Don't call me DOM » Mobile Web

W3C Cheatsheet for developers

Dom — Thu, 05 Nov 2009 22:00:46 +0000

I’ve been working over the past few weeks on a nifty little tool that summarizes a number of W3C technologies, including the Mobile Web Best Practices, in a mobile-friendly format, called the W3C Cheatsheet.

See my post in the W3C blog to learn more about it, and send your feedback!

Device APIs on the way

Dom — Fri, 16 Oct 2009 14:40:57 +0000

Validating XHTML Basic 1.1

Dom — Tue, 16 Jun 2009 16:03:23 +0000

As I was trying to validate a large number of XHTML MP 1.2 files (the ones in one of the OMA’s XHTML MP test suite – whose welcome page itself ironically is not well-formed), I realized that the tool I was using, based on the WDG HTML validator as packaged by Debian, was making network access requests when used on these XHTML MP 1.2 files. I then moved to use xmllint with the --valid option, but it had the same behavior.

As one of the W3C Systems team member, I’m acutely aware how bad is the practice of fetching DTDs over the network over and over again.

Furthermore, the OMA XHTML MP 1.2 DTDs are broken – they include non-UTF-8 characters in the comments of one of the modules (bug that I have reported a while ago but that still hasn’t been fixed apparently).

But given that XHTML MP 1.2 is mostly equivalent to XHTML Basic 1.1, I thought I would validate the said files against that DTD – but I wanted to make sure I wouldn’t hit the network when doing so.

Unfortunately, the XHTML Basic 1.1 DTD was not installed in my local XML catalog by default as part of the others DTD in the w3c-dtd-xhtml package – I’ve filed a bug report in the hope that it will be in the future, along with the XHMTL+RDFa DTD.

So I looked into adding the XHTML Basic 1.1 DTD to my local XML catalog, and marking it as an equivalent of the XHTML MP 1.2 DTD at the same time. Given that this wasn’t exactly straightforward, I thought I would document here what I did to set that up on my Ubuntu Jaunty install, in the event that someone else would need to do something simiar:

first, I added the following lines to my /etc/xml/catalog file:
I edited /etc/xml/w3c-dtd-xhtml.xml to add the following lines:
I created the directory /usr/share/xml/xhtml/schema/dtd/basic11/ and put the following files in it (available as a Zip file):
- the SGML Catalog definition of XHTML Basic 1.1 – since I’m now using xmllint rather than the WDG validator, I’m not sure if it works or is useful as is
- a modified XML Catalog file that points both the XHTML Basic 1.1 FPI (-//W3C//DTD XHTML Basic 1.1//EN) and the XHMTL MP 1.2 FPI (-//OMA//DTD XHTML Mobile 1.2//EN) to the XHTML Basic 1.1 DTD
- a corrected version of the flat DTD for XHTML Basic 1.1, that includes all the necessary modules as a single file – while it was based on an old version developed by the XHTML Working Group, I had to update it quite a bit to make it actually represent what the XHTML Basic 1.1 spec says
- I have also included other files that I had found in the similar catalog directory for XHTML Basic 1.0, but I think they’re only useful for SGML-based validation, rather than XML-based – they are also in the Zip file, but may not be useful
With these changes, I’m now able to validate my XHTML MP/Basic files without hitting the network. But the main lesson for me remains that it isn’t exactly trivial to add DTDs to a catalog when it isn’t done by people who actually know what they’re doing…

Proposed new group to work on Device APIs

Dom — Mon, 01 Jun 2009 08:53:55 +0000

Last week, W3C started the formal process to start a new Working Group that would focus on the development of client-side APIs that enable the development of Web Applications and Web Widgets that interact with devices services such as Calendar, Contacts, Camera, etc.

If the group's creation is approved, this means that in a year or two, Web developers should have a bunch of new standard APIs to make their Web applications even more compelling and integrated with their hosting platforms; on mobile devices, this would make the Web platform an even stiffer competitor to the existing development platforms.

Stay tuned - we should know more about whether this group will go ahead in a few weeks.

XHTML Basic 1.1 Proposed Edited Recommendation

Dom — Thu, 07 May 2009 15:43:43 +0000

Mobile at WWW2009

Dom — Tue, 28 Apr 2009 14:17:24 +0000

Device Independent or Accessible? at European Accessibility Forum

Dom — Tue, 31 Mar 2009 15:34:41 +0000

Exploring the world of Web video

Dom — Wed, 11 Feb 2009 14:33:20 +0000

A colleague of mine recently pointed me to Michael Wesch’s great and inspiring anthropological introduction to YouTube, which made me curious about the use of video as an expression mechanism on the Web.

Coupling this with my recent upgrade in the camcorder world to a fully digital device, and the early results of the Video in the Web activity W3C started a year ago, I had to start playing in this area to understand it better.

As a starting point, I thought that I would use the video of the presentation I made to ParisWeb back in 2007 on the Mobile Web Best Practices, also available un-flashed on ParisWeb servers – usefully made available in a by-nc-sa Creative Commons license.

One thing that I needed to take into account, but was also a driver for this exploratory work, is that we are about to adopt a W3C internal policy that we can only publish media on-line if we ensure a minimum level of accessibility – at this time, this minimum level requires providing a full transcript of any material.

This post serves as an introduction to my adventures in the hazardous world of Web videos, where you’ll find me finding my way:

in the world of transcription, and the tools available to that end on linux,
in the formats for publishing and associating the transcripts with the video,
the proposed HTMLMediaElement DOM Interface to make it possible to synchronize events with media playing, adding a pinch of JQuery, RDFa and Media Fragment to taste.

At the end of these stories, you will join me in rejoicing in front of a synchronized, close-captioned and annotated video and slides presentations viewer for your browser – if you browser lives sufficiently on the edge, that is (which I think at this time means specifically Firefox 3.1 beta), and if you’re patient enough to deal with video operations on a 85 MB video. And if you speak or read French.

And if you’re not patient enough to go past these obstacles, I have prepared a screencast of the system in action:

Transcript:

[the screen shows a Web page in a browser, split in 4 zones]

This is a screencast of a presentation viewer written in HTML and Javascript.

You can see here [on the top left corner] the area where the video will appear, here [on the top right corner] the slides that will accompany the video presentation, and there [on the bottom left corner] a table of contents.

If I start the video here [clicking on the play control of the video], you can see the closed captions appearing below the video.

And then I can navigate in the video and the presentation using the table of content.

And you can see how the video and the slides get updated live, and I can even have side notes appearing on the side [bottom right corner] of the screen.

(also available as Ogg/Theora video with a Timed Text transcript.)

Social Networking Workshop Report

Tue, 03 Feb 2009 15:50:48 +0000

Return of the Mobile Style Sheet in A List Apart

Tue, 06 Jan 2009 13:23:24 +0000

An article I wrote on the use of style sheets targetting mobile devices, titled Return of the Mobile Style Sheet, is published today in A List Apart.

It gives some practical advices on how to combine CSS Media Types, CSS Media Queries with a bit of tooling help from Javascript and server-side filtering, to create a mobile-friendly CSS layout that will work across a large number of devices.

Return of the Mobile Style Sheet in A List Apart

Tue, 06 Jan 2009 13:23:24 +0000

Published in A List Apart

Dom — Tue, 06 Jan 2009 12:32:25 +0000

A List Apart just published an article I wrote, Return of the Mobile Style Sheet, that focuses on how to write and deploy CSS style sheets specifically targeted at mobile devices, even on devices that don’t use the handheld CSS Media Type. Woohoo!

That article was very much inspired by the work the Mobile Web Initiative Team did for its site redesign, as well as W3C’s still ongoing work on a whole redesign of the W3C site.

But more importantly, I took some of the most useful statistics from the data gathered by the Mobile Test Harness: thanks to all the contributors!

Particular thanks to Ian Jacobs and François Daoust who provided lots of useful feedback and edits, and the ALA team who also helped polish the article quite a bit!

2008 mobile web standards fireworks

Mon, 05 Jan 2009 14:46:19 +0000

Dan Appelquist on W3C Q&A Blog

Tue, 25 Nov 2008 08:13:56 +0000

Extended deadline to submit position papers to workshop on the Future of Social Netorking

Thu, 20 Nov 2008 12:25:42 +0000