269473 - Improve the use of sheets

Status: RESOLVED INCOMPLETE

(Core Graveyard :: Widget: Mac, defect)

Description

[jhp (no longer active)]

There are many bugs open on the misuse of sheets on Mac OS X versions of Gecko
browsers.  But they usually refer to a specific dialog, so I decided to open up
this all encompassing bug.

Basically, this is a spinoff from bug 257546.  As mentioned in
https://bugzilla.mozilla.org/show_bug.cgi?id=257546#c6 by Asaf, the problem is
that we use sheets for modal windows, and we can't display modal-but-non-sheet
windows.  Asaf puts forth one solution to the problem.

However, I don't think that goes far enough.  Both the current implementation
and Asaf's suggestion attempt to guess when a sheet should be used.  I'd like to
be more explicit about.  Let's split the "modal" keyword into two:  "app-modal"
and "document-modal".  This would be a cross-platform change, so other operating
systems could take advantage.  In the OS X case, a window specified as
"app-modal" would be a regular modal window.  Those specified as
"document-modal" would be sheets.  So the prefs window in Firefox would be
"app-modal", and the save dialogs would be sheets.

How does that sound?

Comment 1

[Boris Zbarsky [:bzbarsky]]

That sounds like a pretty good idea to me (with "modal" support left in because
some apis that use it are frozen, I guess...)

Comment 2

[jhp (no longer active)]

bz: Yes, that's what I was thinking: "app-modal" & "modal" for regular modal
windows, and "document-modal" (or "doc-modal") for document specific modal dialogs.

Comment 3

[Boris Zbarsky [:bzbarsky]]

Er... except "modal" means "window-modal", not "app-modal" on non-mac platforms.