Standalone version of the AutoSizer component from react-virtualized.

npm install --save react-virtualized-auto-sizer

Some components (like those found in react-window or react-window) require numeric width and height parameters. The AutoSizer component can be useful if you want to pass percentage based dimensions.

import AutoSizer from "react-virtualized-auto-sizer";

// UI
<AutoSizer>
  {({ height, width }) => {
    // Use these actual sizes to calculate your percentage based sizes
  }}
</AutoSizer>;

Flex containers don't prevent their children from growing and AutoSizer greedily grows to fill as much space as possible. Combining the two can be problematic. The simple way to fix this is to nest AutoSizer inside of a block element (like a <div>) rather than putting it as a direct child of the flex container, like so:

<div style={{ display: 'flex' }}>
  <!-- Other children... -->
  <div style={{ flex: '1 1 auto' }}>
    <AutoSizer>
      {({ height, width }) => (
        <Component
          width={width}
          height={height}
          {...props}
        />
      )}
    </AutoSizer>
  </div>
</div>

AutoSizer expands to fill its parent but it will not stretch the parent. This is done to prevent problems with flexbox layouts. If AutoSizer is reporting a height (or width) of 0- then it's likely that the parent element (or one of its parents) has a height of 0.

The solution to this problem is often to add height: 100% or flex: 1 to the parent. One easy way to test this is to add a style property (eg background-color: red;) to the parent to visually confirm that it is the expected size.

You can use AutoSizer to control only one dimension of its child component using the disableHeight or disableWidth attributes. For example, a fixed-height component that should grow to fill the available width can be created like so:

<AutoSizer disableHeight>
  {({width}) => <Component height={200} width={width} {...props} />}
</AutoSizer>

This package targets ECMAScript 2015 (ES6) and requires a build tool such as babel-loader that is capable of parsing the ES6 class syntax.

The specification of Content Security Policy describes as the following:

This document defines Content Security Policy, a mechanism web applications can use to mitigate a broad class of content injection vulnerabilities, such as cross-site scripting (XSS).

To apply Content Security Policy, pass a nonce to AutoSizer and add a matching nonce-source to the Content-Security-Policy field in HTTP header.