README.md

react-use-scrollspy

⚠️ Heads up: React Hooks are not part of a stable React release yet. ⚠️

Installation

React-use-scrollyspy is a React Hook which requires React 16.7.0-alpha 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({
  sectionElements: [], // Array of DOM elements
});

Parameter	Default	Type	Description
defaultValue	0	int	Default value that is returned (optional)
offsetPx	0	int	Set offset (optional)
sectionElements	[]	[(DOM) Element]	Array of DOM elements 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({
    sectionElements: sectionRefs.map(ref => ref.current),
    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>
  )

with Document.querySelectorAll()

...Todo