jQuery实现的图片分组切换焦点图插件

这是一款基于jQuery的图片切换焦点图插件，这款jQuery焦点图插件的特点是图片可以分组切换，也就是说一次可以切换多张图片，相比其他焦点图插件，它能节省更多的空间，可以向用户展示更多的图片，非常实用。

实现的代码。

html代码：

 <div class="device">

        <h2>

            <a href="javascript:;" class="pre">上一组</a><a href="javascript:;" class="next">下一组</a></h2>

        <div class="scroll">

            <ul>

                <li><a href="#">

                    <img src="images/1.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/2.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/3.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/4.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/5.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/1.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/2.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/3.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/4.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/5.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/1.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/2.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/3.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/4.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/5.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/1.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/2.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/3.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/4.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

                <li><a href="#">

                    <img src="images/5.jpg" /></a><a href="#" class="link">HTML5资源教程</a></li>

            </ul>

        </div>

    </div>

js代码：

  $(function () {

            var $number = Math.ceil($('.scroll ul li').length / 4); //获取滚动几屏个数

            var margin = 10; //设置图片间距

            var $w = $('.scroll li').width() + margin; // 一屏图片的宽度

            var $width = $w * $number * 2; //设置ul宽度

            var pre = $('.device .pre');

            var next = $('.device .next');

            if ($number == 1) { pre.hide(); next.hide(); }

            $('.scroll ul').width($width);

            var num = 0;

            function autoscroll() {

                num++;

                if ($number == 1) { return false }

                if (num == $number) {

                    num = 0;

                }

                var distance = -2 * $w * num;

                $('.scroll ul').stop().animate({ left: distance });

            }

            var scrollChange = setInterval(autoscroll, 8000);

            //鼠标悬停，暂停滚动

            $(".scroll ul,.pre,.next").mouseover(function () {

                $('.scroll ul').stop()

                clearInterval(scrollChange);

            });

            // 鼠标移走，滚动继续

            $('.scroll ul,.pre,.next').mouseout(function () {

                scrollChange = setInterval(autoscroll, 8000);

            });

            //下一组

            next.click(function () {

                num++;

                if (num >= $number) { num = 0 }

                var leftdis = -2 * $w * num;

                $('.scroll ul').stop().animate({ left: leftdis });

            });

            //上一组

            pre.click(function () {

                num--;

                if (num < 0) { num = $number - 1 }

                var rightdis = -2 * $w * num;

                $('.scroll ul').stop().animate({ left: rightdis });

            });

        });