.find doesn't work in jquery 1.4.2 and I can't figure out how to support it
Question
I can't figure out how to write my code backwards to support jQuery 1.4.2. So I am perplexed trying to support older library files.
var n = this;
e(document).ready(function () {
var r = e("body").find(n);
r.attr("placeholder", t);
r.val(t);
n.focus(function () {
e(this).val("")
}).blur(function () {
var r = e(n);
if (r.val() == "") r.val(t)
})
})
4 answers
solution1
0 2013-08-19 19:56:06
Yes, that would be correct. The .find() function was added in 1.6. You could upgrade jQuery or use the .find() using the CSS selector.
If you have the elements with unique .id elements, you could just change your .find function to call that:
.find('#' + n.id)
Another option, since you have 'this', is that you could just use the basic $(this):
var r = $(this);
Or, for your code r = e(this);
solution2
0 2013-08-19 19:59:26
This might not be the most elegant solution, but you could check if the find function exists, and then add it to the jquery object if it does not.
Something like
if (!$.find) {
$.fn.find = function () {
// find function definition
};
}
edit: a better conditional:
var version = $.fn.jquery.split('.');
if (version[0] < 2 && version[1] <= 6 && version[2] < 4)
last edit: since jsfiddle doesn't have less than 1.6.4 jquery, i can't test this to verify, but I pulled the find function from google's cdn jquery 1.6.4, so the complete monkeypatch would be:
var version = $.fn.jquery.split('.');
if (version[0] < 2 && version[1] <= 6 && version[2] < 4) {
$.find = function( expr, context, isXML ) {
var set;
if ( !expr ) {
return [];
}
for ( var i = 0, l = Expr.order.length; i < l; i++ ) {
var match,
type = Expr.order[i];
if ( (match = Expr.leftMatch[ type ].exec( expr )) ) {
var left = match[1];
match.splice( 1, 1 );
if ( left.substr( left.length - 1 ) !== "\\" ) {
match[1] = (match[1] || "").replace( rBackslash, "" );
set = Expr.find[ type ]( match, context, isXML );
if ( set != null ) {
expr = expr.replace( Expr.match[ type ], "" );
break;
}
}
}
}
if ( !set ) {
set = typeof context.getElementsByTagName !== "undefined" ?
context.getElementsByTagName( "*" ) :
[];
}
return { set: set, expr: expr };
};
solution3
0 2013-08-19 20:03:21
Are you sure of this ? I have just binned out one example using 1.4.2 for find and it's working properly .
HTML:
<!DOCTYPE html>
<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
<meta charset=utf-8 />
<title>JS Bin</title>
</head>
<body id='bd'>
<ul class="level-1">
<li class="item-i">I</li>
<li class="item-ii">II
<ul class="level-2">
<li class="item-a">A</li>
<li class="item-b">B
<ul class="level-3">
<li class="item-1">1</li>
<li class="item-2">2</li>
<li class="item-3">3</li>
</ul>
</li>
<li class="item-c">C</li>
</ul>
</li>
<li class="item-iii">III</li>
</ul>
</body>
</html>
JS:
$('li.item-ii').find('li').css('background-color', 'red');
Find the bin here : http://jsbin.com/INonAYo/1/edit
solution4
0 ACCPTED 2013-08-19 20:34:12
You're overcomplicating your code. First, you don't need to use $(document).ready() inside of a plugin, you can let the developer using the plugin take care of that. Next, inside of a plugin, this is a jQuery object containing the selected elements. You should iterate over them then act on each one individually.
(function ($) {
$.fn.labelfixer = function (t) {
return this.each(function(){
var $this = $(this);
$this.attr("placeholder",t);
this.value = t;
$this.focus(function(){
if (this.value == t) {
this.value = "";
}
});
$this.blur(function(){
if (this.value == "") {
this.value = t;
}
});
});
};
})(jQuery);
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