GNOME Bugzilla – Bug 150594
ability to "flash" buttons
Last modified: 2013-10-06 06:25:53 UTC
See bug 120439, specifically comment 12 by Owen. It appears that the gtk theme would need to be extended in some way before that bug can be resolved. See also bug 148370 for another case that is similar where this behavior could be wanted.
Well, it depends on how you want to flash the button, but what I was saying in the comment you reference was not: GtkButton can't draw itself in a different state because the theme won't allow it But rather: An application can't change the state underneath the back of GtkButton. Now there may be a separate problem that if you start drawing buttons in states themes aren't used to, they may not have the code to draw it correctly, but that isn't a theme system issue, and not really a GTK+ issue. Retitling the bug, though I'm not completely sold that a gtk_button_flash() is a useful thing.
*** Bug 168590 has been marked as a duplicate of this bug. ***
we have the ability to do things like this now, see e.g. the flashing updates button in gnome-software. It works by adding a suitable style class