HTML5 serial port access

2015 update: the flexbox approach

There are two other answers briefly mentioning flexbox; however, that was more than two years ago, and they don't provide any examples. The specification for flexbox has definitely settled now.

Note: Though CSS Flexible Boxes Layout specification is at the Candidate Recommendation stage, not all browsers have implemented it. WebKit implementation must be prefixed with -webkit-; Internet Explorer implements an old version of the spec, prefixed with -ms-; Opera 12.10 implements the latest version of the spec, unprefixed. See the compatibility table on each property for an up-to-date compatibility status.

(taken from https://developer.mozilla.org/en-US/docs/Web/Guide/CSS/Flexible_boxes)

All major browsers and IE11+ support Flexbox. For IE 10 or older, you can use the FlexieJS shim.

To check current support you can also see here: http://caniuse.com/#feat=flexbox

Working example

With flexbox you can easily switch between any of your rows or columns either having fixed dimensions, content-sized dimensions or remaining-space dimensions. In my example I have set the header to snap to its content (as per the OPs question), I've added a footer to show how to add a fixed-height region and then set the content area to fill up the remaining space.

html,
body {
  height: 100%;
  margin: 0;
}

.box {
  display: flex;
  flex-flow: column;
  height: 100%;
}

.box .row {
  border: 1px dotted grey;
}

.box .row.header {
  flex: 0 1 auto;
  /* The above is shorthand for:
  flex-grow: 0,
  flex-shrink: 1,
  flex-basis: auto
  */
}

.box .row.content {
  flex: 1 1 auto;
}

.box .row.footer {
  flex: 0 1 40px;
}

<!-- Obviously, you could use HTML5 tags like `header`, `footer` and `section` -->

<div class="box">
  <div class="row header">
    <p><b>header</b>
      <br />
      <br />(sized to content)</p>
  </div>
  <div class="row content">
    <p>
      <b>content</b>
      (fills remaining space)
    </p>
  </div>
  <div class="row footer">
    <p><b>footer</b> (fixed height)</p>
  </div>
</div>

In the CSS above, the flex property shorthands the flex-grow, flex-shrink, and flex-basis properties to establish the flexibility of the flex items. Mozilla has a good introduction to the flexible boxes model.

Here's your example in the "one" line.

this.$OuterDiv = $('<div></div>')
    .hide()
    .append($('<table></table>')
        .attr({ cellSpacing : 0 })
        .addClass("text")
    )
;

Update: I thought I'd update this post since it still gets quite a bit of traffic. In the comments below there's some discussion about $("<div>") vs $("<div></div>") vs $(document.createElement('div')) as a way of creating new elements, and which is "best".

I put together a small benchmark, and here are roughly the results of repeating the above options 100,000 times:

jQuery 1.4, 1.5, 1.6

               Chrome 11  Firefox 4   IE9
<div>            440ms      640ms    460ms
<div></div>      420ms      650ms    480ms
createElement    100ms      180ms    300ms

jQuery 1.3

                Chrome 11
<div>             770ms
<div></div>      3800ms
createElement     100ms

jQuery 1.2

                Chrome 11
<div>            3500ms
<div></div>      3500ms
createElement     100ms

I think it's no big surprise, but document.createElement is the fastest method. Of course, before you go off and start refactoring your entire codebase, remember that the differences we're talking about here (in all but the archaic versions of jQuery) equate to about an extra 3 milliseconds per thousand elements.

Update 2

Updated for jQuery 1.7.2 and put the benchmark on JSBen.ch which is probably a bit more scientific than my primitive benchmarks, plus it can be crowdsourced now!

http://jsben.ch/#/ARUtz