Home

Step 1

Mark these words with fire and iron: You do not call GUI functions from another thread. You only do that from the main thread(also called gui thread). You could do it from another thread but you need to acquire some specific GDK locks first, if I remember correctly. https://ubuntuforums.org/showthread.php?t=2103045

Further reading:

• See an example of multi-threading. Note the use of Glib::Dispatcher: https://developer.gnome.org/gtkmm-tutorial/stable/sec-multithread-example.html.en
• Using a Glib::Dispatcher: https://developer.gnome.org/gtkmm-tutorial/stable/sec-using-glib-dispatcher.html.en