Stretch list items to 100% width of container

Question

I'm using bootstrap 3 and trying to imitate metro ui's stepper plugin. I am trying to put left values using jQuery, so that my list items are evenly spaced and take up 100% of the container, but console shows all values are 0. My code:

$(document).ready(function () {

    steps = $(".stepped li"),
    element_width = $(".stepped li").width(),
    steps_length = steps.length - 1,
    step_width = $(steps[0]).width();

    $.each(steps, function (i, step) {
        var left = i == 0 ? 0 : (element_width - step_width) / steps_length * i;

        console.log(steps);
        $(step).animate({
            left: left
        });
    });

});

I can't find what I am doing wrong, all left values are returning 0px. Here's the link to the plugin that I'm trying to imitate: http://tinyurl.com/o6sld95. The list is a simple unordered list.

<ul class="stepped">
    <li class="complete">1</li>
    <li class="complete">2</li>
    <li class="current">3</li>
    <li>4</li>
    <li>5</li>
    <li>6</li>
</ul>

Answer 1

Change element_width = $(".stepped li").width() to element_width = $(".stepped").width().

You currently are getting the width of the li item twice and assigning it to both element_width and step_width, so when you subtract them you get 0.

JSFiddle

Answer 2

Here is a plain css solution, if that is interesting for you: http://jsfiddle.net/u3w0qfaz/1/

The first version is using transition of the width of the parent container to simulate the desired effect:

ul.stepped {
    display: flex;
    list-style: none;
    flex-wrap: nowrap;
    flex-direction: row;
    transition-duration: 1s;
    width: 1px;
}
ul.stepped li {
    flex: 1 1 auto;
}
ul.stepped.go {
    width: 100%;
}

Here is another version which is using transform to have a scaling effect on the items: http://jsfiddle.net/u3w0qfaz/

ul.stepped
{
    /*...*/
    transform: scaleX(0);
    transform-origin: left;
}

ul.stepped.go
{
   transform: scaleX(1); 
}

Answer 3

If you're using Bootstrap three you could use the Justified Button Nav .

Bootstrap 3 + 1 CSS:

ul{
  -webkit-padding-start: 0px;
}


<ul class="stepped btn-group btn-group-justified">
  <li class="complete btn-group">1</li>
  <li class="complete btn-group">2</li>
  <li class="current btn-group">3</li>
  <li class="btn-group">4</li>
  <li class="btn-group">5</li>
  <li class="btn-group">6</li>
</ul>

JsFiddle Example.

There is no need for jQuery at all unless you need to support browsers that are only CSS 2.x.

Or pure CSS + HTML (pretty much how Bootstrap 3 does it)

.stepped{
    padding: 0;
    display: block;
    width: 100%;
}

.stepped > li {
    display: table-cell;
    border: 1px solid black;
    width: 1%;
}

<ul class="stepped">
  <li class="complete">1</li>
  <li class="complete">2</li>
  <li class="current">3</li>
  <li>4</li>
  <li>5</li>
  <li>6</li>
</ul>

JS Fiddle Example