a88e99c83a
* reactify release-notes pages * update GHAE/ES react release notes to not rely on javascripts/release-notes.js
26 lines
642 B
TypeScript
26 lines
642 B
TypeScript
import { useState, useEffect, MutableRefObject, RefObject } from 'react'
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export function useOnScreen<T extends Element>(
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ref: MutableRefObject<T | undefined> | RefObject<T>,
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rootMargin: string = '0px'
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): boolean {
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const [isIntersecting, setIntersecting] = useState(false)
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useEffect(() => {
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const observer = new IntersectionObserver(
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([entry]) => {
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setIntersecting(entry.isIntersecting)
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},
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{
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rootMargin,
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}
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)
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if (ref.current) {
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observer.observe(ref.current)
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}
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return () => {
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ref.current && observer.unobserve(ref.current)
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}
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}, [])
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return isIntersecting
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}
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