# sized_box_for_whitespace

> Details about the sized_box_for_whitespace diagnostic produced by the Dart analyzer.



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_Use a 'SizedBox' to add whitespace to a layout._

## Description

The analyzer produces this diagnostic when a `Container` is created using
only the `height` and/or `width` arguments.

## Example

The following code produces this diagnostic because the `Container` has
only the `width` argument:

```dart
import 'package:flutter/material.dart';

Widget buildRow() {
  return Row(
    children: <Widget>[
      const Text('...'),
      [!Container!](
        width: 4,
        child: Text('...'),
      ),
      const Expanded(
        child: Text('...'),
      ),
    ],
  );
}
```

## Common fixes

Replace the `Container` with a `SizedBox` of the same dimensions:

```dart
import 'package:flutter/material.dart';

Widget buildRow() {
  return Row(
    children: <Widget>[
      Text('...'),
      SizedBox(
        width: 4,
        child: Text('...'),
      ),
      Expanded(
        child: Text('...'),
      ),
    ],
  );
}
```

