https://www.delilahs.com/wp-content/themes/newave-theme/js/jquery.waitforimages.js?ver=7.1.3

1;(function ($) {
2    // Namespace all events.
3    var eventNamespace = 'waitForImages';
4
5    // CSS properties which contain references to images.
6    $.waitForImages = {
7        hasImageProperties: ['backgroundImage', 'listStyleImage', 'borderImage', 'borderCornerImage', 'cursor']
8    };
9
10    // Custom selector to find `img` elements that have a valid `src` attribute and have not already loaded.
11    $.expr[':'].uncached = function (obj) {
12        // Ensure we are dealing with an `img` element with a valid `src` attribute.
13        if (!$(obj).is('img[src!=""]')) {
14            return false;
15        }
16
17        // Firefox's `complete` property will always be `true` even if the image has not been downloaded.
18        // Doing it this way works in Firefox.
19        var img = new Image();
20        img.src = obj.src;
21        return !img.complete;
22    };
23
24    $.fn.waitForImages = function (finishedCallback, eachCallback, waitForAll) {
25
26        var allImgsLength = 0;
27        var allImgsLoaded = 0;
28
29        // Handle options object.
30        if ($.isPlainObject(arguments[0])) {
31            waitForAll = arguments[0].waitForAll;
32            eachCallback = arguments[0].each;
33			// This must be last as arguments[0]
34			// is aliased with finishedCallback.
35            finishedCallback = arguments[0].finished;
36        }
37
38        // Handle missing callbacks.
39        finishedCallback = finishedCallback || $.noop;
40        eachCallback = eachCallback || $.noop;
41
42        // Convert waitForAll to Boolean
43        waitForAll = !! waitForAll;
44
45        // Ensure callbacks are functions.
46        if (!$.isFunction(finishedCallback) || !$.isFunction(eachCallback)) {
47            throw new TypeError('An invalid callback was supplied.');
48        }
49
50        return this.each(function () {
51            // Build a list of all imgs, dependent on what images will be considered.
52            var obj = $(this);
53            var allImgs = [];
54            // CSS properties which may contain an image.
55            var hasImgProperties = $.waitForImages.hasImageProperties || [];
56            // To match `url()` references.
57            // Spec: http://www.w3.org/TR/CSS2/syndata.html#value-def-uri
58            var matchUrl = /url\(\s*(['"]?)(.*?)\1\s*\)/g;
59
60            if (waitForAll) {
61
62                // Get all elements (including the original), as any one of them could have a background image.
63                obj.find('*').addBack().each(function () {
64                    var element = $(this);
65
66                    // If an `img` element, add it. But keep iterating in case it has a background image too.
67                    if (element.is('img:uncached')) {
68                        allImgs.push({
69                            src: element.attr('src'),
70                            element: element[0]
71                        });
72                    }
73
74                    $.each(hasImgProperties, function (i, property) {
75                        var propertyValue = element.css(property);
76                        var match;
77
78                        // If it doesn't contain this property, skip.
79                        if (!propertyValue) {
80                            return true;
81                        }
82
83                        // Get all url() of this element.
84                        while (match = matchUrl.exec(propertyValue)) {
85                            allImgs.push({
86                                src: match[2],
87                                element: element[0]
88                            });
89                        }
90                    });
91                });
92            } else {
93                // For images only, the task is simpler.
94                obj.find('img:uncached')
95                    .each(function () {
96                    allImgs.push({
97                        src: this.src,
98                        element: this
99                    });
100                });
101            }
102
103            allImgsLength = allImgs.length;
104            allImgsLoaded = 0;
105
106            // If no images found, don't bother.
107            if (allImgsLength === 0) {
108                finishedCallback.call(obj[0]);
109            }
110
111            $.each(allImgs, function (i, img) {
112
113                var image = new Image();
114
115                // Handle the image loading and error with the same callback.
116                $(image).on('load.' + eventNamespace + ' error.' + eventNamespace, function (event) {
117                    allImgsLoaded++;
118
119                    // If an error occurred with loading the image, set the third argument accordingly.
120                    eachCallback.call(img.element, allImgsLoaded, allImgsLength, event.type == 'load');
121
122                    if (allImgsLoaded == allImgsLength) {
123                        finishedCallback.call(obj[0]);
124                        return false;
125                    }
126
127                });
128
129                image.src = img.src;
130            });
131        });
132    };
133}(jQuery));