JavaScript Archives - Page 7 of 8

WCAG Samurai Errata now finalized

The WCAG Samurai Errata published a final version of their suggested improvements. This is the work of a group of independent accessibility experts formed by Joe Clark to attempt to address shortcomings in the WCAG, a W3C recommendation from 1999. From the Introduction:

The first thing to understand is that you do not have to comply with these errata. The WCAG Samurai errata are an optional addition to WCAG 1, which we use as a base. You start by reading and understanding WCAG 1, then you read these errata as a correction to WCAG 1.

Read the Introduction for an overview and summary of the main points. Then you can get into the details. A few highlights of the recommendations by the Samurai are that you must comply with all Priority 1 and 2 guidelines, but you must not attempt to comply with Priority 3 guidelines. Layout tables, frames, and untagged PDF documents are banned. Video soundtracks must be captioned. Sites must use valid code and correct semantics for content.

There are separate documents for color and PDF.

If you do choose to comply with these guidelines, there is suggested phrasing for inclusion on your website. An example: “Our site is built to comply with WCAG+Samurai.” There is no mention of which tools are capable of making an evaluation such as this.

I’d like to see a standards advocacy group like the Web Standards Project or a Samurai-like group take on one more thing that is a constant concern to me. I use ads and other third party content on my site from sites like Amazon, Google, Flickr, and Yahoo. These third party sources do not provide valid HTML. Pressure on vendors to provide valid HTML would be an important project to improve the web. I know this wasn’t the aim of the WCAG Samurai, I’m just saying . . .

The Need for Speed: Externalize your JavaScripts and CSS

Let’s say you have an HTML page that weighs in at 8K. You have some CSS that might contain 32K. And you have a couple of JavaScripts that are 4K and 12K. That adds up to 56K.

If you put the CSS and the JavaScript information in the HTML, you still have 56K. One would assume 56K is 56K no matter what. However, there’s a little thing known as browser cache to take into account.

Let’s say every page in your site uses the CSS and JavaScripts we’re talking about. If those are externalized, then the very first time a page from your site is downloaded, all 56K gets downloaded. But the external CSS and JavaScript files get cached. Which means, for all subsequent pages that are downloaded, all the browser sends out a request for is the HTML. If the HTML is all content (no presentation, no scripting), speed rules.

Review: Head First JavaScript

January 31, 2008 by

Virginia DeBolt
product

Head First JavaScript

★★★★★ Head First JavaScript by Michael Morrison (O’Reilly, 2008) may not ring up five stars for everyone, but I like the Head First books. They appeal to the educator in me, the person who understands multiple intelligences and learning theory. The educator in me knows why these books work for a lot of people who can’t make sense out of a “normal” programming language manual.

The Head First books are not your average technical manual. They are full of redundancy, humor, images, practice exercises, goofy conversations between things like global and local variables and dumb questions.

I have to give this book credit for my first ever spontaneous JavaScript insight. After reading about one of the simpler JavaScript functions, I actually thought, “Oh, that’s how the Dreamweaver CSS dialog works.” Now, I’m not the sort of person who thinks in terms of JavaScript. I think in HTML. JavaScript has been something I do carefully and by slavishly copying someone else’s direction. So I must attribute my spontaneous JavaScript insight to the fact that the type of learning experience you get from a Head First book works in my brain.

Here’s what the chapters in the book discuss:

the interactive web
storing data
exploring the client
decision making
looping
functions
forms and validation
wrangling the page
bringing data to life
creating custom objects
kill bugs dead
dynamic data

If you’ve tried other JavaScript books and couldn’t get much out of them, try this Head First book. Recommended.

Technorati Tags: book review, Head First JavaScript

Some useful links

The seven rules of unobtrusive JavaScript, by Christian Heilmann, gives reasons for the rules and code examples to explain.

Some Job Hunting Advice from Simple and Loveable has good suggestions for students just ready to graduate as well as experienced web designers looking for a new job.

MacWorld reports on a study by Nemertes Research Group that says that the increase in video and other Web content could overwhelm the Internet by 2010 unless backbone providers invest up to US$137 billion in new capacity, more than double what service providers plan to invest.

World Changing reports on news that eating chocolate can help save the world.

Review: Accelerated DOM Scripting with Ajax, APIs, and Libraries

Reviewer: Virginia DeBolt

Summary: very useful

product

Accelerated DOM Scripting with Ajax, APIs, and Libraries (Pro)

Rating: 5/5

Accelerated DOM Scriptiing with Ajax, APIs, and Libraries is from Apress (2007). The book is mainly by Jonathan Snook, with additional chapters from Aaron Gustafson, Stuart Langridge and Dan Webb. Each of the additional chapters provides an example case demonstrating the techniques described by Snook throughout the book.

Snook is an excellent writer. Economical with words (this is a small book), but absolutely clear and easy to understand. Programming is not my subject. So much of this book was beyond my expertise. However, there were many parts of the book that do fall within my expertise, and I was highly impressed with the explanation, clarity, and philosophy behind the ideas that Snook included.

Chapters included JavaScript, HTML, CSS, and object-oriented programming. These were not basic level material, but were high-level explanations as to how these technologies work together in Ajax and JavaScript. The chapter on libraries listed the best choices. The chapter on visual effects talked about building animation objects. The three demonstration chapters covered form validation, a FAQ facelift, and a dynamic help system.

Presentation: Ten Checkpoints of a Web Standards Based Curriculum

I presented this at HighEdWebDev 2007 today. It was presented as a powerpoint presentation. My narrative explained that this presentation was mainly about what sort of student learning outcomes I would expect to see in an institution where web standards were part of the curriculum. I did touch on a couple of important overall considerations as well.

I have captured only the slides and converted them into a movie. There is no sound. Please return to this post if you have comments or questions.

View the movie.

Technorati Tags: web design, accessibility, usability, CSS, web design education, web standards, HighEdWebDev2007

Yahoo! UI Library (YUI)

A tip of the hat to Dori Smith for pointing out the Yahoo! UI Library (YUI): “The Yahoo! User Interface (YUI) Library is a set of utilities and controls, written in JavaScript, for building richly interactive web applications using techniques such as DOM scripting, DHTML and AJAX. The YUI Library also includes several core CSS resources. All components in the YUI Library have been released as open source under a BSD license and are free for all uses.”

Plenty of resources to help you with the YUI components such as a blog, a forum, documentation. Good stuff.