Re: CSS3 Values and Units: Some proposals

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From: "Markus Ernst" <derernst@gmx.ch>
Sent: Wednesday, March 17, 2010 4:02 PM
To: <www-style@w3.org>
Subject: CSS3 Values and Units: Some proposals

> I am new to www-style; I spent quite some hours searching the list 
> archives - if these topics might have been discussed before, I apologize. 
> (BTW, another Newbie question, is there any information available about 
> when this more than 3 years old draft will proceed to the recommendation 
> stadium?)
>
> Looking through the CSS3 Values and Units draft, I found some things 
> missing that I think would make meveryday work for me as an author easier:
>
>
> 1. Units that cover the maximum viewable or scrollable space
>
> There are the vw, vh and vm units in the draft. However, they do not solve 
> problems such as backgrounds that are not continued when scrolling is 
> necessary.
>
> I suggest to add 2 more units, they might be named "page width" and "page 
> height":
> - pw: the viewport's width or maximum contents width, whichever is greater
> - ph: the viewport's height or maximum contents height, whichever is 
> greater
>
> Use case: A navigation column with a background. If the contents extend 
> the viewport, the background of the navigation column is supposed to be 
> continued to the bottom of the page - just the same behaviour as in a 
> HTML3 table layout with <table height="100%">.
>

If some element inside the document will have width:1.2pw; what would be its 
computed value?
It appears that this will create indefinite recursive calculation loop.

>
> 2. A method to adjust the dimensions of elements
>
> I suggest to introduce a method to give some elements the same width or 
> height, without knowing the appropriate value. This could be achieved by a 
> function that looks for the computed dimensions of all elements covered by 
> a selector, and gets the highest one.
>
> Use cases:
> - Align labels and fields in a form without a table.
> - Adjust several elements with position:absolute to each other, for 
> example to achieve a multi-column layout
>
> For a part of a simple form:
> <p><label class="aligned">Age:</label><input type="text"></p>
> <p><label class="aligned">Preferred tea:</label><input type="text"></p>
>
> .... the CSS could look like this:
> label.aligned {
>  width:max(width, .aligned);
> }
>
> The function max() takes 2 arguments:
> - the dimension to be looked for
> - the selector that covers the group of elements whose dimension is looked 
> for
>

The same problem as above - recursive calculations.

>
> 3. A unit computed against "the rest of the space"
>
> This is meant similar to the star * in framesets. I admit I am astonished 
> not to find this in the draft.
>
> Use case: Proportional, but not centered placement of an element. Example:
>
> div#container {
>  width:50em;
>  margin-left:2*;
>  margin-right:1*;
> }

You are not alone who astonished.

Take a look on this proposal:
http://lists.w3.org/Archives/Public/www-style/2009Apr/0154.html
in particular: 
http://www.terrainformatica.com/w3/flex-layout/flex-layout.htm
I believe it is precisely what you want.

-- 
Andrew Fedoniouk.

http://terrainformatica.com

Received on Thursday, 18 March 2010 04:00:16 UTC