Alter existing jQuery to make span placeholder

I have some jQuery that p开发者_开发知识库rovides a placeholder as long as my <label for=""> matches the input name and ID. However, that's not the case so I've decided to just use a <span> for the placeholder instead. Can someone help alter my jQuery to make the <span> class "holder" I'm using work? The goal is to have the placeholder stay on focus, disappear when input exists, then reappear if the input disappears.

Here's the HTML I'm using:

<div id="placeholder">
  <span class="holder">This is the placeholder...</span>
  <%= f.text_area :body, :id =>"Placeholder" %>
</div>

And my current jQuery:

$(document).ready(function() {
    $('textarea').keyup(function() {
        if ($(this).val().length) {
            $('label[for="' + $(this).attr('name') + '"]').hide();
        } else {
            $('label[for="' + $(this).attr('name') + '"]').show();
        }
    });
});

Thanks!

---

You want to bind to the focus and blur events and absolutely position the <span> over the <textarea>. Start with some CSS:

#placeholder {
    position: relative;
}

.holder {
    position: absolute;
    top: 2px;
    left: 2px;
    display: none;
}

And then the jQuery:

$('.holder').click(function() {
    $(this).siblings('textarea').focus();
});
$('#Placeholder').focus(function() {
    $(this).siblings('.holder').hide();
});
$('#Placeholder').blur(function() {
    var $this = $(this);
    if($this.val().length == 0)
        $(this).siblings('.holder').show();
});
$('#Placeholder').blur();

The final $('#Placeholder').blur() call is there to initialize the state of the <span> so that it will be in the right state if the <textarea> starts out with content.

And a quick demo: http://jsfiddle.net/ambiguous/PLrf3/1/

BTW, having id="placeholder" and id="Placeholder" in the same page might lead to some confusion. You would be better off choosing a standard scheme (camelCase, words-and-hyphens, or whatever) for your id attributes and sticking to it. Just a case difference might be confusing and might look like a typo.

---

Something like this should work:

$(function() {
    $("span.holder + textarea").keyup(function() {
        if($(this).val().length) {
            $(this).prev('span.holder').hide();
        } else {
            $(this).prev('span.holder').show();
        }
    });        
});

This should work for all textareas on page if they have span.holder preceding them.