Colin Cochrane

Colin Cochrane is a Software Developer based in Victoria, BC specializing in C#, PowerShell, Web Development and DevOps.

The Worlds Most Appropriate Image Alt Attribute

As all good web developers know, accessibility is a very important consideration with an ever increasing proportion of the population that is old and decrepit. One of the more important accessibility features is the image alt attribute that is used to describe an image for visually impaired users. It's always nice to find a site that has accessbility in mind by providing good descriptions of an image within the alt attribute text.

 This particular example has got to be the best I have ever come across, and is an inspired choice of descriptive text that makes it clear to the elderly user what shenanigans are going on within the picture.

 

You didn't think I could top that did you?


This interesting commentary on modern family life within the UK can be found here, http://www.dailymail.co.uk/pages/live/femail/article.html?in_article_id=514809&in_page_id=1879.

 Note, unfortunately the alt text has been changed since this screenshot was taken. The good SEO strategy of a related high value keyword in the picture filename remains, however.

Using CSS To Create Two Common HTML Border Effects

Seperating the style from the markup of a web document is generally a painless, if sometimes time-consuming, task.  In many cases however, the process can have some added speed-bumps; most notably when the original HTML is using an infamous table-based layout.  The two most common speedbumps when dealing with table-based layouts and styling are recreating the classic borderless table and keeping the default table border appearance.

The appearance of these two kinds of table are as follows 

Default Border

1 2
3 4

Borderless

1 2
3 4

The markup for these two tables looks like:

[code:html]

<!--Default Border -->
<table border="1">
<tbody>
<tr>
<td>1</td>
<td>2</td>
</tr>
<tr>
<td>3</td>
<td>4</td>
</tr>
</tbody>
</table>
<!-- Borderless -->
<table border="0" cellspacing="0" cellpadding="0">
<tbody>
<tr>
<td>1</td>
<td>2</td>
</tr>
<tr>
<td>3</td>
<td>4</td>
</tr>
</tbody>
</table>

[/code]

If you want to get the same effects while losing the HTML attributes you can use the folllow CSS:

Default Border

[code:html]

table{border-spacing:0px;border:solid 1px #8D8D8D;width:130px;}
table td{
border:solid 1px #C0C0C0;
border-bottom:solid 1px #8D8D8D;
border-left:solid 1px #8D8D8D;
display:table-cell;
margin:0;
padding:0;}

[/code]


Borderless

[code:html]

table{border:none;border-collapse:collapse;}
table td{padding:0;margin:0;}

[/code]

Duplicating the default table border look requires extra rules in its style definition because the default border contains two shades so the border-color values must be set accordingly. 

That is the basic method to replicating HTML table effects with CSS that are usually created with HTML attributes.

7 Firefox Add Ons For Web Developers

Firefox add-ons can be one of the best set of tools a web developer can have but with so many out there it can be hard to decide on which ones are the best for you.  I was reluctant to post this at first, given the countless other blogs out their who have posted their own add-on lists, but felt this would be of value for those looking for recommendations that weren't posted 2-3 years ago.  I avoided going for the "Top 841 Add Ons Every Web Developer Must Have!!!!" angle, as this isn't a top list.  It's simply a list of my personal favourites because, as a guy who's known around the office for having too many add-ons installed for Firefox, I've definitely used a lot of add-ons, some which were fanstastic, and some which left something to be desired.  Over time I managed to pare down my pile of add-ons in to a core set that all save me a considerable amount of time, and also share the same basic qualities:

  1. Easy to Use
  2. Not Obtrusive
  3. Light-Weight
  4. Accurate

Ease of use is important to saving time (an add-on isn't going to increase productivity if it takes just as long to figure out how to use it, configure it, or even just to use it).  Not being obtrusive is important because I want my add-ons to be un-noticable other than a toolbar or icon unless I actively want to utlilize it, and this ties in with being light-weight, as a light-weight add-on is not going to cause any decreases in performance.  Finally, accuracy is imperitive because I have to be able to trust what information the add-on is providing me with.

With those qualities explained, I'll get on to the list.

1) Firebug

For web development and/or design if you are going to install one add-on, this is the one.  Firebug lets you view, edit, debug and monitor HTML, CSS and JavaScript live on any web page.  I use Firebug extensively every day to test layout changes before I make them, to debug script errors, navigate through a page's markup with ease, monitor all the HTTP requests made for a given page, and more.  It also has some incredibly useful features like a diagram that shows all the measurements for dimension, margin, padding, border, etc... for a selected element, a list of applied styles for a selected element, and the "inspect" feature that lets you simply click on the part of a web page you want to analyze and have Firebug automatically get all the details on it for you.

 



2) Web Developer

Web Developer is an add-on that provides a toolbar and menu that gives you access to a host of different development tools.  Just one of the 12 toolbar buttons gives you the following options:



There are tons of other useful tools included with Web Developer, including some of my personal favourites:

  • Outline different HTML elements (with ability to display element type and custom outline colour)
  • Show/hide/outline images with oversized dimensions, missing alt attributes, adjusted dimensions, missing dimensions, etc
  • Show image paths, alt and title attributes, sizes
  • Disable javascript
  • Disable CSS styles (external, interal, inline, etc..) 

3) Greasemonkey

One of the most popular add-ons out there, Greasemonkey simply lets you run custom JavaScript against any page you want.  There are thousands of Greasemonkey scripts out there for those who don't want to create their own, offering enhancements such as numbering search results in Google, MSN and Yahoo, killing pop-up ads, and pretty much anything else you could think of.

4) HTML Validator

A must have if you care about W3C validation.  HTML Validator displays an icon in the bottom of your browser indicating if the current page validates against its DOCTYPE, as well as the number of errors and warnings.  You can configure the validation method it uses (HTML Tidy, or SGML which is used by the W3C Markup Validation Service), and it also displays a list of errors and highlights them in when you view the page's source.

5) MeasureIt

Simple and easy-to use, MeasureIt is an add-on that, when activated, displays an overlay where you can drag and position a dynamic ruler so you can measure dimensions on a web page.



6) Session Manager

Session Manager is an incredibly useful add-on that tracks your Firefox sessions and allows you reload older sessions or recover a crashed session.  If you're like me and usually have the same websites opened in different tabs, this add-on will make your life a lot easier.

7) QuickRestart

QuickRestart is a simple and convenient add-on that simply adds a button to your toolbar that restarts Firefox, just like when you install an add-on or upgrade.

Hopefully you will find these add-ons as useful as I have.  I'll also be posting a list of useful add-ons for Internet Explorer later this week as well.  I encourage everyone to comment with your own recommendations for Firefox add-ons that you find useful for web development.

 

Reducing Code Bloat - Or How To Cut Your HTML Size In Half

When it comes to designing and developing a web site the load time is one consideration that is often ignored, or is an afterthought once the majority of the design and structure is in place.  While high-speed internet connections are becoming increasingly common there are still a significant portion of web users out there with 56k connections, and even those with broadband connections aren't guaranteed to have a fast connection to your particular server.  Every second that a user has to wait to download your content is increasing the chance of that user deciding to move on.

Attempting to reduce the size of a web page is usually restricted to compressing larger images and optimizing them for web use.  This is a necessary step to managing page size, but there is another important factor that can significantly reduce the size of a page to improve download times: code bloat, or more specifically, (x)HTML code bloat.  Getting rid of that code bloat means less actual bytes to be downloaded by clients, as well as captilizing on what the client has already downloaded.  Unfortunately this is an option that tends to be ignored due to the perceived loss of time spent combing through markup to cut out the chaff, despite the fact that clean, efficient markup with well-planned style definitions will save countless hours when it comes to upkeep and maintenance.

To demonstrate the difference between a bloated page and one with efficient markup I created two basic pages.  One uses tables, font tags, HTML style attributes and so forth to control the structure and look of the page, while the other uses minimal markup with an external stylesheet.

1) Bloated Page

[code:html]

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>This Tag Soup Is Really Thick</title>
<meta name="description" content="The end result of lazy web page design resulting in a bloated mess of HTML.">
<meta name="keywords" content="tag soup, messy html, bloated html">
</head>
<body>
<center>
  <table width=700 height=800 bgcolor="gainsboro" border=0 cellpadding=0 cellspacing=0>
    <tr>
      <td valign=top width=150><table align=center border=0 cellpadding=0 cellspacing=0>
          <tr>
            <td align="left"><a href="#home" title="Not a real link"><font color="#4FB322" size="3" face="Geneva, Arial, Helvetica, sans-serif">Home Page</font></a></td>
          </tr>
          <tr>
            <td align="left"><a href="#about" title="Not a real link"><font color="#4FB322" size="3" face="Geneva, Arial, Helvetica, sans-serif">About Me</font></a></td>
          </tr>
          <tr>
            <td align="left"><a href="#links" title="Not a real link"><font color="#4FB322" size="3" face="Geneva, Arial, Helvetica, sans-serif">Links</font></a></td>
          </tr>
        </table></td>
      <td valign=top><table>
          <tr>
            <td align="center" height=64><h1><font color="red" face="Geneva, Arial, Helvetica, sans-serif">Welcome to My Site!</font></h1></td>
          </tr>
          <tr>
            <td align="left"><font color="#FFFFFF" size="3" face="Geneva, Arial, Helvetica, sans-serif">Isn&acute;t it surprisingly ugly and bland?</font></td>
          </tr>
          <tr>
            <td align="left"><font color="#FFFFFF" size="3" face="Geneva, Arial, Helvetica, sans-serif">Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Fusce est. Maecenas pharetra nibh vel turpis molestie gravida. Integer convallis odio eu nulla. Vivamus eget turpis eu neque dignissim dignissim. Fusce vel erat ut turpis pharetra molestie. Cras sollicitudin consequat sem. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Maecenas augue diam, sagittis eget, cursus at, vulputate at, nisl. Etiam scelerisque molestie nibh. Suspendisse ornare dignissim enim. Sed posuere nunc a lectus. Vestibulum luctus, nibh feugiat convallis ornare, lorem neque volutpat risus, a dapibus odio justo at erat. Donec vel lacus id urna luctus tincidunt. Morbi nunc. Donec fringilla sapien nec lectus. Duis at felis a leo porta tempor.</font></td>
          </tr>
          <tr>
            <td align="left"><font color="#FFFFFF" size="3" face="Geneva, Arial, Helvetica, sans-serif">Maecenas malesuada felis id mauris. Ut nibh eros, vestibulum nec, ornare sollicitudin, hendrerit et, ligula. Suspendisse tellus elit, rutrum ut, tempor eget, porta bibendum, magna. Nunc sem dolor, pharetra ut, fermentum in, consequat vitae, velit. Vestibulum in ipsum. Phasellus erat. Sed eget turpis tristique eros cursus gravida. Vestibulum quis pede a libero elementum varius. Nullam feugiat accumsan enim. Aenean nec mi. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae;</font></td>
          </tr>
          <tr>
            <td align="left"><font color="#FFFFFF" size="3" face="Geneva, Arial, Helvetica, sans-serif">Aenean vel neque ac orci sagittis tristique. Phasellus cursus quam a mauris. Donec posuere pede a nisl. Curabitur nec ligula eu nibh accumsan sagittis. Integer lacinia. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos hymenaeos. Praesent tortor dolor, pellentesque eget, fermentum vel, mollis ut, erat. Nullam mollis. Cras rhoncus tellus ut neque. Pellentesque sed ante.</font></td>
          </tr>
          <tr align="left">
            <td><font color="#FFFFFF" size="3" face="Geneva, Arial, Helvetica, sans-serif">Donec at nunc. Nulla elementum porta elit. Donec bibendum. Fusce elit ligula, gravida et, tincidunt et, aliquam sit amet, metus. Nulla id magna. Fusce quis eros. Sed eget justo. Vivamus dictum interdum quam. Curabitur malesuada. Proin id metus. Curabitur feugiat. Nunc in turpis. Cras lobortis lobortis felis. Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Mauris imperdiet aliquet ante. Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</font></td>
          </tr>
          <tr align="left">
            <td><font color="#FFFFFF" size="3" face="Geneva, Arial, Helvetica, sans-serif">Etiam tristique mauris at nibh sodales pretium. In lorem eros, laoreet eget, rhoncus et, lacinia nec, pede. Fusce a quam. Pellentesque vitae lacus. Vivamus commodo. Morbi euismod, ipsum id consectetuer ornare, nisi sem suscipit pede, vel dictum purus mauris eu leo. Proin sodales. Aliquam in pede nec eros aliquet adipiscing. Nulla a purus sed risus ullamcorper tempus. Nunc neque magna, fringilla quis, ullamcorper vitae, placerat sed, orci. Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae;</font></td>
          </tr>
        </table></td>
    </tr>
  </table>
</center>
</body>
</html>

[/code]

2) Cleaned Page

[code:html]

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
    <title>Less Markup, More Content</title>
    <meta name="description" content="The end result of lazy web page design resulting in a bloated mess of HTML.">
    <meta name="keywords" content="tag soup, messy html, bloated html">
    <link href="style.css" rel="stylesheet" type="text/css">
  </head>
  <body>
    <div class="content">
      <ul class="menu">
        <li><a href="#home" title="Not a real link">Home Page</a></li>
        <li><a href="#home" title="Not a real link">About Me</a></li>
        <li><a href="#home" title="Not a real link">Links</a></li>
      </ul>
      <h1>Welcome To My Site!</h1>
      <p>Isn&acute;t it suprisingly ugly and bland?</p>
      <p>Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Fusce est.  Maecenas pharetra nibh vel turpis molestie gravida. Integer convallis  odio eu nulla. Vivamus eget turpis eu neque dignissim dignissim. Fusce  vel erat ut turpis pharetra molestie. Cras sollicitudin consequat sem.  Vestibulum ante ipsum primis in faucibus orci luctus et ultrices  posuere cubiliaCurae; Maecenas augue diam, sagittis eget, cursus at,  vulputate at, nisl. Etiam scelerisque molestie nibh. Suspendisse ornare  dignissim enim. Sed posuere nunc a lectus. Vestibulum luctus, nibh  feugiat convallis ornare, lorem neque volutpat risus, a dapibus odio  justo at erat. Donec vel lacus id urna luctus tincidunt. Morbi nunc.  Donec fringilla sapien nec lectus. Duis at felis a leo porta tempor. </p>
      <p>Maecenas malesuada felis id mauris. Ut nibh eros, vestibulum nec,  ornare sollicitudin, hendrerit et, ligula. Suspendisse tellus elit,  rutrum ut, tempor eget, porta bibendum, magna. Nunc sem dolor, pharetra  ut, fermentum in, consequat vitae, velit. Vestibulum in ipsum.  Phasellus erat. Sed eget turpis tristique eros cursus gravida.  Vestibulum quis pede a libero elementum varius. Nullam feugiat accumsan  enim. Aenean nec mi. Vestibulum ante ipsum primis in faucibus orci  luctus et ultrices posuere cubilia Curae; </p>
      <p>Aenean vel neque ac orci sagittis tristique. Phasellus cursus quam a  mauris. Donec posuere pede a nisl. Curabitur nec ligula eu nibh  accumsan sagittis. Integer lacinia. Class aptent taciti sociosqu ad  litora torquent per conubia nostra, per inceptos hymenaeos. Praesent  tortor dolor, pellentesque eget, fermentum vel, mollis ut, erat. Nullam  mollis. Cras rhoncus tellus ut neque. Pellentesque sed ante. </p>
      <p>Donec at nunc. Nulla elementum porta elit. Donec bibendum. Fusce  elit ligula, gravida et, tincidunt et, aliquam sit amet, metus. Nulla  id magna. Fusce quis eros. Sed eget justo. Vivamus dictum interdum  quam. Curabitur malesuada. Proin id metus. Curabitur feugiat. Nunc in  turpis. Cras lobortis lobortis felis. Pellentesque habitant morbi  tristique senectus et netus et malesuada fames ac turpis egestas.  Mauris imperdiet aliquet ante. Lorem ipsum dolor sit amet, consectetuer  adipiscing elit. </p>
      <p>Etiam tristique mauris at nibh sodales pretium. In lorem eros,  laoreet eget, rhoncus et, lacinia nec, pede. Fusce a quam. Pellentesque  vitae lacus. Vivamus commodo. Morbi euismod, ipsum id consectetuer  ornare, nisi sem suscipit pede, vel dictum purus mauris eu leo. Proin  sodales. Aliquam in pede nec eros aliquet adipiscing. Nulla a purus sed  risus ullamcorper tempus. Nunc neque magna, fringilla quis, ullamcorper  vitae, placerat sed, orci. Pellentesque habitant morbi tristique  senectus et netus et malesuada fames ac turpis egestas. Vestibulum ante  ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; </p>
    </div>
  </body>
</html>

[/code]

External Style Sheet

[code:html]

@charset "utf-8";
body{font:13pt Geneva, Arial, Helvetica, sans-serif;}
.menu{float:left;height:800px;list-style-type:none;width:150px;}
.menu a, .menu a:visited{color:#4FB322;}
.content{background:gainsboro;color:white;margin:auto;position:relative;width:700px;}
h1{color:red;line-height:64px;text-align:center;}
p{margin:4px;}

[/code]

Even in this basic example you can see a fairly dramatic improvement when the excess HTML is trimmed and CSS is used to control style.  The original page is 51 lines, where the cleaned page is only 26 lines, plus 7 lines in the style sheet.  The cleaned page is a third the size of the original (counting the style sheet), and more realistically is actually half the size because the style sheet would be cached by most client browsers and wouldn't be downloaded for every page request.  As far as raw kilobytes it's a difference of 6KB to 4KB, which isn't a particularly exciting difference in this case, but one that is quickly magnified as the length of the page increases.  This is especially true with dynamic applications that pull content from a database, most importantly content such as product listings that utilize the same markup and are repeated multiple times. Fortunately in the case of dynamic pages involving looping procedures that output the same markup with different content, cutting down the bloat can be as easy as a few modifications to those procedures.

Furthermore if you wanted to change, for instance, the font color or the line-height in the original, you would have to modify every font tag and table cell to accomplish that.  Implementing those changes in the second example requires a single modification to the style-sheet.  The time-saved here is once again significantly amplified when considered in a situation with multiple pages (in many cases this can be hundreds or even thousands).

When all is said and done, this isn't meant to be a be-all end-all guide for optimizing your markup because I could write a book and still not cover it all.  Rather it was meant to highlight an aspect of web page performance and optimization that is usually swept under the rug in favour of those that are more directly appreciable such as eye-candy and new features.  While clean markup might not be as "glamourous" as other aspects of web development, it is an important aspect to keeping load time in check and a crucial factor in reducing them amount of time spent maintaining and updating.

Three CSS Roll Over Techniques You Might Not Know About

When it comes to rollover effects in web design the most common way to accomplish the effect has traditionally been with JavaScript:


JavaScript in the HEAD section

[code:html]

<script language="JavaScript">
<!--
// preload images
if (document.images) {
img_on =new Image(); img_on.src ="../images/1.gif";
img_off=new Image(); img_off.src="../images/2.gif";
}
function handleOver() {
if (document.images) document.imgName.src=img_on.src;
}
function handleOut() {
if (document.images) document.imgName.src=img_off.src;
}
//-->
</script>

[/code]


And in the element with the rollover effect

[code:html]


<a href="http://www.domain.com" onMouseOver="handleOver();return true;" onMouseOut="handleOut();return true;"><img name="imgName" alt="Rollover!" src="/images/1.gif"/></a>

[/code]

The reason this method is used so commonly is because it is simple to implement and, more importantly, avoids the "lag" on the first mouseover that comes when using a CSS background-image switch on an selector:hover rule due to the delay required to download the rollover image. One thing that a lot of people don't realize is that there are methods to accomplish this effect in CSS without the initial rollover lag.

Method One - CSS Preloading

This is the quick and dirty way to force browsers to download rollover images when they initially load the page. Let's say you have the following document:

[code:html]


<html>
<head>
<title>My Rollover Page</title>
<style type="text/css">
#rollover{background:url(/images/1.gif);}
#rollover:hover{background:url(/images/2.gif);}
</style>
</head>
<body>
<div>
<a id="rollover" href="http://www.domain.com">My Rollover Link</a>
</div>
</body>
</html>

[/code]

In this page there would be a noticible delay when a user first mouses over the "rollover" anchor. The CSS Preloading method uses an invisible dummy element set to visibility:hidden, and has the "active" version of the rollover image set as its background.

[code:html]

<html>
<head>
<title>My Rollover Page</title>
<style type="text/css">
#preload{position:absolute;visibility:hidden;}
#image2{background:url(/images/2.gif);}
#rollover{background:url(/images/1.gif);}
#rollover:hover{background:url(/images/2.gif);}
</style>
</head>
<body>
<div id="preload">
<div id="image2"></div>
</div>
<div>
<a id="rollover" href="http://www.domain.com">My Rollover Link</a>
</div>
</body> 
</html>
 

[/code]

Method Two - Image Visibility Swap

This method accomplishes the same goal of forcing the browser to load both of the rollover images, but attacks it in a different way. Using the same example as above, we basically set the background of the containing anchor element to the "active" state of the rollover, and set the contained image to be the "inactive" state. Then it's just a matter of hiding the image element on hover.

[code:html]

<html>
<head>
<title>My Rollover Page</title>
<style type="text/css">
#rollover{background:url(/images/2.gif");display:block;height:50px;width:50px;}
#rollover:hover img{visibility:hidden;}
</style>
</head>
<body>
<div>
<a id="rollover" href="http://www.domain.com"><img src="/images/1.gif" alt="My Rollover's Inactive Image" /></a>
</div>
</body> 
</html>  

[/code]

This is the method that this site uses for the ColinCochrane.com logo in the header.

Method Three - Multistate Image

This method avoids the preloading problem altogether by using only one image that contains the inactive and active states. This is accomplished by creating an image that has the inactive and active versions stacked on top of eachother, like so:



Then all you do is set the element's height to half of that of the image and use the background-position property to shift the states on hover:

[code:html]

<html>
<head>
<title>My Rollover Page</title>
<style type="text/css">
#rollover{background:url(/images/multi.gif") bottom;display:block;height:20px;width:100px;}
#rollover:hover{background-position:top;}
</style>
</head>
<body>
<div>
<a id="rollover" href="http://www.domain.com"></a>
</div>
</body> 
</html>

[/code]


Now you have some different techniques to consider when implementing rollover effects on your website.