The named parameter 'child' isn't defined. in Center() constructor

Question

I ran flutter upgrade today, and now I am getting an error that says- [dart] The named parameter \'child\' isn\'t defined. The project is newly created and the default code

Answer 1

It happens because of the old cache. Just clean the cache with the following command

flutter clean cache

Answer 2

I just had the same issue. It looks like I changed a flutter lib file by mistake.

To fix this, without reinstalling Flutter SDK:

• go to your Flutter SDK installation path
• open terminal and type: git status
• it will show the modified files in red (ex: modified: packages/flutter/lib/src/widgets/basic.dart
• revert modifications file using: git checkout FILE_PATH (ex: git checkout packages/flutter/lib/src/widgets/basic.dart)

Answer 3

Clean the project cache by running

flutter clean cache

Then invalidate caches / restart Android Studio or VS Code.

Answer 4

1. Go to file Settings
2. Search Flutter (in the search bar)
3. Provide Flutter SDK path

Answer 5

Try Restarting your Analysis Dart Server.

1. At the the bottom of Android Studio click on the 'Dart Analysis' tab
2. Click on the Restart icon.

Answer 6

In my case it happens when I name the widget with the same name of a flutter component, like so:

class OutlineButton extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return OutlineButton(
      child: Text('+R\$ 5'),
      onPressed: () {},
      borderSide: BorderSide(color: Colors.grey),
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(30.0),
      ),
    );
  }
}

You need to change the name of the created component with a different name, for example:

class CustomOutlineButton extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return OutlineButton(
      child: Text('+R\$ 5'),
      onPressed: () {},
      borderSide: BorderSide(color: Colors.grey),
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(30.0),
      ),
    );
  }
}