avoid_unnecessary_containers

Unnecessary instance of 'Container'.

The analyzer produces this diagnostic when a widget tree contains an instance of Container and the only argument to the constructor is child:.

The following code produces this diagnostic because the invocation of the Container constructor only has a child: argument:

import 'package:flutter/material.dart';

Widget buildRow() {
  return Container(
    child: Row(
      children: [
        Text('a'),
        Text('b'),
      ],
    )
  );
}

If you intended to provide other arguments to the constructor, then add them:

import 'package:flutter/material.dart';

Widget buildRow() {
  return Container(
    color: Colors.red.shade100,
    child: Row(
      children: [
        Text('a'),
        Text('b'),
      ],
    )
  );
}

If no other arguments are needed, then unwrap the child widget:

import 'package:flutter/material.dart';

Widget buildRow() {
  return Row(
    children: [
      Text('a'),
      Text('b'),
    ],
  );
}

Unless stated otherwise, the documentation on this site reflects Dart 3.7.3. Page last updated on 2025-05-08. View source or report an issue.