Is There A Way To Access Whether A Portion Of A Webpage Is Being Rendered On Screen Or Not Via Javascript?

Currently our logic runs within an iframe on clients pages. We have the request to now detect whether that iFrame is currently in the viewing window or not (scrolled off-screen).

Solution 1:

You can calculate if the object is inside your viewport or not.

http://plnkr.co/edit/91gybbZ7sYVELEYvy1IK?p=preview

$(document).ready(function() {
  myElement = $('.someObject');
  window.onscroll = function() {

    var screenTop = $(window).scrollTop();
    var screenBottom = screenTop + $(window).height();    
    var elTop = $(myElement).offset().top;
    var elBottom = elTop + $(myElement).height();

    var info = 'screenTop:' + screenTop + ' screenBottom:' + screenBottom + ' elTop:' + elTop + ' elBottom:' + elBottom;

    if((elBottom <= screenBottom) && (elTop >= screenTop)) {
      $('.info').html('Element is in view + <small>' + info + '</small>');
    } else {
      $('.info').html('Element is out of view + <small>' + info + '</small>');
    }

  }
})