-/*
- * Lazy Load - jQuery plugin for lazy loading images
- *
- * Copyright (c) 2007-2009 Mika Tuupola
- *
- * Licensed under the MIT license:
- * http://www.opensource.org/licenses/mit-license.php
- *
- * Project home:
- * http://www.appelsiini.net/projects/lazyload
- *
- * Version: 1.3.2
- *
- */
(function($) {
-
- $.fn.lazyload = function(options) {
+ jQuery.fn.lazyload = function(pattern, options) {
var settings = {
- threshold : 0,
- failurelimit : 0,
- event : "scroll",
- effect : "show",
- container : window
+ threshold: 0,
+ scrollThreshold: 300,
+ placeholder: 'loading...',
+ checkInterval: 2000
};
-
- if(options) {
+
+ if (options) {
$.extend(settings, options);
}
-
- /* Fire one scroll event per scroll. Not one scroll event per image. */
- var elements = this;
- if ("scroll" == settings.event) {
- $(settings.container).bind("scroll", function(event) {
- var counter = 0;
- elements.each(function() {
- if (!$.belowthefold(this, settings) &&
- !$.rightoffold(this, settings)) {
- $(this).trigger("appear");
- } else {
- if (counter++ > settings.failurelimit) {
- return false;
- }
- }
- });
- /* Remove image from array so it is not looped next time. */
- var temp = $.grep(elements, function(element) {
- return !element.loaded;
- });
- elements = $(temp);
- });
+
+ var container = this;
+ container.data('lazyload:lastCheckedScrollTop', -10000);
+
+ function aboveViewport(container, element, threshold) {
+ return $(container).offset().top >= $(element).offset().top + $(element).height() + threshold;
}
- return this.each(function() {
- var self = this;
- /* TODO: use .data() instead of .attr() */
- $(self).attr("original", $(self).attr("src"));
- if ("scroll" != settings.event
- || $.belowthefold(self, settings)
- || $.rightoffold(self, settings)) {
- if (settings.placeholder) {
- $(self).attr("src", settings.placeholder);
- } else {
- $(self).removeAttr("src");
- }
- self.loaded = false;
- } else {
- self.loaded = true;
- }
-
- /* When appear is triggered load original image. */
- $(self).one("appear", function() {
- if (!this.loaded) {
- $("<img />")
- .bind("load", function() {
- $(self)
- .hide()
- .attr("src", $(self).attr("original"))
- [settings.effect](settings.effectspeed);
- self.loaded = true;
- })
- .attr("src", $(self).attr("original"));
- };
- });
-
- /* When wanted event is triggered load original image */
- /* by triggering appear. */
- if ("scroll" != settings.event) {
- $(self).bind(settings.event, function(event) {
- if (!self.loaded) {
- $(self).trigger("appear");
+ function belowViewport(container, element, threshold) {
+ return $(container).offset().top + $(container).height() + threshold <= $(element).offset().top;
+ }
+
+ function checkScroll() {
+ if (Math.abs(container.scrollTop() - container.data('lazyload:lastCheckedScrollTop')) > settings.scrollThreshold) {
+ container.data('lazyload:lastCheckedScrollTop', container.scrollTop());
+
+ $(pattern, container).each(function() {
+ if (aboveViewport(container, this, settings.threshold)
+ || belowViewport(container, this, settings.threshold)) {
+ $(this).html(settings.placeholder);
+ } else {
+ $(this).html('');
+ var self = this;
+ $('<img src="' + $(this).attr('src') + '" width="' + $(this).width() + '" />').load(function() {
+ if ($(this).height() > $(self).height()) {
+ $(self).height($(this).height());
+ }
+ }).appendTo(this);
}
- });
+ })
}
- });
-
- };
-
- /* Convenience methods in jQuery namespace. */
- /* Use as $.belowthefold(element, {threshold : 100, container : window}) */
-
- $.belowthefold = function(element, settings) {
- if (settings.container === undefined || settings.container === window) {
- var fold = $(window).height() + $(window).scrollTop();
- }
- else {
- var fold = $(settings.container).offset().top + $(settings.container).height();
- }
- return fold <= $(element).offset().top - settings.threshold;
- };
-
- $.rightoffold = function(element, settings) {
- if (settings.container === undefined || settings.container === window) {
- var fold = $(window).width() + $(window).scrollLeft();
+ setTimeout(checkScroll, settings.checkInterval);
}
- else {
- var fold = $(settings.container).offset().left + $(settings.container).width();
- }
- return fold <= $(element).offset().left - settings.threshold;
- };
-
- $.aboveViewport = function(element, settings) {
- if (settings.container === undefined || settings.container === window) {
- var top = $(window).scrollTop();
- }
- else {
- var top = $(settings.container).offset().top;
- }
- return top >= $(element).offset().bottom - settings.threshold;
+
+ checkScroll();
};
-
- /* Custom selectors for your convenience. */
- /* Use as $("img:below-the-fold").something() */
-
- $.extend($.expr[':'], {
- "below-the-fold" : "$.belowthefold(a, {threshold : 0, container: window})",
- "above-the-fold" : "!$.belowthefold(a, {threshold : 0, container: window})",
- "right-of-fold" : "$.rightoffold(a, {threshold : 0, container: window})",
- "left-of-fold" : "!$.rightoffold(a, {threshold : 0, container: window})"
- });
-
})(jQuery);
fnp / redakcja.git / blobdiff