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[redakcja.git] / project / static / js / jquery.lazyload.js

diff --git a/project/static/js/jquery.lazyload.js b/project/static/js/jquery.lazyload.js
index 98a74c1..ea3de6f 100644 (file)
--- a/project/static/js/jquery.lazyload.js
+++ b/project/static/js/jquery.lazyload.js
@@ -1,141 +1,49 @@
-/*
- * 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('lastScroll', -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('lastScroll')) > settings.scrollThreshold) {
+                container.data('lastScroll', 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);