sized_box_shrink_expand

Use 'SizedBox.{0}' to avoid needing to specify the 'height' and 'width'.

The analyzer produces this diagnostic when a SizedBox constructor invocation specifies the values of both height and width as either 0.0 or double.infinity.

The following code produces this diagnostic because both the height and width are 0.0:

import 'package:flutter/material.dart';

Widget build() {
  return SizedBox(
    height: 0.0,
    width: 0.0,
    child: const Text(''),
  );
}

The following code produces this diagnostic because both the height and width are double.infinity:

import 'package:flutter/material.dart';

Widget build() {
  return SizedBox(
    height: double.infinity,
    width: double.infinity,
    child: const Text(''),
  );
}

If both are 0.0, then use SizedBox.shrink:

import 'package:flutter/material.dart';

Widget build() {
  return SizedBox.shrink(
    child: const Text(''),
  );
}

If both are double.infinity, then use SizedBox.expand:

import 'package:flutter/material.dart';

Widget build() {
  return SizedBox.expand(
    child: const Text(''),
  );
}

Unless stated otherwise, the documentation on this site reflects Dart 3.8.1. Page last updated on 2025-05-08. View source or report an issue.