jquery.png交叉淡入淡出脚本在IE7/IE8上失败

我试图让两个alpha-24透明的.png文件相互交叉淡入。我通过修改一个相当不错的小脚本(感谢jqueryfordesigners.com)开始了这次冒险:

// wrap as a jQuery plugin and pass jQuery in to our anoymous function
    (function ($) {
        $.fn.cross = function (options) {
            return this.each(function (i) { 
                // cache the copy of jQuery(this) - the start image
                var $$ = $(this);

                // get the target from the backgroundImage + regexp
                var target = $$.css('backgroundImage').replace(/^url|[\(\)'"]/g, '');

                // nice long chain: wrap img element in span
                $$.wrap('<span style="position: relative;"></span>')
                    // change selector to parent - i.e. newly created span
                    .parent()
                    // prepend a new image inside the span
                    .prepend('<img>')
                    // change the selector to the newly created image
                    .find(':first-child')
                    // set the image to the target
                    .attr('src', target);

                // the CSS styling of the start image needs to be handled
                // differently for different browsers
                if ($.browser.mozilla) {
                    $$.css({
                        'position' : 'absolute', 
                        'left' : 0,
                        'background' : '',
                        'top' : this.offsetTop
                    });
                 } else if ($.browser.msie && $.browser.version == 8.0) {
                 $$.css({ 
                  'position' : 'absolute',
                  'left' : 0,
                  'background' : '',
                  '-ms-background-position-x' : '0px',
            '-ms-background-position-y' : '0px'
                 });

                } else if ($.browser.msie) {
                    $$.css({
                        'position' : 'absolute', 
                        'left' : 0,
                        'background' : '',
                        'top' : 0
                    }); 

                } else if ($.browser.opera && $.browser.version < 9.5) {
                    // Browser sniffing is bad - however opera < 9.5 has a render bug 
                    // so this is required to get around it we can't apply the 'top' : 0 
                    // separately because Mozilla strips the style set originally somehow...                    
                    $$.css({
                        'position' : 'absolute', 
                        'left' : 0,
                        'background' : '',
                        'top' : "0"
                    });
                } else { // Safari & Chrome
                    $$.css({
                        'position' : 'absolute', 
                        'left' : 0,
                        'background' : ''
                    });
                }

                // similar effect as single image technique, except using .animate 
                // which will handle the fading up from the right opacity for us
                $$.hover(function () {
                    $$.stop().animate({
                        opacity: 0
                    }, 250);
                }, function () {
                    $$.stop().animate({
                        opacity: 1
                    }, 250);
                });
            });
        };

    })(jQuery);

    // note that this uses the .bind('load') on the window object, rather than $(document).ready() 
    // because .ready() fires before the images have loaded, but we need to fire *after* because
    // our code relies on the dimensions of the images already in place.
    $(window).bind('load', function () {
        $('img.fade').cross();
    });

我做的主要修改是通过修复一些绝对定位错误,使它在IE7/8和WebKit中工作。现在唯一的问题是我遇到了这里讨论的一个问题-[stackoverflow.com/questions/1156985,ie7和ie8]一次只能处理一个图像的透明度。交叉淡入淡出使我在效果期间和之后得到一个灰色图像的结果。实际检查: http://dap-llc.com/work/

有没有人有一个好办法来解决这个问题?并且没有必要建议我淡化一个容器元素——必须有一种方法在IE的图像级别上做到这一点。