Scroll infinito

infinite-scroll.js

window.onscroll = function onScroll() {
  var htmlEl = document.documentElement,
    alturaJanela = htmlEl.clientHeight,
    alturaTotal = Math.max(document.body.scrollHeight, htmlEl.scrollHeight, document.body.offsetHeight, htmlEl.offsetHeight, htmlEl.clientHeight);

  // Aplique a lógica que quiser, usei: se o scroll 
  if(alturaTotal - 2 * alturaJanela < window.scrollY) {
    carregarDados();
  }
  window.onscroll = null;
  setTimeout(function () {
    window.onscroll = onScroll;
  }, 250)
}