/react-use-scrollspy

Flexible React Hook to automatically update navigation based on scroll position

Primary LanguageTypeScriptMIT LicenseMIT

react-use-scrollspy

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Example

Installation

react-use-scrollspy 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)
scrollingElement window Ref Target of the scrolling (e.g. via React refs)) (optional)

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>
  )