113283 - dependent window placement improvements

Status: RESOLVED FIXED

(Core :: XUL, defect)

Description

[Dan M]

Maybe it's time for some long overdue improvements to the window placement code.

Comment 1

[Dan M]

Attachment: window placement enhancements

(1) Centers dependent windows on their parent instead of on their parent's
screen, (2) Persists dependent window positions relative to their parent
instead of globally, and (3) allows position persistence to override centering.

  Note (1) had already been implemented, but had some bugs. This fixes them.
(3) allows a window to be both centered and given position persistence. It will
show up centered the first time, and on subsequent times, in its saved
position.
  Note also we still don't have a full suite of window centering options. This
patch reinterprets the window.open feature "centerscreen" to mean "center on
parent." Alternatively we could enrich the window.open feature set but I resist
doing that because of the 32 bitfield parameter we reduce the string to. While
we do (currently) have the bits to spare, still a bunch of centering options
seem out of place. I've chosen to wing it with a heuristic, instead.

Comment 2

[Boris Zbarsky [:bzbarsky]]

How does item (1) interact with parents whose center is off the screen?  Does
the dependent window appear (partially) off the screen?

Comment 3

[Dan M]

Probably. There is already code to keep windows at least partially onscreen, but
it'll allow quite a bit. I'll need to teach the widget code to force a dependent
window to remain entirely onscreen. That complicates things a bit...

Comment 4

[Boris Zbarsky [:bzbarsky]]

Another twist is that dependents of parents which are entirely offscreen (eg
multiple-desktop setup on Unix or Windows) should be fine popping up offscreen,
right?

Popping them up on a different desktop from the parent could be a little
confusing.

Comment 5

[Dan M]

Attachment: dependent window placement enhancements

This patch same as before except dependent windows are pinned entirely on the
same screen as the parent window, and I've enabled it on unix builds too
(dependent/transient windows, only -- independent windows remain placed by the
window manager) because of bug 112495, a fix for which this patch should lay
the groundwork. Yes, Yoda I channel.

Note that only the first ten files changed in the patch are important. The
remainder are just tweaks necessary because I'm changing an interface.

Comment 6

[Dan M]

.

Comment 7

[[not reading bugmail]]

see bug 119141 for a regression from this.