javascript 43 lines · 8 steps

Building an accessible star rating in React

A controlled star-rating widget that previews on hover while keeping the committed value and screen-reader semantics distinct.

Explained by highlit
React Intermediate controlled-component accessibility state-management event-handling conditional-rendering
1import { useState } from 'react';
2 
3function StarRating({ value = 0, max = 5, onChange, size = 24 }) {
4 const [hovered, setHovered] = useState(null);
5 const active = hovered ?? value;
6 
7 return (
8 <div role="radiogroup" aria-label="Rating" style={{ display: 'inline-flex', gap: 4 }}>
9 {Array.from({ length: max }, (_, i) => {
10 const rating = i + 1;
11 const filled = rating <= active;
12 return (
13 <button
14 key={rating}
15 type="button"
16 role="radio"
17 aria-checked={rating === value}
18 aria-label={`${rating} star${rating > 1 ? 's' : ''}`}
19 onClick={() => onChange?.(rating === value ? 0 : rating)}
20 onMouseEnter={() => setHovered(rating)}
21 onMouseLeave={() => setHovered(null)}
22 onFocus={() => setHovered(rating)}
23 onBlur={() => setHovered(null)}
24 style={{
25 background: 'none',
26 border: 'none',
27 padding: 0,
28 cursor: 'pointer',
29 fontSize: size,
30 lineHeight: 1,
31 color: filled ? '#f5a623' : '#d0d0d0',
32 transition: 'color 120ms ease',
33 }}
34 >
35 {filled ? '\u2605' : '\u2606'}
36 </button>
37 );
38 })}
39 </div>
40 );
41}
42 
43export default StarRating;
01 / 01
STEP 01

Walkthrough

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Three takeaways
  1. 1Separating transient hover state from the committed value lets you preview without mutating the source of truth.
  2. 2ARIA roles like radiogroup and radio turn a row of buttons into a control assistive tech understands.
  3. 3The nullish coalescing operator cleanly falls back to a default only when hover is genuinely absent.

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