JCarouselLite滚动bug的修护

官方网站：

http://www.gmarwaha.com/jquery/jcarousellite/

插件描述：

JCarouselLite是一款jquery插件，可以控制文档元素滚动，丰富的参数设置可以控制滚动的更多细节，是一款不可多得的滚动插件。

但是在如果我一共有10张图片 显示4张滚动3张是会发现 JCarouselLite 有一个比较大的bug。

修改后的代码：

/**
* jCarouselLite - jQuery plugin to navigate images/any content in a carousel style widget.
* @requires jQuery v1.2 or above
*
* http://gmarwaha.com/jquery/jcarousellite/
*
* Copyright (c) 2007 Ganeshji Marwaha (gmarwaha.com)
* Dual licensed under the MIT and GPL licenses:
* http://www.opensource.org/licenses/mit-license.php
* http://www.gnu.org/licenses/gpl.html
*
* Version: 1.0.1
* Note: Requires jquery 1.2 or above from version 1.0.1
*/

/**
* Creates a carousel-style navigation widget for images/any-content from a simple HTML markup.
*
* The HTML markup that is used to build the carousel can be as simple as...
*
*  <div class="carousel">
*      <ul>
*          <li><img src="image/1.jpg" alt="1"></li>
*          <li><img src="image/2.jpg" alt="2"></li>
*          <li><img src="image/3.jpg" alt="3"></li>
*      </ul>
*  </div>
*
* As you can see, this snippet is nothing but a simple div containing an unordered list of images.
* You don't need any special "class" attribute, or a special "css" file for this plugin.
* I am using a class attribute just for the sake of explanation here.
*
* To navigate the elements of the carousel, you need some kind of navigation buttons.
* For example, you will need a "previous" button to go backward, and a "next" button to go forward.
* This need not be part of the carousel "div" itself. It can be any element in your page.
* Lets assume that the following elements in your document can be used as next, and prev buttons...
*
* <button class="prev"><<</button>
* <button class="next">>></button>
*
* Now, all you need to do is call the carousel component on the div element that represents it, and pass in the
* navigation buttons as options.
*
* $(".carousel").jCarouselLite({
*      btnNext: ".next",
*      btnPrev: ".prev"
* });
*
* That's it, you would have now converted your raw div, into a magnificient carousel.
*
* There are quite a few other options that you can use to customize it though.
* Each will be explained with an example below.
*
* @param an options object - You can specify all the options shown below as an options object param.
*
* @option btnPrev, btnNext : string - no defaults
* @example
* $(".carousel").jCarouselLite({
*      btnNext: ".next",
*      btnPrev: ".prev"
* });
* @desc Creates a basic carousel. Clicking "btnPrev" navigates backwards and "btnNext" navigates forward.
*
* @option btnGo - array - no defaults
* @example
* $(".carousel").jCarouselLite({
*      btnNext: ".next",
*      btnPrev: ".prev",
*      btnGo: [".0", ".1", ".2"]
* });
* @desc If you don't want next and previous buttons for navigation, instead you prefer custom navigation based on
* the item number within the carousel, you can use this option. Just supply an array of selectors for each element
* in the carousel. The index of the array represents the index of the element. What i mean is, if the
* first element in the array is ".0", it means that when the element represented by ".0" is clicked, the carousel
* will slide to the first element and so on and so forth. This feature is very powerful. For example, i made a tabbed
* interface out of it by making my navigation elements styled like tabs in css. As the carousel is capable of holding
* any content, not just images, you can have a very simple tabbed navigation in minutes without using any other plugin.
* The best part is that, the tab will "slide" based on the provided effect. :-)
*
* @option mouseWheel : boolean - default is false
* @example
* $(".carousel").jCarouselLite({
*      mouseWheel: true
* });
* @desc The carousel can also be navigated using the mouse wheel interface of a scroll mouse instead of using buttons.
* To get this feature working, you have to do 2 things. First, you have to include the mouse-wheel plugin from brandon.
* Second, you will have to set the option "mouseWheel" to true. That's it, now you will be able to navigate your carousel
* using the mouse wheel. Using buttons and mouseWheel or not mutually exclusive. You can still have buttons for navigation
* as well. They complement each other. To use both together, just supply the options required for both as shown below.
* @example
* $(".carousel").jCarouselLite({
*      btnNext: ".next",
*      btnPrev: ".prev",
*      mouseWheel: true
* });
*
* @option auto : number - default is null, meaning autoscroll is disabled by default
* @example
* $(".carousel").jCarouselLite({
*      auto: 800,
*      speed: 500
* });
* @desc You can make your carousel auto-navigate itself by specfying a millisecond value in this option.
* The value you specify is the amount of time between 2 slides. The default is null, and that disables auto scrolling.
* Specify this value and magically your carousel will start auto scrolling.
*
* @option speed : number - 200 is default
* @example
* $(".carousel").jCarouselLite({
*      btnNext: ".next",
*      btnPrev: ".prev",
*      speed: 800
* });
* @desc Specifying a speed will slow-down or speed-up the sliding speed of your carousel. Try it out with
* different speeds like 800, 600, 1500 etc. Providing 0, will remove the slide effect.
*
* @option easing : string - no easing effects by default.
* @example
* $(".carousel").jCarouselLite({
*      btnNext: ".next",
*      btnPrev: ".prev",
*      easing: "bounceout"
* });
* @desc You can specify any easing effect. Note: You need easing plugin for that. Once specified,
* the carousel will slide based on the provided easing effect.
*
* @option vertical : boolean - default is false
* @example
* $(".carousel").jCarouselLite({
*      btnNext: ".next",
*      btnPrev: ".prev",
*      vertical: true
* });
* @desc Determines the direction of the carousel. true, means the carousel will display vertically. The next and
* prev buttons will slide the items vertically as well. The default is false, which means that the carousel will
* display horizontally. The next and prev items will slide the items from left-right in this case.
*
* @option circular : boolean - default is true
* @example
* $(".carousel").jCarouselLite({
*      btnNext: ".next",
*      btnPrev: ".prev",
*      circular: false
* });
* @desc Setting it to true enables circular navigation. This means, if you click "next" after you reach the last
* element, you will automatically slide to the first element and vice versa. If you set circular to false, then
* if you click on the "next" button after you reach the last element, you will stay in the last element itself
* and similarly for "previous" button and first element.
*
* @option visible : number - default is 3
* @example
* $(".carousel").jCarouselLite({
*      btnNext: ".next",
*      btnPrev: ".prev",
*      visible: 4
* });
* @desc This specifies the number of items visible at all times within the carousel. The default is 3.
* You are even free to experiment with real numbers. Eg: "3.5" will have 3 items fully visible and the
* last item half visible. This gives you the effect of showing the user that there are more images to the right.
*
* @option start : number - default is 0
* @example
* $(".carousel").jCarouselLite({
*      btnNext: ".next",
*      btnPrev: ".prev",
*      start: 2
* });
* @desc You can specify from which item the carousel should start. Remember, the first item in the carousel
* has a start of 0, and so on.
*
* @option scrool : number - default is 1
* @example
* $(".carousel").jCarouselLite({
*      btnNext: ".next",
*      btnPrev: ".prev",
*      scroll: 2
* });
* @desc The number of items that should scroll/slide when you click the next/prev navigation buttons. By
* default, only one item is scrolled, but you may set it to any number. Eg: setting it to "2" will scroll
* 2 items when you click the next or previous buttons.
*
* @option beforeStart, afterEnd : function - callbacks
* @example
* $(".carousel").jCarouselLite({
*      btnNext: ".next",
*      btnPrev: ".prev",
*      beforeStart: function(a) {
*          alert("Before animation starts:" + a);
*      },
*      afterEnd: function(a) {
*          alert("After animation ends:" + a);
*      }
* });
* @desc If you wanted to do some logic in your page before the slide starts and after the slide ends, you can
* register these 2 callbacks. The functions will be passed an argument that represents an array of elements that
* are visible at the time of callback.
*
*
* @cat Plugins/Image Gallery
* @author Ganeshji Marwaha/ganeshread@gmail.com
o = $.extend({      
btnPrev: null,   //上一张按钮   
btnNext: null,   //下一张按钮   
btnGo: null,      //跳转到第几张   
mouseWheel: false,   //是否支持鼠标滚轮，需要jquery.mousewheel.js   
auto: null,   //是否自动滚动   
     
speed: 200,   //滚动时长   
easing: null,   //滚动优化，需要jquery.easing.1.1.js   
     
vertical: false,   //滚动方向，true垂直，false水平   
circular: true,   //是否重复播放，首位相接   
visible: 3,         //显示图片数量   
start: 0,           //从第几个开始滚动显示   
scroll: 1,          //每次滚动数量   
     
beforeStart: null,   //滚动前调用函数   
afterEnd: null        //滚动后调用函数 
*/

(function ($) {                                          // Compliant with jquery.noConflict()
    $.fn.jCarouselLite = function (o) {
        o = $.extend({
            btnPrev: null,
            btnNext: null,
            btnGo: null,
            mouseWheel: false,
            auto: null,

            speed: 200,
            easing: null,

            vertical: false,
            circular: true,
            visible: 1,
            start: 0,
            scroll: 5,

            beforeStart: null,
            afterEnd: null,
            overStop: true//鼠标经过切换对象时，是否停止切换，并于鼠标离开后重启自动切换，前提是已开启自动切换
        }, o || {});

        return this.each(function () {                           // Returns the element collection. Chainable.

            var running = false, animCss = o.vertical ? "top" : "left", sizeCss = o.vertical ? "height" : "width";
            var div = $(this), ul = $("ul", div), tLi = $("li", ul), tl = tLi.size(), v = o.visible;

            if (o.circular) {
                ul.prepend(tLi.slice(tl - v - 1 + 1).clone(true))
              .append(tLi.slice(0, v).clone(true));
                o.start += v;
            }

            var li = $("li", ul), itemLength = li.size(), curr = o.start;
            div.css("visibility", "visible");

            li.css({ overflow: "hidden", "float": o.vertical ? "none" : "left" });
            ul.css({ margin: "0", padding: "0", position: "relative", "list-style-type": "none", "z-index": "1" });
            div.css({ overflow: "hidden", position: "relative", "z-index": "2", left: "0px" });

            var liSize = o.vertical ? height(li) : width(li);   // Full li size(incl margin)-Used for animation
            var ulSize = liSize * itemLength;                   // size of full ul(total length, not just for the visible items)
            var divSize = liSize * v;                           // size of entire div(total length for just the visible items)

            li.css({ width: li.width(), height: li.height() });
            ul.css(sizeCss, ulSize + "px").css(animCss, -(curr * liSize));

            div.css(sizeCss, divSize + "px");                     // Width of the DIV. length of visible images

            if (o.btnPrev)
                $(o.btnPrev).click(function () {
                    return go(curr - o.scroll);
                });

            if (o.btnNext)
                $(o.btnNext).click(function () {
                    return go(curr + o.scroll);
                });

            if (o.btnGo)
                $.each(o.btnGo, function (i, val) {
                    $(val).click(function () {
                        return go(o.circular ? o.visible + i : i);
                    });
                });

            if (o.mouseWheel && div.mousewheel)
                div.mousewheel(function (e, d) {
                    return d > 0 ? go(curr - o.scroll) : go(curr + o.scroll);
                });

            if (o.auto) {
                var startRun = setInterval(function () { go(curr + o.scroll); }, o.auto + o.speed);
                if (o.overStop) {
                    $(this).hover(function () {
                        clearInterval(startRun); //重置自动切换函数
                    }, function () {
                        startRun = setInterval(function () { go(curr + o.scroll); }, o.auto + o.speed);
                    });
                }
            }

            function vis() {
                return li.slice(curr).slice(0, v);
            };

            function go(to) {
                if (!running) {

                    if (o.beforeStart)
                        o.beforeStart.call(this, vis());

                    if (o.circular) {            // If circular we are in first or last, then goto the other end
                        if (to <= o.start - v - 1) {           // If first, then goto last
                            //ul.css(animCss, -((itemLength - (v * 2)) * liSize) + "px");
                            //                            // If "scroll" > 1, then the "to" might not be equal to the condition; it can be lesser depending on the number of elements.
                            // curr = to == o.start - v - 1 ? itemLength - (v * 2) - 1 : itemLength - (v * 2) - o.scroll;
                            curr = itemLength - v -1+to ;
                            ul.css(animCss, -((curr) * liSize) + "px");
                            curr = curr - o.scroll;

                        } else if (to >= itemLength - v + 1) { // If last, then goto first

                            // ul.css(animCss, -((v) * liSize) + "px");
                            // If "scroll" > 1, then the "to" might not be equal to the condition; it can be greater depending on the number of elements.
                            // curr = to == itemLength - v + 1 ? v + 1 : v + o.scroll;
                            curr = v + to + 1 - itemLength;
                            ul.css(animCss, -((curr) * liSize) + "px");
                            curr = curr + o.scroll;

                        } else curr = to;
                    } else {                    // If non-circular and to points to first or last, we just return.
                        if (to < 0 || to > itemLength - v) return;
                        else curr = to;
                    }                           // If neither overrides it, the curr will still be "to" and we can proceed.

                    running = true;

                    ul.animate(
                    animCss == "left" ? { left: -(curr * liSize)} : { top: -(curr * liSize) }, o.speed, o.easing,
                    function () {
                        if (o.afterEnd)
                            o.afterEnd.call(this, vis());
                        running = false;
                    }
                );
                    // Disable buttons when the carousel reaches the last/first, and enable when not
                    if (!o.circular) {
                        $(o.btnPrev + "," + o.btnNext).removeClass("disabled");
                        $((curr - o.scroll < 0 && o.btnPrev)
                        ||
                       (curr + o.scroll > itemLength - v && o.btnNext)
                        ||
                       []
                     ).addClass("disabled");
                    }

                }
                return false;
            };
        });
    };

    function css(el, prop) {
        return parseInt($.css(el[0], prop)) || 0;
    };
    function width(el) {
        return el[0].offsetWidth + css(el, 'marginLeft') + css(el, 'marginRight');
    };
    function height(el) {
        return el[0].offsetHeight + css(el, 'marginTop') + css(el, 'marginBottom');
    };

})(jQuery);

欢迎大家纠正，谢谢

 同时个人把常用的一些jquery插件做了一个demo，里面有jquery.dropkick-1.0.0.js、slider.js、 fullcalendar-1.5.2、jquery.grumble.js、jcarousellite_1.0.1.js（已修改）、 jquery.jqzoom.js、jquery.thickbox.js、jquery.jqzoom.js、jquery.lazyload.js、 jquery.soChange.js、jquery.uploadify.min.js、jquery.validate.js、 jquery.form.js、jquery.weekcalendar.js、jquery.ztree.core、 jquery.ztree.exedit-3.0.js、datepicker.js、jquery.clearfield.js、 jquery.hashchange-1.0.0.js、jquery.hoverIntent.js、jquery.limit- 1.2.source、qrcode.min.js、spin.js、LAB.src.js，以上js相应的demo都比较简单 ，不过有些demo html是几个js整合在一起的。希望对大家有帮助。

欢迎大家下载http://download.csdn.net/detail/dz45693/4363960