react-use-scrollspy

Installation

react-use-scrollyspy is a React Hook which requires React 16.8.0 or later.

// yarn
yarn add react-use-scrollspy
// or npm
npm i react-use-scrollspy --S

Usage

import useScrollSpy from 'react-use-scrollspy';
...
const activeSection = useScrollSpy({
  sectionElementRefs: [], // Array of References to DOM elements
});

| Parameter | Default | Type | Description | | :----------------- | :-----: | :-----: | ------------------------------------------------ | | defaultValue | 0 | int | Default value that is returned (optional) | | offsetPx | 0 | int | Set offset (optional) | | sectionElementRefs | [] | [Ref] | Array of Refs to observe (e.g. via React refs) |

with Refs

Use React refs for section elements like in the provided example.

import React, { useRef } from 'react';
import useScrollSpy from 'react-use-scrollspy';

const App = () => {

  const sectionRefs = [
    useRef(null),
    useRef(null),
    useRef(null),
  ];

  const activeSection = useScrollSpy({
    sectionElementRefs: sectionRefs,
    offsetPx: -80,
  });

  return (
    <nav className="App-navigation">
      <span className={activeSection === 0 ? "App-navigation-item App-navigation-item--active" : "App-navigation-item"}>Section 1</span>
      <span className={activeSection === 1 ? "App-navigation-item App-navigation-item--active" : "App-navigation-item"}>Section 2</span>
      <span className={activeSection === 2 ? "App-navigation-item App-navigation-item--active" : "App-navigation-item"}>Section 3</span>
    </nav>

    <section className="App-section" ref={sectionRefs[0]}>
      <h1>Section 1</h1>
    </section>
    <section className="App-section" ref={sectionRefs[1]}>
      <h1>Section 2</h1>
    </section>
    <section className="App-section" ref={sectionRefs[2]}>
      <h1>Section 3</h1>
    </section>
  )