QT modules

java 에서는 package라고 하고
qt 에서는 module 이라고 하나보다

아무튼 module 이름으로 include 하면된다.
#include <Qtgui> 

Modules for general software development
QtCore	Core non-graphical classes used by other modules
QtGui	Graphical user interface (GUI) components
QtMultimedia	Classes for low-level multimedia functionality
QtNetwork	Classes for network programming
QtOpenGL	OpenGL support classes
QtOpenVG	OpenVG support classes
QtScript	Classes for evaluating Qt Scripts
QtScriptTools	Additional Qt Script components
QtSql	Classes for database integration using SQL
QtSvg	Classes for displaying the contents of SVG files
QtWebKit	Classes for displaying and editing Web content
QtXml	Classes for handling XML
QtXmlPatterns	An XQuery & XPath engine for XML and custom data models
QtDeclarative	An engine for declaratively building fluid user interfaces.
Phonon	Multimedia framework classes
Qt3Support	Qt 3 compatibility classes
Modules for working with Qt's tools
QtDesigner	Classes for extending Qt Designer
QtUiTools	Classes for handling Qt Designer forms in applications
QtHelp	Classes for online help
QtTest	Tool classes for unit testing
Modules for Windows developers
QAxContainer	Extension for accessing ActiveX controls
QAxServer	Extension for writing ActiveX servers
Modules for Unix developers
QtDBus	Classes for Inter-Process Communication using the D-Bus

[링크 : http://qt-project.org/doc/qt-4.8/modules.html]