[Bug 1846699] [NEW] Missing mechanism in Glibmm that prevents the support of some themes (CSS) in Gtkmm

[Launchpad Bug Tracker]

You have been subscribed to a public bug by Sebastien Bacher (seb128):

In  GTK+ 3.20 the theming mechanics was heavily changed.

https://developer.gnome.org/gtk3/stable/ch32s10.html

One of the major changes was the use of element names much more than
style classes. For this the function gtk_widget_class_set_css_name() was
added to t he API and used to assign the element names. However, this
was not added in GTKmm, making impossible to assign element names in
custom widget, and no automatically assignment was developed in GTKmm's
Widget class in order to be able to identify widget classes in the
theming system (CSS).

The problem was discussed and tracked up to Glibmm in GNOME bug tracking
system:

https://gitlab.gnome.org/GNOME/gtkmm/issues/17
https://gitlab.gnome.org/GNOME/glibmm/issues/33

The issues are due to the lack of the mechanism to call
gtk_widget_class_set_css_name() function in the instance init function.

This was solved in Glibmm2.4 2.60, however Ubuntu is still behind this
version and it's affecting some of our products.

We have applied a patch to the current version (2.56) of Glibmm2.4 in
Ubuntu 18.04 successfully, but I would like to ask you to consider
upgrading the version of Glibmm in the official repository or apply the
patch.

** Affects: glibmm2.4 (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: patch
-- 
Missing mechanism in Glibmm that prevents the support of some themes (CSS) in Gtkmm
https://bugs.launchpad.net/bugs/1846699
You received this bug notification because you are a member of Ubuntu Sponsors Team, which is subscribed to the bug report.