On Tue, 8 Dec 2020 08:41:58 +0100 Kjell Ahlstedt <kjellahlstedt gmail com> wrote:I don't know if it works with a file that glade has written.That sounds like you don't support glade. I am confused, because I thought that glade was the defacto standard that Gnome wants users to generate user interfaces.
Gtkmm supports glade, if gtk supports glade. Gtkmm just wraps gtk's C functions in C++ code. The glade file with a GtkDialog that you mention should be no problem for gtkmm. It's similar to the https://gitlab.gnome.org/GNOME/gtkmm-documentation/-/tree/gtkmm-3-24/examples/book/builder/basic example.
A glade file with GtkRadioMenuItem can probably also be used. If I had realized from the beginning that you're not interested in the kind of solution I gave you, I might have managed to get something working without touching the ui_info string. There is a limit to how much time I want to spend trying to answer your questions. That's a drawback with free open source code: When you get stuck, no one is responsible for answering your questions.