Chapter 3. The Qt Toolkit

by Daniel Marjamäki

In This Chapter

KDE is built on Qt, so the KDE programmer must know Qt. Even if you use only KDE widgets in your programs, you should know something about Qt.

The Qt toolkit is a collection of classes that simplify the creation of programs. The classes are both visible (buttons, windows) and invisible (timer).

This chapter won't cover all features of the Qt toolkit. The most important topics are here, but you may need more information eventually. You can find more information on the Trolltech Web site (

3.1. What It Is For (Look and Feel)

X Windows programming, the traditional way, is both time consuming and hard. The Qt toolkit makes it easier and faster to create X Window programs.


Another good feature of Qt is that you can recompile your code for different desktops (X Window, MS Windows).

A good program must have an easy-to-understand and easy-to-use user interface. Qt provides several widgets, which can give your programs such an interface. Widgets are controls such as buttons, windows, text boxes, list boxes, and so on.