- From: E. Stephen Mack <estephen@emf.net>
- Date: Sat, 26 Jul 1997 14:59:36 -0700
- To: www-style@w3.org
I am co-writing a book on HTML 4.0 that features a chapter on Style Sheets. I will be writing a few quick notes to www-style regarding some perceived inconsistencies in style sheet implementations for potential discussion. Hopefully my questions and examples will be of some interest to other www-style subscribers. Håkon, thanks very much for your quick response. At 10:19 PM 7/26/97 +0200, Håkon Lie <howcome@w3.org> wrote: > (minor point, the first colon should be omitted in the above example: > H1, H1, H3 { color: white; background: blue; } Thanks for the correction -- I noticed the typo after sending the mail, I'll try to double-check my examples more thoroughly in the future. I wrote: >> I'm also stunned by how wildly different a style sheet >> can be interpreted by Navigator 4.01, IE 3.02, and IE 4.0 platform >> preview 2 on my Windows 95 system. Håkon wrote: > This is indeed a concern and some people have proposed temporary > reliefs [1] until implementations are aligned. > [1] http://www.verso.com/agitprop/css/ Since the book that I'm co-writing is for newcomers to HTML, I will not be describing a script-based solution, as is presented on Todd Fahrner's interesting page. Instead, I will try to teach an introduction to the use of style sheets that considers current implementations so as to use "safe examples" as much as possible (while also presenting some of the dangerous examples). Even when implementations do become aligned, I am concerned that there will still be significant numbers of people using the old versions for quite some time. (Consider evidence that there are many surfers still using pre-2.0 betas of Navigator, for example.) For this reason, it's far better that a browser not implement styles AT ALL than to implement them incorrectly. To have browser versions in common use with broken interpretations of correct style sheet syntax is much more of a setback for a style sheet author than if the browser simply ignored style sheets. IE 3.x's style sheet implementation is the most dangerous, since so many of the test pages fail dramatically, as demonstrated by http://www.w3.org/pub/WWW/Style/css/msie/ For this reason, I predict that use of Todd's script (or variations on it) to disable style sheets for IE 3.x will become common. Håkon's test page at http://www.w3.org/Style/CSS/Test/ is a good confirmation of the problems with all of the current implementations. (Håkon, this page and the MSIE 3.0 test page don't seem to be linked from the rest of the CSS pages, and the only reason I found out about them was from reading the back issues of www-style. I think these pages are enormously useful for people learning about style sheets, so you may wish to consider adding a link to http://www.w3.org/Style/CSS/ that leads to http://www.w3.org/Style/CSS/Test/ if possible.) Given the three popular platforms that support style sheets, there are serious gaps in their basic support of the feature of style sheets, let alone the style sheet implementation itself. * IE 3.x and Navigator 4.01 both allow a user to disable author style sheets, but don't offer a method of supplying any user- defined style sheets to substitute or supplement author-defined style sheets. * IE 4.0 platform preview 2 allows you to supply a user-defined style sheet, but doesn't offer a process of disabling author style sheets (except for colors, font styles and font sizes). All three of these browsers suffer from implementations of style sheets that are flawed in numerous ways, as is well known to readers of this list. Netscape acknowledges some known issues at http://developer.netscape.com/support/bugs/known/css.html but there is no similar list from Microsoft that I'm aware of. I've seen the five resources demonstrating current implementations that are listed at http://www.w3.org/pub/WWW/Style/css/#browsers Today and tomorrow I will post some examples and screen shots for discussion of implementations, in part to determine which browser is correct. -- E. Stephen Mack <estephen@emf.net> http://www.emf.net/~estephen/
Received on Saturday, 26 July 1997 17:58:36 UTC