W3C home > Mailing lists > Public > www-validator@w3.org > August 2004

Re: [VE][131] Error Message Feedback

From: Tim Jackson <lists@timj.co.uk>
Date: Tue, 3 Aug 2004 09:35:39 +0100
To: "Jason Delaplain" <delaplain@hotmail.com>
Cc: <www-validator@w3.org>
Message-ID: <E1Bruln-0007YB-Qb@virt1.clust1.firecluster.net>

Hi Jason, on Tue, 3 Aug 2004 00:02:53 -0700 you wrote:

> There are a few invalid markups that I don't understand.  For instance,
> I had one that said ALIGN="ABSMIDDLE" should be "MIDDLE" instead.  When
> I adjusted it, it didn't show the image in the Absolute Middle.

Well, make sure you understand the distinction between what a standard
(well, a DTD anyway) says is valid, and what a user agent (a browser) does
with it.  Just because some browser interprets "align='absmiddle'" doesn't
make it a standard, and just because a standard says that you should use
"align='middle'" doesn't necessarily mean that browsers support it, or do
something useful with it. What you're talking about in terms of
"absmiddle" is, IIRC, an ugly proprietary hack introduced quite a long
time ago.

In this case, you might want to consider using CSS. Generally speaking,
the "vertical-align" property usually works reasonably well with modern
browers, although whether it gives you the pixel-perfection you're after
I'm not sure. Eric Meyer's book "Cascading Style Sheets 2.0 Programmers
Reference" has a very handy and succinct explanation of text alignment and
how it works.

> The other is a required ALT tag.  I don't see why an ALT tag is
> considered required.

Try looking at your site with images turned off (Opera is useful for this
as you can easily toggle on/off), or in a text-only browser (e.g. lynx or
links). Then you'll see. The ALT attribute is crucial to let a user agent
know what to display if it can't show images, including nothing. (If you
have images which are purely decorative and have no actual
meaningful content, set alt="" and then the browser will know that it can
skip over them.)


Tim
Received on Tuesday, 3 August 2004 04:35:41 UTC

This archive was generated by hypermail 2.3.1 : Wednesday, 5 February 2014 07:14:08 UTC