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An Introduction to Qt 4

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An Introduction to Qt 4 AnAn IntroductionIntroduction toto QtQt 44 Jason Trent [email protected] OOuutltliinnee . Why Trolltech? . Why Qt? . Qt 4 Widgets, Datatypes, and Structures . Qt Designer . qmake . Qt without C++ . Demo WWhhyy TTrroolllltetecchh?? .. QQtt aanndd QQttooppiiaa CCoorree aarree OOppeenn SSoouurrccee .. SSuuppppoorrtteedd bbyy mmuullttii--mmiilllliioonn ddoollllaarr ccoommppaannyy WWhhyy QQt?t? .. MMuullttii--ppllaattffoorrmm – No “virtual machines” or emulation layers – Native compilation for Windows, X11, and Mac • Utilizes core OS technologies (Core, Aero, …) – Extensions - ActiveQt, Motif Migration WWhhyy QQt?t? Over 400 C++ Classes . Not just a GUI toolkit – File handling – Networking – Process handling – Threading – Database access – Event loop processing – XML processing – OpenGL integration – and beyond WWhhyy QQt?t? .. IInntteerrnnaattiioonnaalliizzaattiioonn – Built in support for Unicode and Translation • Language and font aware layouts • Bidirectional font support • Mixed-international interface .. SSeeee QQtt LLiinngguuiisstt ffoorr mmoorree WWhhyy QQt?t? .. NNoott jjuusstt mmuuttllii--ppllaattiiffoorrmm,, mmuullttii--aarrcchhiitteeccttuurree .. QQttooppiiaa CCoorree 44 SSeerriieess – Support for embedded devices • Cell phones, PDAs, etc… – Supports Qt4 widgets with little to no code change QQWWiiddggeett TThhee mmeeeekk mmaayy iinnhheerriitt tthhee eeaarrtthh…… ……bbuutt tthhee eeaarrtthh sshhaallll iinnhheerriitt QQWWiiddggeett QWidget QQtt 44 WWiiddggeetsts .. IInnhheerriitt tthhee aallll--ppoowweerrffuull QQWWiiddggeett .. IInncclluuddee:: – QLabel – QPushButton – QTextBox – QDialog – QFileDialog – Many, many more SSiiggnnaallss aanndd SSllootsts .. PPrroovviiddee ccoommmmuunniiccaattiioonn bbeettwweeeenn oobbjjeeccttss .. AA ssiiggnnaall iiss eemmiitttteedd aanndd sslloottss rreeaacctt .. GGeetttteerrss aanndd SSeetttteerrss .. FFuunnccttiioonnss QQtt 44 DDaatatatytyppeess && SStrtruucctuturreess .. AAddvvaanncceedd ddaattaattyyppeess – QString – QDataStream .. SSttrruuccttuurreess – QList – QVector – QMap QQtt DDeessiiggnneerr . Powerful stand-alone interface builder . Ability to integrate into IDEs – Kdevelop, Visual Studio, … . Ability to preview on target platforms – Windows, Windows XP, Mac, Plastique, CDE, and Motif . Extensive layout system – Auto-scaling, font-aware layouts – Dynamically adjust layout for font size, direction, display size, language, operating system qqmmaakkee .. OOnnee pprroojjeecctt ffoorrmmaatt ttoo rruullee tthheemm aallll .. MMaaiinnttaaiinn ..pprroo pprroojjeecctt ffiillee – Automatically create target project • Makefile • XCode • Visual Studio TEMPLATE = app <!DOCTYPE RCC><RCC version="1.0"> INCLUDEPATH += . <qresource> QT += core gui network <file>images/logo.png</file> TARGET = iBoard <file>images/logo_mask.bmp</file> <file>images/save.png</file> # Input <file>images/clear.png</file> HEADERS += canvas.h \ <file>images/pencil.png</file> netconnect.h \ <file>images/pencil_mask.bmp</file> scMakefileribble.h <file>images/eraser.png</file> <file>images/eraser_mask.bmp</file> FORMS += staXCodertup4.ui Project (. x codeproj<file>images/)fill.png</file> <file>images/fill_mask.bmp</file> SOURCES += caVisualnvas.cpp \Studio (.v cproj <file>)images/print.png</file> netconnect.cpp \ </qresource> scribble.cpp \ </RCC> main.cpp RESOURCES = iBoard.qrc qqmmaakkee CCoommmmaanndd LLiinnee OOpptitioonnss .. --pprroojjeecctt – Auto-generate .pro file based on folder contents .. --ssppeecc [[mmaakkeessppeecc]] – Build the project or make file based on the make specification • linux-g++, macx-xcode, win32-mingw, … DemoDemo OOththeerr IteItemmss ooff InInteterreesstt .. PPyyQQtt -- QQtt eexxtteennssiioonnss ffoorr PPyytthhoonn .. PPeerrllQQtt -- QQtt eexxtteennssiioonnss ffoorr PPeerrll .. QQtt//JJaavvaa -- TTrroolllltteecchh ssuuppppoorrtteedd JJaavvaa eexxtteennssiioonnss – Coming Q1 2006 RReefeferreenncceess . Trolltech www.trolltech.com . Qt Forum www.qtforum.org . The Qt4 Resource Center qt4.digitalfanatics.org . Qt Centre www.qtcentre.org . C++ GUI Programming in Qt 3 www.phptr.com/perens . Slide format and many images from Trolltech Code Less. Create More..
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