This book explains key concepts of the gtkmm C++ API for creating user interfaces. It also introduces the main user interface elements ("widgets"). Although it mentions classes, constructors, and methods, it does not go into great detail. Therefore, for full API information you should follow the links into the reference documentation.
This book assumes a good understanding of C++, and how to create C++ programs.
We would very much like to hear of any problems you have learning gtkmm with this document, and would appreciate input regarding improvements. Please see the Contributing section for further information.