C++ GUI Programming with Qt 4, 2nd Edition

Qt is a comprehensive C++ application development framework for creating cross-platform GUI applications using a "write once, compile anywhere" approach. Qt lets programmers use a single source tree for applications that will run on Windows 98 to Vista, Mac OS X, Linux, Solaris, HP-UX, and many other versions of Unix with X11. The Qt libraries and tools are also part of Qt/Embedded Linux, a product that provides its own window system on top of embedded Linux.\ The purpose of this book is to teach you how to write GUI programs using Qt 4. The book starts with "Hello Qt" and quickly progresses to more advanced topics, such as creating custom widgets and providing drag and drop. The text is complemented by a set of examples that you can download from the book's web site, http://www.informit.com/title/0132354160. Appendix A explains how to download and install the software, including a free C++ compiler for those using Windows.\ The book is divided into three parts. Part I covers all the fundamental concepts and practices necessary for programming GUI applications using Qt. Knowledge of this part alone is sufficient to write useful GUI applications. Part II covers central Qt topics in greater depth, and Part III provides more specialized and advanced material. You can read the chapters of Parts II and III in any order, but they assume familiarity with the contents of Part I. The book also includes several appendixes, with Appendix B showing how to build Qt applications and Appendix C introducing Qt Jambi, the Java version of Qt.\ The first Qt 4 edition of the book built on the Qt 3 edition, although it was completely revised to reflect good idiomatic Qt 4 programming techniques and included new chapters on Qt 4's model/view architecture, the new plugin framework, embedded programming with Qt/Embedded Linux, and a new appendix. This extended and revised second edition has been thoroughly updated to take advantage of features introduced in Qt versions 4.2 and 4.3, and includes new chapters on look and feel customization and application scripting as well as two new appendixes. The original graphics chapter has been split into separate 2D and 3D chapters, which between them now cover the new graphics view classes and QPainter's OpenGL back-end. In addition, much new material has been added to the database,\ This edition, like its predecessors, emphasizes explaining Qt programming and providing realistic examples, rather than simply rehashing or summarizing Qt's extensive online documentation. Because the book teaches solid Qt 4 programming principles and practices, readers will easily be able to learn the new Qt modules that come out in Qt 4.4, Qt 4.5, and later Qt 4.x versions. If you are using one of these later versions, be sure to read the "What's New in Qt 4.x" documents in the reference documentation to get an overview of the new features that are available.\ We have written the book with the assumption that you have a basic knowledge of C++, Java, or C#. The code examples use a subset of C++, avoiding many C++ features that are rarely needed when programming Qt. In the few places where a more advanced C++ construct is unavoidable, it is explained as it is used. If you already know Java or C# but have little or no experience with C++, we recommend that you begin by reading Appendix D, which provides sufficient introduction to C++ to be able to use this book. For a more thorough introduction to object-oriented programming in C++, we recommend C++ How to Program by P. J. Deitel and H. M. Deitel (Prentice Hall, 2007), and C++ Primer by Stanley B. Lippman, Jos¿Lajoie, and Barbara E. Moo (Addison-Wesley, 2005).\ Qt made its reputation as a cross-platform framework, but thanks to its intuitive and powerful API, many organizations use Qt for single-platform development. Adobe Photoshop Album is just one example of a mass-market Windows application written in Qt. Many sophisticated software systems in vertical markets, such as 3D animation tools, digital film processing, electronic design automation (for chip design), oil and gas exploration, financial services, and medical imaging, are built with Qt. If you are making a living with a successful Windows product written in Qt, you can easily create new markets in the Mac OS X and Linux worlds simply by recompiling.\ Qt is available under various licenses. If you want to build commercial applica-tions, you must buy a commercial Qt license from Trolltech; if you want to build open source programs, you can use the open source (GPL) edition. The K Desktop Environment (KDE) and most of the open source applications that go with it are built on Qt.\ In addition to Qt's hundreds of classes, there are add-ons that extend Qt's scope and power. Some of these products, like the Qt Solutions components, are avail-able from Trolltech, while others are supplied by other companies and by the open source community; see http://www.trolltech.com/products/qt/3rdparty/ for a list of available add-ons. Trolltech's developers also have their own web site, Trolltech Labs (http://labs.trolltech.com/), where they put unofficial code that they have written because it is fun, interesting, or useful. Qt has a well-established and thriving user community that uses the qt-interest mailing list; see http://lists.trolltech.com/ for details.\ If you spot errors in the book, have suggestions for the next edition, or want to give us feedback, we would be delighted to hear from you. You can reach us at qt-book@trolltech.com. The errata will be placed on the book's web site http://www.informit.com/title/0132354160.

Series Editor's Note     xiForeword     xiiiPreface     xvAcknowledgments     xviiA Brief History of Qt     xixBasic QtGetting Started     3Hello Qt     3Making Connections     5Laying Out Widgets     6Using the Reference Documentation     10Creating Dialogs     13Subclassing QDialog     13Signals and Slots in Depth     20Rapid Dialog Design     23Shape-Changing Dialogs     31Dynamic Dialogs     38Built-in Widget and Dialog Classes     39Creating Main Windows     45Subclassing QMainWindow     46Creating Menus and Toolbars     50Setting Up the Status Bar     55Implementing the File Menu     57Using Dialogs     63Storing Settings     69Multiple Documents     71Splash Screens     74Implementing Application Functionality     77The Central Widget     77Subclassing QTableWidget     78Loading and Saving     84Implementing the Edit Menu     87Implementing the Other Menus     91Subclassing QTableWidgetItem     95Creating Custom Widgets     105Customizing Qt Widgets     105Subclassing QWidget     107Integrating Custom Widgets with Qt Designer     117Double Buffering     121Intermediate QtLayout Management     141Laying Out Widgets on a Form     141Stacked Layouts     147Splitters     149Scrolling Areas     152Dock Windows and Toolbars     154Multiple Document Interface     157Event Processing     167Reimplementing Event Handlers     167Installing Event Filters     172Staying Responsive during Intensive Processing     1752D Graphics     179Painting with QPainter     180Coordinate System Transformations     185High-Quality Rendering with QImage     193Item-Based Rendering with Graphics View     195Printing     217Drag and Drop     227Enabling Drag and Drop     227Supporting Custom Drag Types     232Clipboard Handling      237Item View Classes     239Using the Item View Convenience Classes     240Using Predefined Models     247Implementing Custom Models     252Implementing Custom Delegates     266Container Classes     273Sequential Containers     274Associative Containers     282Generic Algorithms     285Strings, Byte Arrays, and Variants     287Input/Output     295Reading and Writing Binary Data     296Reading and Writing Text     301Traversing Directories     307Embedding Resources     308Inter-Process Communication     309Databases     315Connecting and Querying     316Viewing Tables     322Editing Records Using Forms     324Presenting Data in Tabular Forms     330Multithreading     339Creating Threads     340Synchronizing Threads     343Communicating with the Main Thread     349Using Qt's Classes in Secondary Threads     356Networking     359Writing FTP Clients     359Writing HTTP Clients      368Writing TCP Client-Server Applications     371Sending and Receiving UDP Datagrams     381XML     387Reading XML with QXmlStreamReader     388Reading XML with DOM     395Reading XML with SAX     400Writing XML     404Providing Online Help     407Tooltips, Status Tips, and "What's This?" Help     407Using a Web Browser to Provide Online Help     409Using QTextBrowser as a Simple Help Engine     411Using Qt Assistant for Powerful Online Help     414Advanced QtInternationalization     419Working with Unicode     420Making Applications Translation-Aware     423Dynamic Language Switching     429Translating Applications     435Look and Feel Customization     439Using Qt Style Sheets     439Subclassing QStyle     4543D Graphics     471Drawing Using OpenGL     471Combining OpenGL and QPainter     477Doing Overlays Using Framebuffer Objects     484Creating Plugins     491Extending Qt with Plugins     492Making Applications Plugin-Aware      502Writing Application Plugins     505Application Scripting     509Overview of the ECMAScript Language     510Extending Qt Applications with Scripts     519Implementing GUI Extensions Using Scripts     523Automating Tasks through Scripting     530Platform-Specific Features     543Interfacing with Native APIs     543Using ActiveX on Windows     547Handling X11 Session Management     559Embedded Programming     567Getting Started with Qt/Embedded Linux     568Customizing Qt/Embedded Linux     570Integrating Qt Applications with Qtopia     571Using Qtopia APIs     576AppendixesObtaining and Installing Qt     589Building Qt Applications     593Introduction to Qt Jambi     605Introduction to C++ for Java and C# Programmers     623Index     665