- function aboveViewport(container, element, treshold) {
- return $(container).offset().top >= $(element).offset().top + $(element).height() + treshold;
- }
-
- function belowViewport(container, element, treshold) {
- return $(container).offset().top + $(container).height() + treshold <= $(element).offset().top;
- }
-
- var TRESHOLD = 600;
- var lastScroll = -1000;
-
- function checkScroll() {
- if (Math.abs($('#images').scrollTop() - lastScroll) > 300) {
- var container = $('#images');
- lastScroll = container.scrollTop();
-
- $('#images .image-box').each(function() {
- if (aboveViewport(container, this, TRESHOLD)) {
- $(this).html('loading...');
- } else if (belowViewport(container, this, TRESHOLD)) {
- $(this).html('loading...');
- } else {
- $(this).html('<img src="' + $(this).attr('src') + '" width="460" height="460"/>');
- }
- })
- }
- setTimeout(checkScroll, 2000);
- }
-