Re: Collapsing elements

On Thursday 21 February 2008 16:14, Daniel Glazman wrote:
> Bert Bos wrote:
> > A pseudo-class represents a state. According to CSS, elements can
> > be active, visited, link, first-child, disabled, target, invalid,
> > etc. I'm adding one more: initial.
> >
> > How do you currently query CSS states from Javascript? Can't you
> > generalize (one of) the existing methods to include ':initial' as
> > well?
> >
> > And there is actually nothing special about the LI. In my example
> > the LI *doesn't* have an ':initial' state. There may be any number
> > of elements whose states influence the style of the LI, because of
> > cascading or inheritance.
>
> Riiiiigggghht. But this does not solve my problem here. You can't
> query the :visited state from non-chrome JS for instance. Any
> CSS-based solution for foldable tree-like rendering of elements w/o a
> JS way to query the state is useless.

I wouldn't quite say it's useless... :-)

But if there is such a need to query the state of an element, what stops 
us from inventing a function and putting it in the CSSOM? Here is the 
first draft:

    isInitial: element → boolean ∪ ⊥

It gives one of three answers: true, false or nil. In an OOP language, 
the first argument would probably be written on the left side of the 
function name: "element.isInitial()".



Bert
-- 
  Bert Bos                                ( W 3 C ) http://www.w3.org/
  http://www.w3.org/people/bos                               W3C/ERCIM
  bert@w3.org                             2004 Rt des Lucioles / BP 93
  +33 (0)4 92 38 76 92            06902 Sophia Antipolis Cedex, France

Received on Thursday, 21 February 2008 19:09:22 UTC