jquery——左右按钮点击切换一组图片功能

12/6/2015来源:Javascript教程人气:901

一、最终效果

二、功能分析

1、需求分析

点击左边PRe按钮,显示前面三个图片,点击右边的next按钮,显示后面的一组(三个)图片。初始化只显示next按钮,到最后一组只显示pre按钮,中间过程两按钮都显示。

2、html结构分析

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 <div class="activity" id="activity-slide">
        <a href="javascript:void(0)" class="pg_left ps_pre"></a>
        <a href="Javascript:void(0)" class="pg_right ps_next" ></a>
          <ul class="clearfix">
            <li><a href="javascript:;"><img src="images/activity01-1410.jpg"></a></li>
            <li><a href="javascript:;"><img src="images/activity02-1410.jpg"></a></li>
            <li><a href="javascript:;"><img src="images/activity03-1410.jpg"></a></li>
            <li><a href="javascript:;"><img src="images/activity03-1410.jpg"></a></li>
            <li><a href="javascript:;"><img src="images/activity02-1410.jpg"></a></li>
      </ul>
</div>
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 #activity-slide是整个幻灯的入口,后面会将其作为参数来调用幻灯功能。

 两个按钮ps_pre和ps_next将添加click事件响应点击切换功能。

 3、功能分析

因为左右切换都是三个为一组的切换,如果li总个数不是3的倍数时,需要增加li节点填满。

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//需要追加的li节点个数
var addli = 0;
//一组切换3个li
var num=3;
var lisize = a.find("ul li").size();//获取li个数

//判断需要添加的li节点数量
var reminder=lisize%num;
if(lisize%num!=0){addli = num-reminder;}
else{addli = 0;}
addlist();
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上面是判断得到需要追加的个数lisize,然后调用addlist追加。

addlist如下,从ul的第一个li开始复制,需要几个就复制出几个节点追加。节点追加完毕后重新计算ul的宽度。

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        function addlist(){
            for(i=0;i<addli;i++){
                var html = a.find("ul li").eq(i).html();
                a.find("ul").append("<li>"+html+"</li>");    
            }
            a.find("ul").CSS({"width":(w_li+margin_li*2)*(lisize+addli)});
        }
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现在准备工作已经完成了。接下来就是给按钮添加响应事件。在幻灯切换时涉及到左右按钮的显示和隐藏,所以先说这个按钮显示功能,将此分装成一个函数btnshow。

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        /***
        参数说明:
        now:当前是第几组,默认是0
        c:总共有几组
        d:初始化时li的个数
        e:每组显示li个数
        ***/
        function btnshow(now,c,d,e){
            if(d<=e){//如果初始化时li的个数小于一组要显示的数,则不显示pre和next按钮
                a.find(".ps_next").hide();
                a.find(".ps_pre").hide();
            }else if(now==0){//初始化now=0,显示第一组,只显示next
                a.find(".ps_next").show();
                a.find(".ps_pre").hide();    
            }else if(now==c-1){//显示到最后一组,只显示pre
                a.find(".ps_next").hide();
                a.find(".ps_pre").show();    
            }else{//显示中间组,pre和next都需要显示
                a.find(".ps_next").show();
                a.find(".ps_pre").show();
            }
        }
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 接下来幻灯切换。这里a是传入的参数,也就是 #activity-slide。给它下面的所以的pre和next添加响应。

向前一组,组数now减一,now是几,就让ul的margin-left为负几倍的组宽(即3倍的(li宽度+margin宽度)),然后显示对于按钮即可。

向后滑动一组li同理。

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        function photoscroll(){
            a.find(".ps_pre").on("click",function(){//console.log(num);    
                now--;
                if(now >= 0){                  
                    a.find("ul").animate({"margin-left":-now*num*(w_li+margin_li*2)});
                    btnshow(now,parseInt((lisize+addli)/num),lisize,num);
                }
            });

            a.find(".ps_next").on("click",function(){//console.log(num);    
                now++;
                if(now < (lisize+addli)/num){    
                    a.find("ul").animate({"margin-left":-now*num*(w_li+margin_li*2)});
                    btnshow(now,parseInt((lisize+addli)/num),lisize,num);
                }    
            });    
            btnshow(now,parseInt((lisize+addli)/num),lisize,num);        
        }
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三、代码

1、用到图片

2、完整代码

完整代码

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<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8">
<title></title>
<link rel="stylesheet" type="text/css" href="css/style.css">

<script>
window.onresize=function(){
    var winWidth = document.body.clientWidth;
    if(winWidth <=1180){
        body.className="grid-960"; 
    }else  if (winWidth<= 1410){
        body.className="grid-1180"; 
    }else if (winWidth>1410){
        body.className="grid-1410"; 
    }else {
        alert("do not know!");
    }
}
</script>
</head>
<body id="body" class="">
<script>//初始化状态显示样式判断,放在body后面
var winWidth = document.body.clientWidth;
if (winWidth <=1180){
    body.className="grid-960"; 
}else  if (winWidth<= 1410){
    body.className="grid-1180"; 
}else if (winWidth>1410){
    body.className="grid-1410"; 
}else {
    alert("do not know!");
}
</script>
<div class="wapper">
    
    <div class="section">
        <h2 class="title">热门活动</h2>
        <div class="activity" class="movie" id="activity-slide">
            <a href="javascript:void(0)" class="pg_left ps_pre"></a>
            <a href="javascript:void(0)" class="pg_right ps_next" ></a>
            <ul class="clearfix">
                <li><a href="javascript:;"><img src="images/activity01-1410.jpg"></a></li>
                <li><a href="javascript:;"><img src="images/activity02-1410.jpg"></a></li>
                <li><a href="javascript:;"><img src="images/activity03-1410.jpg"></a></li>
                <li><a href="javascript:;"><img src="images/activity03-1410.jpg"></a></li>
                <li><a href="javascript:;"><img src="images/activity02-1410.jpg"></a></li>
            </ul>
        </div>
    </div>

</div>


</body>
</html>
<script src="http://code.jquery.com/jquery-latest.js"></script>
<script>
//首页图片滚动切换
(function($){
    $.photolist=function(a){        
        var w_li = a.find("li").width();
        var h_li = a.find("li").height();
        var margin_li=parseInt(a.find("li").css("marginLeft"));
        var now = 0;
        var num = 0;
        var addli = 0;
        var lisize = a.find("ul li").size();
        var htmlall = a.find("ul").html();
        
        //判断每次滚动数量
        /*
        var w_body = $("body").width();
        if(w_body <=1170){
            var num = 3;
        }else if(w_body<= 1380){
            var num = 4;
        }else if(w_body>1380){
            var num = 5;
        }
        */
        var num=3;
        
        //判断需要添加的li节点数量
        var reminder=lisize%num;
        if(lisize%num!=0){addli = num-reminder;}
        else{addli = 0;}
        addlist();
        //点击滚动事件
        photoscroll();
        
        $(window).resize(function(){
            //location.reload();
            now = 0;
            addli = 0;
            a.find("ul").html(htmlall);//html内容还原初始值
            a.find(".ps_next").show();//按钮样式初始化
            a.find(".ps_pre").hide();
            //判断每次滚动数量
            /*
            var w_body = $("body").width();
            if(w_body <=1170){
                var num = 3;
            }else if(w_body<= 1380){
                var num = 4;
            }else if(w_body>1380){
                var num = 5;
            }
            */
            var num=3;
            //判断需要添加的li节点数量
            var reminder=lisize%num;
            if(lisize%num!=0){addli = num-reminder;}
            else{addli = 0;}
            addlist();
            w_li = a.find("li").width();
            margin_li=parseInt(a.find("li").css("marginLeft"));
            a.find("ul").css({"width":(w_li+margin_li*2)*(lisize+addli)});
            a.find("ul").animate({"margin-left":0});//ul位置还原
            btnshow(now,parseInt((lisize+addli)/num),lisize,num);
        });
        
        
        function addlist(){
            for(i=0;i<addli;i++){
                var html = a.find("ul li").eq(i).html();
                a.find("ul").append("<li>"+html+"</li>");    
            }
            a.find("ul").css({"width":(w_li+margin_li*2)*(lisize+addli)});
            //console.log(a.find("ul li").size());
        }
        function photoscroll(){
            a.find(".ps_pre").on("click",function(){//console.log(num);    
                now--;
                if(now >= 0){                  
                    a.find("ul").animate({"margin-left":-now*num*(w_li+margin_li*2)});
                    btnshow(now,parseInt((lisize+addli)/num),lisize,num);
                }
            });

            a.find(".ps_next").on("click",function(){//console.log(num);    
                now++;
                if(now < (lisize+addli)/num){    
                    a.find("ul").animate({"margin-left":-now*num*(w_li+margin_li*2)});
                    btnshow(now,parseInt((lisize+addli)/num),lisize,num);
                }    
            });    
            btnshow(now,parseInt((lisize+addli)/num),lisize,num);        
        }
        /***
        参数说明:
        now:当前是第几组,默认是0
        c:总共有几组
        d:初始化时li的个数
        e:每组显示li个数
        ***/
        function btnshow(now,c,d,e){
            if(d<=e){//如果初始化时li的个数小于一组要显示的数,则不显示pre和next按钮
                a.find(".ps_next").hide();
                a.find(".ps_pre").hide();
            }else if(now==0){//初始化now=0,显示第一组,只显示next
                a.find(".ps_next").show();
                a.find(".ps_pre").hide();    
            }else if(now==c-1){//显示到最后一组,只显示pre
                a.find(".ps_next").hide();
                a.find(".ps_pre").show();    
            }else{//显示中间组,pre和next都需要显示
                a.find(".ps_next").show();
                a.find(".ps_pre").show();
            }
        }
        
    }
})(jQuery); 
$.photolist($("#activity-slide"));
</script>
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css部分:

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@charset "utf-8";
body, div, h1, h2, h3, h4, h5, h6, hr, p, blockquote, dl, dt, dd, ul, ol, li, pre, code, form, fieldset, legend, button, textarea, table, tbody, tfoot, thead, th, td, article, aside, dialog, figure, footer, header, hgroup, menu, nav, section, time, mark, audio, video { margin: 0; padding: 0; outline:nonebackground:transparent;
}
article, aside, dialog, figure, footer, header, hgroup, nav, section { display: block; }
body, button, input, select, textarea { font: 12px/1.5 arial, \5b8b\4f53, sans-serif; }
h1, h2, h3, h4, h5, h6, button, input, select, textarea { font-size: 100%; outline: none }
address, cite, dfn, em, var { font-style: normal; }
code, kbd, pre, samp { font-family: courier new, courier, monospace; }
small { font-size: 12px; }
ul, ol, li { list-style: none; }
img { border: none; }
a { text-decoration: none; outline: thin none; }
a:hover { text-decoration: underline; }
table { border-collapse: collapse; border-spacing: 0; }
.clear { clear: both; }
.clearfix:after { visibility: hidden; display: block; font-size: 0; content: " "; clear: both; height: 0; }
html { -webkit-text-size-adjust: none; }
body { font: 12px/1.5 \5FAE\8F6F\96C5\9ED1, tahoma, arial, \5b8b\4f53, sans-serif; }





.grid-960 .wapper { width: 100%; min-width:960px;height: auto; margin: 0 auto; background: url(../images/bg-body-960.jpg) no-repeat center top; }
.grid-1180 .wapper { width: 100%; min-width:1180px;height: auto; margin: 0 auto; background: url(../images/bg-body-1180.jpg) no-repeat center top; }
.grid-1410 .wapper { width: 100%; min-width:1410px;height: auto; margin: 0 auto; background: url(../images/bg-body-1410.jpg) no-repeat center top; }

/*热门活动*/
.grid-960 .section { width: 960px;  margin: 0 auto;background-color:#eaf2ff; }
.grid-1180 .section { width: 1180px;  margin: 0 auto;background-color:#eaf2ff;}
.grid-1410 .section { width: 1410px;  margin: 0 auto;background-color:#eaf2ff;}

.title{padding:0 102px;height:70px;line-height:70px;font-size:24px;font-weight:normal;color:#fff;text-shadow: 0 3px #df2828, 3px 0 #df2828;background:#cc2223 url(../images/bg-title.jpg) no-repeat left top;}

.viewall:hover{text-decoration:none;}
.viewall{font-size:18px;;color:#fff;text-shadow: 0 3px #df2828, 3px 0 #df2828;float:right;}

.grid-1410 .title {padding:0 116px;background-image:url(../images/bg-title-1410.jpg);}

.grid-960 .contentwrap{width:800px;margin:0 auto;}
.grid-1180 .contentwrap{width:980px;margin:0 auto;}
.grid-1410 .contentwrap{width:1180px;margin:0 auto;}

.grid-960 .activity{width:826px;height:152px;overflow:hidden;margin:0 auto;position:relative;}
.grid-1180 .activity{width:1020px;height:192px;overflow:hidden;margin:0 auto;position:relative;}
.grid-1410 .activity{width:1230px;height:232px;overflow:hidden;margin:0 auto;position:relative;}

.grid-960 .activity ul{height:152px;overflow:hidden;}
.grid-1180 .activity ul{height:192px;overflow:hidden;}
.grid-1410 .activity ul{height:232px;overflow:hidden;}

.activity li img{display:block;width:100%;height:100%;}
.activity li{display:block;float:left;}

.grid-960 .activity li{width:250px;height:125px;overflow:hidden;margin:12px;}
.grid-1180 .activity li{width:300px;height:150px;overflow:hidden;margin:20px;}
.grid-1410 .activity li{width:360px;height:180px;overflow:hidden;margin:25px;}
/*js切换*/
.pg_left,.pg_right {position: absolute;z-index: 999;width: 35px;height: 50px;overflow: hidden;}
.pg_right {background: transparent url(../images/pg_right.png) no-repeat scroll 5px 7px;}
.pg_right:hover {background: transparent url(../images/hover.png) no-repeat scroll 0 0;}
.grid-960 .pg_right{top:75px;right:16px;margin-top:-25px;}
.grid-1180 .pg_right{top:95px;right:20px;margin-top:-25px;}
.grid-1410 .pg_right{top:115px;right:25px;margin-top:-25px;}

.pg_left {background: transparent url(../images/pg_left.png) no-repeat scroll 5px 7px;}
.pg_left:hover {background: transparent url(../images/hover.png) no-repeat scroll right 0;}
.grid-960 .pg_left{top:75px;left:13px;margin-top:-25px;}
.grid-1180 .pg_left{top:95px;left:20px;margin-top:-25px;}
.grid-1410 .pg_left{top:115px;left:25px;margin-top:-25px;}
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