QT allows you to write programs that run on multiple operating system. Unless you’ve any commercial intentions you can always use QT to get your small projects or open source projects to work with your C++ programming skills. Other than C++ language, QT also supports java and Python with additional language bindings. Java supported release is known as jambi and is suitable for those who are interested in java development over desktop. If you’re beginner C++ programmer and wants to delve into QT programming for cross platform open source applications then take a look at following books for starters.
This book has very friendly approach towards newbie c++ programmers and teaches you how to get going with QT classes and GUI in smooth flow. You’ll not find much of theory stuff in there which is good if you’re practical programmer. Though there is not much of advanced stuff covered like systems programming or mobile app etc but it is aimed at beginners so the information amount and flow reflects to that.
This book from prentice hall authors is focused on intermediate developers. Some chapters are reserved for some intro to QT framework and it’s immediate use and rest of the chapters covers tips and information on how to get more out of QT. This book is good for those who like less-guided approach towards framework.
To be honest this book is showcase of what’s inside QT framework than any guide or reference book. It just shows you what things are available in the framework and what is possible (as of now) with QT. I do expect a better deal from books than being mere a showcase. So if you’re one of those theory book absorber then you’ll find this book handy.
Other than the above mentioned book, you should also take a look at online documentation and tutorials. There is also QT forum for developers where your questions will be answered by other developers. Feel free to lurk around those resources other than reading books if you’re interesting in QT development.