【发布时间】：2013-06-15 15:23:20
【问题描述】：
我有一个带有许多文本区域的网络应用程序，如果您愿意，可以添加更多内容。
当您将焦点从一个 textarea 转移到另一个 textarea 时，焦点所在的动画会变大，其余的会缩小。
当页面加载时，它会完美地处理 html 文件中最初四个框的动画，但是当您单击按钮添加更多文本区域时，动画无法容纳这些新元素...也就是说，除非您放置函数中的初始查询，并从绑定到按钮的 addelement 函数中调用该函数。
但是！当您这样做时，它会查询与您添加新元素一样多的次数。因此，如果您快速添加（例如 10 个）新的 textarea，那么下次您将注意力放在任何 textarea 上时，查询会运行 10 次。
是我的设计问题还是 jQueries 实现问题？如果是前者，我该如何设计它，如果是后者，我该如何解决？
我已经尝试将代码缩减到相关的部分...我尝试了从焦点和模糊到按键的所有方法，最新的是点击。
html::
<html>
<head>
<link rel="stylesheet" type="text/css" href="./sty/sty.css" />
<script src="./jquery.js"></script>
<script>
$().ready(function() {
var $scrollingDiv = $("#scrollingDiv");
$(window).scroll(function(){
$scrollingDiv
.stop()
//.animate({"marginTop": ($(window).scrollTop() + 30) + "px"}, "slow" );
.animate({"marginTop": ($(window).scrollTop() + 30) + "px"}, "fast" );
});
});
</script>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>boxdforstacks</title>
</head>
<body>
<div class="grid">
<div class="col-left" id="left">
<div class="module" id="scrollingDiv">
<input type="button" value="add" onclick="addele()" />
<input type="button" value="rem" onclick="remele()" />
<p class="display">The value of the text input is: </p>
</div>
</div> <!--div class="col-left"-->
<div class="col-midd">
<div class="module" id="top">
<p>boxa</p>
<textarea class="tecksd" placeholder="begin typing here..." id="boxa" ></textarea>
<p>boxb</p>
<textarea class="tecksd" placeholder="begin typing here..." id="boxb"></textarea>
<p>boxc</p>
<textarea class="tecksd" placeholder="begin typing here..." id="boxc"></textarea>
<p>boxd</p>
<textarea class="tecksd" placeholder="begin typing here..." id="boxd"></textarea>
</div>
</div> <!--div class="col-midd"-->
</div> <!--div class="grid"-->
</body>
</html>
<script type="text/javascript" src="boxd.js"></script>
js:
function onit(){
$('textarea').on('keyup change', function() {
$('p.display').text('The value of the text input is: ' + $(this).val());
});
}
$('textarea').on("click",function(){
//alert(this.id.substring(0,3));
if ( this.id.substring(0,3) == 'box' ){
$('textarea').animate({ height: "51" }, 1000);
$(this).animate({ height: "409" }, 1000);
} else {
$('textarea').animate({ height: "51" }, 1000);
}
}
);
var boxfoc="";
var olebox="";
var numb = 0;
onit();
function addele() {
var tops = document.getElementById('top');
var num = numb + 1;
var romu = romanise(num);
var newbox = document.createElement('textarea');
var newboxid = 'box'+num;
newbox.setAttribute('id',newboxid);
newbox.setAttribute('class','tecksd');
newbox.setAttribute('placeholder','('+romu+')');
tops.appendChild(newbox);
numb = num;
onit();
} //addele(), add element
function remele(){
var tops = document.getElementById('top');
var boxdone = document.getElementById(boxfoc);
tops.removeChild(boxdone);
} // remele(), remove element
function romanise (num) {
if (!+num)
return false;
var digits = String(+num).split(""),
key = ["","c","cc","ccc","cd","d","dc","dcc","dccc","cm",
"","x","xx","xxx","xl","l","lx","lxx","lxxx","xc",
"","i","ii","iii","iv","v","vi","vii","viii","ix"],
roman = "",
i = 3;
while (i--)
roman = (key[+digits.pop() + (i * 10)] || "") + roman;
return Array(+digits.join("") + 1).join("M") + roman;
} // romanise(), turn numbers into roman numerals
css：
.tecksd {
width: 97%;
height: 51;
resize: none;
outline: none;
border: none;
font-family: "Lucida Console", Monaco, monospace;
font-weight: 100;
font-size: 70%;
background: white;
/* box-shadow: 1px 2px 7px 1px #0044FF;*/
}
.tecksded {
width: 97%;
resize: none;
outline: none;
border: none;
overflow: auto;
position: relative;
font-family: "Lucida Console", Monaco, monospace;
font-weight: 100;
font-size: 70%;
background: white;
/* box-shadow: 1px 2px 7px #FFDD00;*/
}
/*#postcomp {
width: 500px;
}*/
* {
@include box-sizing(border-box);
}
$pad: 20px;
.grid {
background: white;
margin: 0 0 $pad 0;
&:after {
/* Or @extend clearfix */
content: "";
display: table;
clear: both;
}
}
[class*='col-'] {
float: left;
padding-right: $pad;
.grid &:last-of-type {
padding-right: 0;
}
}
.col-left {
width: 13%;
}
.col-midd {
width: 43%;
}
.col-rght {
width: 43%;
}
.module {
padding: $pad;
}
/* Opt-in outside padding */
.grid-pad {
padding: $pad 0 $pad $pad;
[class*='col-']:last-of-type {
padding-right: $pad;
}
}
body {
padding: 10px 50px 200px;
background: #FFFFFF;
background-image: url('./backgrid.png');
}
h1 {
color: black;
font-size: 11px;
font-family: "Lucida Console", Monaco, monospace;
font-weight: 100;
}
p {
color: white;
font-size: 11px;
font-family: "Lucida Console", Monaco, monospace;
font-weight: 100;
}
【问题讨论】：
标签： javascript jquery web-applications user-interface web