Re: suggesting a book or tutorial for learning gtkmm 3.0
I think the Gnome Developer Center tutorials are excellent and you'll struggle to find better for gtkmm. The gtkmm tutorials have screenshots and examples for most of the controls, which is the bulk of what you need really.
You'll probably find GTK2 books but GTK3 is relatively new. GTK is almost a programming language in it's own right, so any GTK2/GTK3 tutorials will give you useful techniques in any language. You just need to validate any deprecated controls against the GTK3 reference.
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