qt4 apps such as vlc: QGtkStyle was unable to detect the current GTK+ theme unless libgnome2-common is installed

Status changed to 'Confirmed' because the bug affects multiple users.

Took a look at which package 'fixed' this in a unity session
Installing just libgnome2-common removes the error & let's vlc theme ok with unity/ambiance

Specifically desktop_gnome_interface.schemas

(Putting just that file back & getting " Processing triggers for gconf2 .." & or some other "triggers" fixes here

I have removed the tag regression-update from this bug report as the tag should be used for a regression which happened when installing a package from the -updates repository. This tag is used by the Stable Release Updates team to watch for regressions in packages from -updates and inappropriate usage of this tag makes it harder to find this category of regression. Thanks for your understanding. To learn more about how we use tags you may want to review http://wiki.ubuntu.com/Bugs/Tags.

This bug is not limited to vlc, in fact I'm experiencing the same issue running minitube. In this case installing libgnome2-common is not a solution because, although the theme becomes Gtk, all icons keep missing.

Same bug with Qbittorrent and Smplayer. Ubuntu 13.04 (updated).

From a Qt POV we could only make a package suggest on gnome2-common which does not change the situation other than there being a message (when using apt-get!) that one might want t install gnome2-common too. So it probably would be better to have this pulled in by ubuntu-desktop.

This is true for all Qt applications on raring and should therefore be valued "high".

Installing libgnome2-common fixes the problem for vlc, skype versions that are in default ubuntu 13.04 repos.

That's because of https://bazaar.launchpad.net/~ubuntu-branches/ubuntu/raring/qt4-x11/raring/view/head:/src/gui/styles/qgtkstyle_p.cpp#L688. I'm working on a fix for Qt 5, but I'm not sure if it will be backportable to Qt 4.

This bug also happens with Guitar Pro 6 which i believe uses QT 4, even though libgnome2-common is installed. It will not launch beyond the greeting screen.

I've tried to ping Kubuntu developers about this branch without any success, so subscribing ~ubuntu-sponsors to get the fix at least uploaded. Note that the branch also fixes a FTBFS.

For those who want to test the fix, updated packages are available in ppa:mitya57/test2.

Works fine here, (ppa), tested fresh install with vlc, smplayer

Core devs have upload rights into ~kubuntu-packages. So you should have earlier subscribe sponsors on the bug report, or request review from ubuntu branches on the merge proposal (like for UDD branches).

This bug was fixed in the package qt4-x11 - 4:4.8.4+dfsg-0ubuntu8

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qt4-x11 (4:4.8.4+dfsg-0ubuntu8) raring; urgency=low

  [ Harald Sitter ]
  * Drop kdeqt.pot creation. Not used anymore (fixes build with new
    pkg-kde-tools)

  [ Dmitry Shachnev ]
  * debian/patches/kubuntu_41_remove_gtk_theme_check.diff:
    do not check that Gtk theme is not empty (LP: #1094360).
 -- Harald Sitter <email address hidden> Mon, 18 Mar 2013 11:10:45 +0100

This is also fixed upstream now, see https://qt.gitorious.org/qt/qt/commit/a9dc50330acee2ac.