[whatwg] Comments on <dialog>

[Brian Blakely]

On Fri, Jan 31, 2014 at 7:31 PM, Ian Hickson <ian at hixie.ch> wrote:

> On Wed, 18 Dec 2013, Brian Blakely wrote:
> > On Wed, Dec 18, 2013 at 2:13 PM, Ian Hickson <ian at hixie.ch> wrote:
> > > On Wed, 18 Dec 2013, Brian Blakely wrote:
> > > > On Tue, Dec 17, 2013 at 3:14 PM, Ian Hickson <ian at hixie.ch> wrote:
> > > > >
> > > > > I've added a rule to the spec that says that viewports have to be
> > > > > pannable so you can see all of a dialog, but I don't know how
> > > > > feasible that really is.
> > > >
> > > > I could see implementations using shadow <div>s to satisfy this It
> > > > might be beneficial to even codify kind of element as ::modal,
> > > > representing a modal layer acting as an ancestor for both the
> > > > ::backdrop and <dialog>.
> > >
> > > Not really sure how this would work. Can you elaborate?
> >
> > This is what the shadow DOM would look like for modal dialogs:
> >
> > ::modal
> > -  ::backdrop
> > -  <dialog>
> >
> > ::modal is <dialog>'s ancestor, and is available when showModal is
> > called. This allows authors to set CSS overflow to whichever value suits
> > their use-case, and for user agents to establish overflow: auto as the
> > default, making the dialog inherently pannable when it exceeds the
> > viewport.
>
> That seem somewhat novel, from the CSS perspective. I'll have to defer to
> implementors as to how feasible something like that is. So far, the
> feedback doesn't seem positive:
>

::modal is essentially a named alias for ::outside (
http://www.w3.org/TR/css3-content/#wrapping), which, sadly, has not been
implemented anywhere and hasn't seen public movement in quite a long while.