             new FlatButton(
               child: const Text('BUY TICKETS'),
               onPressed: () { /* ... */ },
             ),
             new FlatButton(
               child: const Text('LISTEN'),
               onPressed: () { /* ... */ },
             ),
           ],
         ),
       ),
     ],
   ),
 )

Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel beta, v0.6.0, on Microsoft Windows [Version 10.0.17134.228], locale en-US)
[√] Android toolchain - develop for Android devices (Android SDK 27.0.3)
[√] Android Studio (version 3.1)
[√] IntelliJ IDEA Community Edition (version 2018.1)
[√] VS Code, 64-bit edition (version 1.26.1)
[√] Connected devices (1 available)

[zoechi]

Is this at runtime or in the IDE.
Please add the exact and full error message.

[zoechi]

I can't reproduce.
Can you try reproducing in a new project and post the whole main.dart?

[ratsey]

Created a new Flutter project, vanilla, using VS Code. Even with no adjustments, an error on attempting to run.

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      title: 'Flutter Demo',
      theme: new 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 press Run > Flutter Hot Reload in IntelliJ). Notice that the
        // counter didn't reset back to zero; the application is not restarted.
        primarySwatch: Colors.blue,
      ),
      home: new 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() => new _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 new Scaffold(
      appBar: new 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: new Text(widget.title),
      ),
      body: new Center(
        // Center is a layout widget. It takes a single child and positions it
        // in the middle of the parent.
        child: new Column(
          // Column is also 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 paint" (press "p" in the console where you ran
          // "flutter run", or select "Toggle Debug Paint" from the Flutter tool
          // window in IntelliJ) 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>[
            new Text(
              'You have pushed the button this many times:',
            ),
            new Text(
              '$_counter',
              style: Theme.of(context).textTheme.display1,
            ),
          ],
        ),
      ),
      floatingActionButton: new FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: new Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}

Launching lib\main.dart on Android SDK built for x86 64 in debug mode...
compiler message: file:///E:/flutter/packages/flutter/lib/src/material/card.dart:69:10: Error: Duplicated parameter name 'child'.
compiler message:     this.child,
compiler message:          ^^^^^
compiler message: file:///E:/flutter/packages/flutter/lib/src/material/card.dart:63:21: Error: Other parameter named 'child'.
compiler message:   const Card(Column child, {
compiler message:                     ^^^^^
compiler message: file:///E:/flutter/packages/flutter/lib/src/material/paginated_data_table.dart:382:16: Error: Too few positional arguments: 1 required, 0 given.
compiler message:     return new Card(
compiler message:                ^
compiler message: file:///E:/flutter/packages/flutter/lib/src/material/card.dart:63:9: Error: Found this candidate, but the arguments don't match.
compiler message:   const Card(Column child, {
compiler message:         ^
Compiler failed on E:\Users\jens\Projects\CardBug\card_bug\lib\main.dart
FAILURE: Build failed with an exception.
* Where:
Script 'E:\flutter\packages\flutter_tools\gradle\flutter.gradle' line: 450
* What went wrong:
Execution failed for task ':app:flutterBuildDebug'.
> Process 'command 'E:\flutter\bin\flutter.bat'' finished with non-zero exit value 1
* 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 8s
Gradle build failed: 1
Exited (sigterm)

From framework card.dart:

class Card extends StatelessWidget {
  /// Creates a material design card.
  const Card(Column child, {
    Key key,
    this.color,
    this.elevation,
    this.shape,
    this.margin = const EdgeInsets.all(4.0),
    this.child,    **<< Doesn't like this**
    this.semanticContainer = true,
  }) : super(key: key);

[√] Flutter (Channel beta, v0.6.0, on Microsoft Windows [Version 10.0.17134.228], locale en-US)
    • Flutter version 0.6.0 at E:\flutter
    • Framework revision 9299c02cf7 (2 weeks ago), 2018-08-16 00:35:12 +0200
    • Engine revision e3687f70c7
    • Dart version 2.1.0-dev.0.0.flutter-be6309690f

[√] Android toolchain - develop for Android devices (Android SDK 27.0.3)
    • Android SDK at C:\Users\jens\AppData\Local\Android\sdk
    • Android NDK location not configured (optional; useful for native profiling support)
    • Platform android-27, build-tools 27.0.3
    • Java binary at: E:\Program Files\Android\Android Studio\jre\bin\java
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1024-b02)
    • All Android licenses accepted.

[√] Android Studio (version 3.1)
    • Android Studio at E:\Program Files\Android\Android Studio
    • Flutter plugin version 27.1.1
    • Dart plugin version 173.4700
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1024-b02)

[√] IntelliJ IDEA Community Edition (version 2018.1)
    • IntelliJ at E:\Program Files\JetBrains\IntelliJ IDEA Community Edition 181.4203.6
    • Flutter plugin version 22.2.3
    • Dart plugin version 181.4096.12

[√] VS Code, 64-bit edition (version 1.26.1)
    • VS Code at C:\Program Files\Microsoft VS Code
    • Flutter extension version 2.18.0

[√] Connected devices (1 available)
    • Android SDK built for x86 64 • emulator-5554 • android-x64 • Android 9 (API 28) (emulator)

• No issues found

[zoechi]

Please try executing flutter clean in a terminal window in the project directory and then try again.
From the error output above it looks more like your Flutter installation is corrupted.
I'd try to delete the folder that contains it and re-install.

[ratsey]

flutter clean did nothing so I deleted the Flutter folder and reinstalled. The sample app now works, but my app seems to have gone from bad to worse:

FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':app:preDebugBuild'.
> Android dependency 'com.android.support:support-v4' has different version for the compile (27.0.1) and runtime (27.1.1) classpath. You should manually set the same version via DependencyResolution
* 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 1s
Gradle build failed: 1
Exited (sigterm)

Looks to be related to ##14020

Had to add this to build.gradle and now works:

        resolutionStrategy.eachDependency { details ->
            if (details.requested.group == 'com.android.support'
                    && !details.requested.name.contains('multidex') ) {
                details.useVersion "27.0.1"
            }
        }

[zoechi]

Thanks for the update!

The issue seems to be solved. I don't think there is something left to do for the Flutter team.

The "has different version for ..." error is a different one. If you think there is something to do, please create a new issue.

Add a comment if you disagree to reopen.

[JCzz]

I get the same error in VS Code:

From sample code: https://docs.flutter.io/flutter/material/Card-class.html

Error: Too few positional arguments: 1 required, 0 given.
      child: Card(
                 ^

[zoechi]

@JCzz perhaps https://github.com/flutter/flutter/wiki/Workarounds-for-common-issues#corrupted-cache

[JCzz]

Thanks @zoechi

Did not work though:

1. Recreated the project(plugin) - copying lib and native ios imp. classes : flutter create --template=plugin -i swift <NAME>
2. pub cache repair
3. Delete ~/.pub-cache/hosted and/or ~/.pub-cache/git

[zoechi]

Please try also https://github.com/flutter/flutter/wiki/Workarounds-for-common-issues#flutter-installation-corrupted

[JCzz]

Super thanks Günter ( @zoechi )

This worked! I must say, you know you way around :-)

Thanks