Re: Popup windows & style sheets

 From: Bert Bos <Bert.Bos@sophia.inria.fr>
| - if the pop-up contains a hyperlink and the user selects it, where
|   should the result go?
Should be specifiable (display-in: main-window | same-window |
new-window) as property of the anchor.
| - do we want to specify how long the pop-up stays on screen? until the
|   mouse is released? but then you can't click in it any more.
Should be specifiable (popup-duration: persistent | while-held |
| - if rendering becomes dependent on events (such as mouse clicks), you
|   enter the realm of scripting, which is a very different field and
|   full of mines.
I would agree, but I think the while-held model is a reasonable exception.
| - if the pop-up has a more permanent character, like a new window,
|   then you get into user-interface problems: in principle, no new
|   windows should appear, unless explicitly opened by the
|   user. Otherwise he might not know how to get rid of them again.
Definitely should support persistent windows; the author and/or user
should be allowed to make that decision (as opposed to the stylesheet WG
saying the decision is too dangerous to be allowed).  Clicking on a
sidebar or footnote link *is* an explicit user action.
| - we want not only linked documents to appear in a pop-up, but also
|   selected elements of the current document (e.g.,the NOTE and FN
|   elements that were once proposed.)
Yes; in my previous note I pointed out that there should be a structural
(tagging) method of indicating that something is an out-of-line element
(like a footnote or sidebar) *and* there should be a stylesheet
mechanism for controlling the detailed appearance of that element (e.g.,
popup-style: separate-window | separate-pane | frame (if frame, another
property would need to carry the frame name).
| - does the pop up need a title?
Yes (should be attribute of the tag).
| - do we want to specify whether it has an `OK' button or something
|   else?
It *could* have HTML hyperlink buttons if appropriate, but functional
buttons (like "dismiss") should be left to the browser.  That is, the
"explicit-dismiss" style, above, means the browser should use its native
visual style to offer a dismissal option, while the "persistent-window"
style means an independent browser window.
| This causes minimal disruption to the user interface and assures that
| at all times there is at most one pop-up and that it stays open for a
| short time only.
Both false goals - if the popup is for a sidebar, the whole idea is to
allow a separate nagivation around the sidebar topic without disrupting
the "base" browsing that was going on before the sidebar was opened.  I
see no reason this should be limited to one window (the sidebar could
have footnotes) or that its duration should not be independent of the
duration of the page that led to opening it.

This all obviously intersects in some ways with the FRAME model, if one ends
up in the standard, and details would need to be coordinated.
| It is also easy to replace with something else in browsers that don't
| do pop-ups (because they don't run under a windowing system, or
| otherwise). You can put the would-be pop-up between two thick black
| lines in the text, you can have a reserved screen space for them, you
| can have them temporarily replace the current document, etc.
This is also possible without the restrictions.


scott preece
motorola/mcg urbana design center	1101 e. university, urbana, il   61801
phone:	217-384-8589			  fax:	217-384-8550
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