Intersection Observer

intersection-observer.js

if (!this.props.observeOnScroll) {
  return false
}

this.observer = new IntersectionObserver(entries => {
  entries.forEach(entry => {
    const { isIntersecting, intersectionRatio } = entry

    if (isIntersecting === true || intersectionRatio > 0) {
      this.createImage()
      this.setState({ intersecting: true })
      this.observer.disconnect()
      this.observer = null
    }
  })
}, {})

this.observer.observe(this.element)