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Bruce Lawson submits the review below of Stuart Langridge's Excellent guide to creating dynamic web pages; scalable and sensible., writing "Don't be put off by the title: the DHTML here bears no resemblance to the stupid Web tricks of the late 90s that allowed animated unicorns to follow your cursor or silly Powerpoint-like transitions between Web pages." Read on for the rest. DHTML Utopia: Modern web design using JavaScript and DOM author Stuart Langridge pages 300 publisher Sitepoint rating 8 reviewer Bruce Lawson ISBN 0957921896 summary Excellent guide to creating dynamic web pages; scalable and sensible.

This book is the opening salvo in the latest battle in the Web Standards war -- the battle for unobtrusive JavaScripting, or Unobtrusive DOMscripting as many call it, in order to rid it of all the negative connotations that "DHTML" and "JavaScript" bring. Combined with the non-standard XMLHttpRequest object, it's sometimes referred to as "Ajax". Terminology aside, though, what are the substantive differences between the old-skool and the "modern" of the title?

• Graceful degradation. A great example of this is Google Suggest in which the DOMscripting enhances functionality by making the page feel more responsive, but if you don't have JavaScript for some reason, the page still works.
• Separation of structure, presentation and behaviour. The DOMscript deals with the behaviour in the same way as CSS defines the presentation in the brave new Web standards world, and the three remain separate. The html has no JavaScript in it at all -- everything is handled by in separate code files.
• No browser sniffing. This aims to future-proof code by testing for features rather than sniffing for browser name and version. So, before using the TimeTravelCureCancer method, the current browser is tested to see whether it's supported. If it is, the script continues. If it isn't,the script silently fails with graceful degradation.

Theory sounds cool -- how's the damn book? I was pleasantly surprised by how quickly the book gets to work. Even before page numbering begins, the introduction has a lucid and compelling argument for using HTML 4.01 rather than XHTML as the markup language of choice.

Chapter 1 has a brief (6-page) overview of the importance of valid code and separating presentation into CSS, and a short description of the unobtrusive nature of Langridge's scripts: no script in the mark-up at all; instead, the .js files contain "event listeners." The reasons why this is desirable are promised later. Chapter 2-4: The basics Now that document.write in the html is no longer needed, you need to know the "proper" way to add text or elements to a Web document. So Langridge gives us a tour of the DOM, showing how to walk the DOM tree and create, remove and add elements to the tree. It's methodical, and by the time I was beginning to get a bit tired of theory and thinking that you'll have to prise document.write out of my cold, dead hands, we get an "Expanding form" which allows us to expand a form ad infinitum to sign up as many friends as you want to receive free beer, without ever going back to the server. (You can see such a thing in action in gmail, when you want to attach multiple documents to an email).

I started to warm to the author and his style. 33 pages into the book, and we get a real-world working example to examine (I like my theory liberally garnished with practice). I also feel a kinship with authors who fantasise about mad millionaire philanthropists giving away beer.

By chapter 3, we've really got going. Apart from one rather pedantic edict (the event is mouseover, the event handler is onmouseover and we should separate the nomenclature, even though it makes no practical difference), the focus here is on real-life browsers. And, as we all know, in Web dev books, real-life browsers means grotesque exceptions to our ideal-world rules .Strangely -- and oddly satisfyingly to this PC user -- the culprit isn't only the perennially despised IE/ Win; shiny Safari comes in for a good bit of stick!

The real-world example here is a data table that highlights the whole row and column of any cell that's being moused-over. Now, in any modern browser except for IE/ Win, the row could be given a hover pseudoclass (IE/ Win only allows :hover on anchors). But as there is (weirdly) no HTML construct for a column, this effect can only be achieved through DOMscripting. What the script does is to dynamically append a class name to every cell in the row and column at run time -- and the pre-defined CSS file determines the styling of that class.

Herein lies an advantage in Unobtrusive DOMscripting: you could just take this script and plug it into a Web site without changing any of the html (except to add a link to the script file in the head). But the script is relatively complex for a newbie to code, and for the techniques to be widely used, I suspect that the billion old-skool cut'n'paste JavaScript sites will need to be replaced with a single, canonical library of modern scripts for people to cut and paste from. For those who find CSS challenging, JavaScript is probably even more complex. . Chapters 5 - 7: blurring the division between Web UI and application UI It's a truism that the Web has set back UI development some years -- in fact, back to the old dumb-terminal paradigm of filling in a screen full of data, pressing the button to send it back to the mainframe and waiting for the next page to be sent -- or the old one returned with errors noted.

Langridge shows that we can make the experience smarter than this, going beyond the traditional JavaScript client-side validation interactivity by adding animation to allow text to fade in and out over time, styling tooltips to be sexier than the default yellow box and which can gently appear into view rather than the browser default on/ off state are examples that struck me.

When I first read these, I thought they were cheesy gimmicks -- the modern equivalent cursor-following unicorn -- until I considered more deeply and realised that many of the UI elements that we enjoy in modern desktop apps are precisely these small, cosmetic effects: abrupt transitions, lack of transparency, sharp edges to UI widgets all feel like old operating systems or clunky Web pages.

It's not all touchy-feely; we get auto-complete text entry, degradable calendar pop-ups, flyout menus and lessons in OOP, encapsulating code for re-usability, and avoiding Internet Explorer memory leaks. Chapters 8- 10: seamlessly working with the Server So far, so client-side. Where Unobtrusive DOMscripting really gets developers juices flowing is the ability to communicate with the server without obviously refreshing the page. Chapter 8 takes you through a variety of methods. Some, like the hacky iframe method or hideous 204 piggyback method are so gruesome that I breathed a sigh of relief loud enough to wake the cat when I finally turned the page to read "XMLHTTP". This method (which is non-standard and introduced by Microsoft) has ushered in the Next Great Web Thing: asynchronous communication with the server. Langridge walks through using the Sarissa library to make a user registration form that checks whether the user name you choose is taken, and if so, suggest some alternatives without refreshing the page.

There's a lot of unresolved accessibility problems with the Ajax method (how does a screenreader alert the listener to the fact that something new has appeared on the page? How do they navigate and hear the new stuff in context?) and while it is laudable that Langridge notes these issues exists, I'd hoped he would have suggested some solutions. He doesn't, but as he's a member of the Web Standards Project's DOMscripting task force I'm guessing it's being worked on.

The project that really kicks ass in this section is a file manager, like the one in most people's Web site control panels, where you can actually drag and drop the icons, like an operating system, and the server does the work. Langridge carefully goes through all of the steps, all of the pitfalls and all of the code needed to make this happen in any modern browser.

It doesn't take a lot of imagination to realise just how this could revolutionise the Web experience. Drag and drop products into a shopping cart. Drag the shopping cart to the checkout icon. Moving money around bank accounts in some integrated internet banking application. The possibilities are huge. Conclusion The whole technique of unobtrusive DOMscripting needs further research before it's ready for prime time -- particularly from an accessibility point of view, but then as an accessibility bore you'd expect me to say that. I think it's beyond question that there's ideas in here that radically enhance the usability of Web-based applications by making them more intuitive and more like the desktop drag-and-drop interface we know from our desktops.

This is a good-humoured, thoroughly-researched book that combines theory with practical learn-by-doing examples. To this reviewer, the code appears scalable and sensible. This book is never going to appeal to the quivering aesthete designers -- probably because it's fundamentally about code. But precisely because it proposes a complete separation of code and design, it facilitates the advancement of the Web.

You can purchase DHTML Utopia: Modern web design using JavaScript and DOM from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.

Bruce Lawson writes "I've read a lot of CSS books, but this one is the one I wished that I'd read when I was learning, and I suspect that other slashdotters may concur. It is firmly pitched at the coder rather than the designer, takes you from CSS virgin to upper intermediate level, with good attention to the process of (re)designing with CSS, legal issues such as Accessibility (section 508), and assumes that you're not scared of mark-up." Lawson offers this disclosure: "I should immediately disclose that I've worked for two different companies that have published the author, Rachel Andrew, but I have no connection with the publishers, or this book." Read on for the rest of his review. The CSS Anthology: 101 Essential Tips, Tricks & Hacks author Rachel Andrew pages 380 publisher SitePoint rating 8 reviewer Bruce Lawson ISBN 0957921888 summary Structured Q&A guide for CSS beginners

Author's credentials

Andrew is a long-term member of the Web Standards Project (WaSP) and programmer, technical project manager, technical team leader/senior developer and webmaster, according to her own bio.

Who's the book for?

The book's subtitle is somewhat misleading. There probably are 101 tips'n'tricks (I didn't count) but it's not the random miscellany that it implies. The information is structured so that a n00b could become proficient by reading the book from start to finish (I tested this out on a colleague). The tips'n'tricks structure does allow you to find what you're looking for in a hurry. The table of contents is easily scanned, and there is an excellent index.

The book doesn't offer advice on how to sex up the beauty of your site. That's fine for me; my current work involves replicating someone else's designs using xhtml and CSS, and as a coder I'm pathologically unable to design the type of showcases that you see at the CSS Zen Garden. A graphic designer might therefore find this book hard work; it jumps straight into a discussion of syntax, and there's occasional geek-directed statements (CSS supports multi-line C-style comments). Similarly, if you're completely new to html, this book probably isn't for you; there's lots of references to pre-CSS ways of working which could potentially be mystifying. Unusually for CSS books, there's a refreshing lack of polemic telling you why you should use style-sheets. If I read another history of the browser wars in a technical book, I shall scream.

So the book's constituency would seem to be those who know how to present information via html, and wish to take advantage of the smaller filesizes, greater flexibility and logical separation of the presentation layer from the mark-up that the (x)html/ CSS combination offers. The logical purity is my personal reason for moving to Web Standards; the trauma of writing text processing applications with VAX Fortran in the late '80s left me with the propensity to weep when I see html as sorely abused I mangled dear old Fortran.

Are you sitting comfortably? Then I'll begin.

Anthology kicks off in the conventional way for CSS books - controlling fonts and colours, styling hyperlinks, headings and the like. Each chunk is structured as a problem (How do I remove the indented left margin from a list?), a solution and sample code, and generally a discussion of related applications of the code, compatibility issues, accessibility notes etc. This is a pretty compact method of explication, and the basics of styling, syntax, pseudo-class order and the like are romped through in 40 pages, but not glossed over. The key to this is that Anthology assumes you know what you want to do, and shows you how to do it.

Chapter 4 (Navigation) is where the real meat begins - making navigation menus that are solely html unordered lists (because a menu is logically a list of links) and styling with CSS, adding rollover effects, styling navigation as buttons, changing the styling to a horizontal navbar, or even Amazon-style tabs without changing the mark-up. I suspect that, although these are techniques that can be found in most CSS books, the brevity and simplicity of the explanation will be revelatory to many. Chapter 5 (Tabular Data) may come as a surprise to those who mistakenly believe that web standards disallows the use of html tables, as it shows how to style tabular data - the examples are a spreadsheet and a calendar. Chapter 6 repeats the trick with that most mundane aspect of web development, the form.

Chapter 7 (Browser and Device Support) is about real-world CSS development. Unlike most books which instruct you to test in loads of browsers and leave it at that, this chapter lists all the main permutations of OS and browser (including tips on installing multiple versions of IE/ Win), and begins discussion of the tried and tested hacks to hide styles from Netscape 4, IE etc. All of this information is available on the web -- but for a newbie who isn't yet aware that it's possible to hide styles from certain browsers, it's a great way to introduce them to the murky practices of real-world CSS development. What's also refreshing in a computer book for n00bs is a discussion of how to seek help on lists and forums, with a guide to etiquette.

Chapter 8 (CSS Positioning and Layout) is where the stuff that stumps many a table-based designer begins. Along with fonts and colours etc, CSS can lay out the stuff on your page. I'm unsure about the success of this chapter; the Q&A structure is great if you're looking to build one of the sites that are explained (and the list is pretty comprehensive), but I came to the chapter hoping to cure a couple of bugs I'd found in a project I'd previously semi-successfully laid out with absolute positioning (A.P.).

Generally, I layout using floats as I also write the html, so it's easy to ensure that the markup spits out <div>s (sections) in the left-to-right, top-to-bottom order that I want to lay them out in. Suddenly, I had two projects that required A.P. for the first time, as it was not cost-effective to change the way that the client's CMS spat out the markup, so AP was required to position sections on the page regardless of where they appeared in the markup.

Anthology served me fine until I tested the page in IE and the layout was off. Nothing in the book gave me any pointers, and in the end I gave up Googling and just used a hack which exploits an IE parser bug to serve different co-ordinates to IE, after finding the hack co-ordinates through trial and error:

#APthing {position:absolute; top:34px; left: 758px; width:108px; height:88px;}
* html #APthing {position:absolute; top:19px; left: 785px;} /*for IE */

OK, so there may be a simple mistake I'm making -- but then, as far as absolute positioning goes, I'm the kind of newbie at whom this book is aimed, and I imagine that others will make the same mistake that I did. If the book had explained where I was going wrong, or given me the above hack, I'd've spent less time with Google and more time with Guinness.

Chapter 9 (Experimentation, Browser Specific CSS and Future Techniques) is successful, except for one small gripe. I'm glad that the author, although a member of the Web Standards Project, isn't an uber-purist. (I'm of the opinion that a little invalid code, if it's the only way to get the job done, isn't a hanging offense). So she shows how to implement IE-only proprietary CSS that can make colourful scrollbars, should you wish to do this. There's also a Mozilla-only CSS trick to allow curved edges to CSS boxes, which I implemented on my homepage that very evening.

However (here's the gripe), the most useful technique shown is one which allows fully-CSS flyout menus that don't rely on JavaScript. The author notes that it won't work for most people, as IE incorrectly restricts the hover pseudo-class to <a> tags only, while the CSS requires hovering over <li> elements.

Well, Yes and No. There's a well-documented and elegant hack which allows a proprietary Microsoft behaviour to be attached to the CSS that attaches a small JScript that corrects the IE bug, and thus allows this extremely useful CSS-only flyout menu to work in IE. I've used the technique myself when required to mimic the look and feel of a client's site while making it DDA/ADA accessible, and it works perfectly. To me, the omission of the IE hack from Anthology is an unfortunate oversight.

Summary

There's a couple of flaws in the book, though I suspect that in order to explain them, I've over-emphasised them. All in all, it's a solid, professional no-B.S. way for someone with a code-oriented mind to get them up to speed, satisfactorily and quickly; a motivated reader could be churning out standards-compliant, bandwidth-friendly sites after a few hour's experimentation. Ordering the book from the publisher's website was a good experience and, unusually, they have a money-back guarantee. As I said, I wish that I'd had access to Anthology when I was learning.

You can purchase The CSS Anthology: 101 Essential Tips, Tricks & Hacks from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.