Revert GtkAdjustment clamping change?
cjwatson at ubuntu.com
Thu Sep 18 03:02:30 BST 2008
I was lucky enough to notice this changelog entry during an upgrade:
gnome-system-tools (2.22.0-1ubuntu2) intrepid; urgency=low
* GtkAdjustment behaviour has changed to restrict the range of the values.
From the GTK README:
GtkAdjustment now enforces that values are restricted to the
range [lower, upper - page_size]. This has always been the
documented behaviour, and the recommended practice is to set
page_size to 0 when using adjustments for simple scalar values,
like in a slider or spin button.
This change meant that the time couldn't be set to greater than 13:49:49,
as the upper was 23:59:59 and the page_sizes 10:10:10.
debian/patches/91_time_admin_adjustment.patch corrects this by reducing
the page_sizes to 0, as recommended in the above quote.
-- James Westby <james.westby at canonical.com> Thu, 11 Sep 2008 00:18:54 +0100
Thanks to James for the excellently clear changelog entry! The same
problem turned out to be responsible for a small collection of very
serious bugs in Ubiquity's manual partitioner (see the referenced LP bug
and its duplicates):
ubiquity (1.9.15) intrepid; urgency=low
* GTK frontend:
- Don't set page_size in GtkAdjustments; as of GTK+ 2.14 it causes the
value to be clamped to upper - page_size (LP: #264599).
-- Colin Watson <cjwatson at ubuntu.com> Wed, 17 Sep 2008 03:06:59 +0100
As I just pointed out in the upstream bug (although it's on
gnome-system-tools rather than GTK+), the documentation of this
behaviour is *not* clear; the only place I could find where it's
actually documented as described in the release notes is in the source
code, and the HTML documentation almost outright contradicts it. Thus I
expect that many applications will have problems with this. Milosz
Derezynski already pointed out a couple in the upstream bug, and I can
confirm that at least our Inkscape package currently suffers from a
So, two questions:
* Could somebody do a source code scan of the Ubuntu archive (at least
main) to try to find instances of this problem? Searching for
"page_size" (possibly only in files also containing "Adjustment", if
the former alone produces too many false positives) should be good
enough to assemble a hit-list to check by hand.
* Could we please revert this change in our GTK+ packaging for the
meantime, at least until we get an idea of the scale of the problem?
Colin Watson [cjwatson at ubuntu.com]
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