jquery.cycle2.loader.js

/*! loader plugin for Cycle2;  version: 20131121 */
(function($) {
"use strict";

$.extend($.fn.cycle.defaults, {
    loader: false
});

$(document).on( 'cycle-bootstrap', function( e, opts ) {
    var addFn;

    if ( !opts.loader )
        return;

    // override API.add for this slideshow
    addFn = opts.API.add;
    opts.API.add = add;

    function add( slides, prepend ) {
        var slideArr = [];
        if ( $.type( slides ) == 'string' )
            slides = $.trim( slides );
        else if ( $.type( slides) === 'array' ) {
            for (var i=0; i < slides.length; i++ )
                slides[i] = $(slides[i])[0];
        }

        slides = $( slides );
        var slideCount = slides.length;

        if ( ! slideCount )
            return;

        slides.hide().appendTo('body').each(function(i) { // appendTo fixes #56
            var count = 0;
            var slide = $(this);
            var images = slide.is('img') ? slide : slide.find('img');
            slide.data('index', i);
            // allow some images to be marked as unimportant (and filter out images w/o src value)
            images = images.filter(':not(.cycle-loader-ignore)').filter(':not([src=""])');
            if ( ! images.length ) {
                --slideCount;
                slideArr.push( slide );
                return;
            }

            count = images.length;
            images.each(function() {
                // add images that are already loaded
                if ( this.complete ) {
                    imageLoaded();
                }
                else {
                    $(this).load(function() {
                        imageLoaded();
                    }).on("error", function() {
                        if ( --count === 0 ) {
                            // ignore this slide
                            opts.API.log('slide skipped; img not loaded:', this.src);
                            if ( --slideCount === 0 && opts.loader == 'wait') {
                                addFn.apply( opts.API, [ slideArr, prepend ] );
                            }
                        }
                    });
                }
            });

            function imageLoaded() {
                if ( --count === 0 ) {
                    --slideCount;
                    addSlide( slide );
                }
            }
        });

        if ( slideCount )
            opts.container.addClass('cycle-loading');
        

        function addSlide( slide ) {
            var curr;
            if ( opts.loader == 'wait' ) {
                slideArr.push( slide );
                if ( slideCount === 0 ) {
                    // #59; sort slides into original markup order
                    slideArr.sort( sorter );
                    addFn.apply( opts.API, [ slideArr, prepend ] );
                    opts.container.removeClass('cycle-loading');
                }
            }
            else {
                curr = $(opts.slides[opts.currSlide]);
                addFn.apply( opts.API, [ slide, prepend ] );
                curr.show();
                opts.container.removeClass('cycle-loading');
            }
        }

        function sorter(a, b) {
            return a.data('index') - b.data('index');
        }
    }
});

})(jQuery);