A presentation on cross platform development using Qt help on the second foss-sthlm meeting.

1. Cross Platform Qt Johan Thelin

3. Articles, whitepapers, etc

5. Co-organizes FSCONS embedded November 5-7

6. The History of Qt

8. For creating portable application source code – one source, multiple platforms

9. Produces native applications

11. Trolltech founded in 1994

12. Acquired by Nokia 2008

13. Nokia Qt Development Frameworks

16. 2009 all platforms released under LGPL

18. Create More

19. Deploy Everywhere

20. The Architecture of Qt

21. The Modules of Qt QtGui QtSql QtNetwork QtWebKit QtSvg QtOpenGL QtOpenVG QtMultimedia QtScript QtXml QtXmlPatterns Phonon QtDBus QtTest

23. Can be activated or disabled at compile time

24. Allows tweaking of feature set and footprint

25. As easy as CONFIG += sql network

26. All modules share the Qt API design

27. All modules fit together

29. Signals and slots

30. Introspection

31. Properties

33. Parents delete all children upon destruction MyDialog::MyDialog(QWidget * parent ) : QDialog( parent ) { QPushButton *okButton = new QPushButton( this ); QPushButton *cancelButton = new QPushButton( this ); ... } MyWindow::useDialog() { MyDialog dlg(this); if(dlg.exec() == QDialog::Accepted) ... }

35. Works seamless across thread boundaries

36. Creates re-usable components class QPushButton : ... { ... signals : void clicked(); ... }; class QListWidget : ... { ... public slots : void clear(); ... }; connect (button, SIGNAL(clicked()), list, SLOT(clear()));

38. Signals and function pointer tables, etc are generated by the meta object compiler, moc

39. Invoked at compile time and generates additional vanilla C++ source code emit clicked();

42. Great when creating language bindings

43. Makes RTTI work across library boundaries

45. Great when binding to dynamic languages

46. Great when serializing objects

47. Can be used to add extra information to existing classes. Useful in combination with visitor classes class QLabel : ... { Q_PROPERTY (QString text READ text WRITE setText ...) ... }

50. Large community

51. High quality code

52. etc

53. Qt Today

55. Google Earth

56. Nokia N900

58. Windows

59. Mac OS X

60. Embedded Linux

61. Windows CE

62. Symbian

64. Haiku

65. OS/2

66. iPhone

67. Android

68. webOS

69. Kindle DX

70. QNX

71. wxWorks

73. C# (.net)

74. Ada

75. Java

76. JavaScript

77. Lisp

78. Lua

79. Perl

80. PHP

81. Python

82. Ruby

84. The QtScript module enables JavaScript integration

85. PyQt is very popular

86. The smoke bindings generator from KDE makes it easy to create more bindings

88. The goal of Qt is to blend in everywhere

89. Portability Tips and Tricks

90. Portability - Interfaces QStyle QCommonStyle QMotifStyle QWindowStyle QS60Style QProxyStyle QCDEStyle QMacStyle QPlastiqueStyle QWindowsXPStyle QCleanlooksStyle QGtkStyle QWindowsVistaStyle

92. Portability - Backends ... QPainter QPaintEngine QRasterPaintEngine X11 Windows OpenGL SVG

95. QMouseDriverPlugin

99. Qt::WindowSystemMenuHint Mac OS X specific dialogs, gives you an ordinary dialog or window on other platforms.

101. Documentation: “ Indicates that the window is a Macintosh sheet. Since using a sheet implies window modality, the recommended way is to use QWidget::setWindowModality()... ” MyDialog::MyDialog(QWidget *parent) : QWidget(parent, Qt::Sheet ) { setWindowModality(Qt::WindowModal); ...

103. It is possible to tweak the Qt build system to link against different libraries on different platforms

104. It is possible to enable or disable individual classes to streamline Qt

105. ... bool QWidget::x11Event (XEvent *event)

107. As long as you stick to Qt APIs you do not have to worry about platforms – it just works

108. Thank you for your attention! [email_address]