jquery焦点图,带左右切换

演示地址:http://www.corange.cn/demo/3854/index.html
截图如下

主要代码

<script type="text/javascript" src="../jquery.js"></script>
<style type="text/css">
/* focus btn is little button */
body{ padding:0; margin:0;}
img{ border:none}
#focus{width:980px;height:400px;overflow:hidden;position:relative;margin:0;padding:0;}
#focus ul{height:400px;position:absolute;margin:0;padding:0;}
#focus ul li{float:left;width:980px;height:400px;overflow:hidden;position:relative;background:#000;}
#focus ul li div{position:absolute;overflow:hidden;}
#focus .btnBg{position:absolute;width:980px;height:20px;left:0;bottom:0;background:#000;}
#focus .btn{position:absolute;width:980px;height:10px;padding:5px 10px;bottom:0; text-align:center}
#focus .btn span{display:inline-block;_display:inline;_zoom:1;width:25px;height:10px;_font-size:0;margin-left:5px;cursor:pointer;background:#fff;}
#focus .btn span.on{background:#fff;}
#focus .preNext{width:45px;height:100px;position:absolute;top:130px;background:url(images/sprite.png) no-repeat 0 0;cursor:pointer;}
#focus .pre{left:0;}
#focus .next{right:0;background-position:right top;}
</style>
<script type="text/javascript">
$(function() {
var sWidth = $("#focus").width(); //获取焦点图的宽度（显示面积）
var len = $("#focus ul li").length; //获取焦点图个数
var index = 0;
var picTimer;

//以下代码添加数字按钮和按钮后的半透明条，还有上一页、下一页两个按钮
var btn = "<div class='btnBg'></div><div class='btn'>";
for(var i=0; i < len; i++) {
btn += "<span></span>";
}
btn += "</div><div class='preNext pre'></div><div class='preNext next'></div>";
$("#focus").append(btn);
$("#focus .btnBg").css("opacity",0.3);

//为小按钮添加鼠标滑入事件，以显示相应的内容
$("#focus .btn span").css("opacity",0.4).mouseover(function() {
index = $("#focus .btn span").index(this);
showPics(index);
}).eq(0).trigger("mouseover");

//上一页、下一页按钮透明度处理
$("#focus .preNext").css("opacity",0.2).hover(function() {
$(this).stop(true,false).animate({"opacity":"0.5"},300);
},function() {
$(this).stop(true,false).animate({"opacity":"0.2"},300);
});

//上一页按钮
$("#focus .pre").click(function() {
index -= 1;
if(index == -1) {index = len - 1;}
showPics(index);
});

//下一页按钮
$("#focus .next").click(function() {
index += 1;
if(index == len) {index = 0;}
showPics(index);
});

//本例为左右滚动，即所有li元素都是在同一排向左浮动，所以这里需要计算出外围ul元素的宽度
$("#focus ul").css("width",sWidth * (len));

//鼠标滑上焦点图时停止自动播放，滑出时开始自动播放
$("#focus").hover(function() {
clearInterval(picTimer);
},function() {
picTimer = setInterval(function() {
showPics(index);
index++;
if(index == len) {index = 0;}
},4000); //此4000代表自动播放的间隔，单位：毫秒
}).trigger("mouseleave");

//显示图片函数，根据接收的index值显示相应的内容
function showPics(index) { //普通切换
var nowLeft = -index*sWidth; //根据index值计算ul元素的left值
$("#focus ul").stop(true,false).animate({"left":nowLeft},300); //通过animate()调整ul元素滚动到计算出的position
//$("#focus .btn span").removeClass("on").eq(index).addClass("on"); //为当前的按钮切换到选中的效果
$("#focus .btn span").stop(true,false).animate({"opacity":"0.4"},300).eq(index).stop(true,false).animate({"opacity":"1"},300); //为当前的按钮切换到选中的效果
}
});

</script>


<div id="focus">
<ul>

<li><a href="" target="_parent"><img src="../eng/pic/2012032631611313.jpg" alt="" /></a></li>

<li><a href="" target="_parent"><img src="../eng/pic/2012032631640485.jpg" alt="" /></a></li>

<li><a href="" target="_parent"><img src="../eng/pic/2012032631680391.jpg" alt="" /></a></li>

</ul>
</div><!--focus end--> 


原文地址:http://www.corange.cn/archives/2012/09/3854.html