Set width of list items to fill unordered list

Question

So I have a horizontal unordered list with a set width. Inside, I have a dynamic number of list items. It could be 2 items, or 6 - it depends on several factors.

I'd like to be able to set the width of each list item so that they fill the entire width of the ul, no matter how many items are inside. So if there was 1 list item, it's width would be 100%; 2, and they would both be 50%, and so on.

Here's my HTML and CSS:

ul
{
    width: 300px;
    height: 50px;
    background-color: #000000;
    list-style: none;
    margin: 0;
    padding: 0;
}

li
{
    float: left;
    height: 50px;
    background-color: #4265CE;
    margin: 0;
    padding: 0;
}

<ul>
    <li>Item 1</li>
    <li>Item 2</li>
    <li>Item 3</li>
    <li>Item 4</li>
</ul>

Here it is in jFiddle: http://jsfiddle.net/vDVvm/3/

Is there a way to do this with CSS, or will I have to use jQuery?

Answer 1

No way with pure CSS, I'm afraid.

Edit: Most proper jQuery solution i can think of: http://jsfiddle.net/vDVvm/8/

(function( $ ){
  $.fn.autowidth = function() {
    return this.each(function() {        
        $('li', this).css({'width' : (100 / $('li', this).length) + '%'})
    });
  };
})( jQuery );

$(document).ready(function(){
    $('.fill-me').autowidth();    
});

Keep in mind though, that whenever (100 % number_of_lis !== 0), you're gonna be running into some nasty problems with rounding errors.

Answer 2

A solution without JavaScript.

ul
{
    width: 300px;
    height: 50px;
    background-color: #000000;
    list-style: none;
    margin: 0;
    padding: 0;
    display: table;
}

li
{
    height: 50px;
    background-color: #4265CE;
    margin: 0;
    padding: 0;
    display: table-cell;
}

http://jsfiddle.net/vDVvm/5/

It may be not cross browser enough, however.