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diff --git a/examples/widgets/doc/factorial.qdoc b/examples/widgets/doc/factorial.qdoc new file mode 100644 index 0000000000..82ab5da536 --- /dev/null +++ b/examples/widgets/doc/factorial.qdoc @@ -0,0 +1,88 @@ +/**************************************************************************** +** +** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies). +** Contact: http://www.qt-project.org/ +** +** This file is part of the documentation of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:FDL$ +** GNU Free Documentation License +** Alternatively, this file may be used under the terms of the GNU Free +** Documentation License version 1.3 as published by the Free Software +** Foundation and appearing in the file included in the packaging of +** this file. +** +** Other Usage +** Alternatively, this file may be used in accordance with the terms +** and conditions contained in a signed written agreement between you +** and Nokia. +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +/*! + \example statemachine/factorial + \title Factorial States Example + + The Factorial States example shows how to use \l{The State Machine + Framework} to calculate the factorial of an integer. + + The statechart for calculating the factorial looks as follows: + + \image factorial-example.png + \omit + \caption This is a caption + \endomit + + In other words, the state machine calculates the factorial of 6 and prints + the result. + + \snippet statemachine/factorial/main.cpp 0 + + The Factorial class is used to hold the data of the computation, \c x and + \c fac. It also provides a signal that's emitted whenever the value of \c + x changes. + + \snippet statemachine/factorial/main.cpp 1 + + The FactorialLoopTransition class implements the guard (\c x > 1) and + calculations (\c fac = \c x * \c fac; \c x = \c x - 1) of the factorial + loop. + + \snippet statemachine/factorial/main.cpp 2 + + The FactorialDoneTransition class implements the guard (\c x <= 1) that + terminates the factorial computation. It also prints the final result to + standard output. + + \snippet statemachine/factorial/main.cpp 3 + + The application's main() function first creates the application object, a + Factorial object and a state machine. + + \snippet statemachine/factorial/main.cpp 4 + + The \c compute state is created, and the initial values of \c x and \c fac + are defined. A FactorialLoopTransition object is created and added to the + state. + + \snippet statemachine/factorial/main.cpp 5 + + A final state, \c done, is created, and a FactorialDoneTransition object + is created with \c done as its target state. The transition is then added + to the \c compute state. + + \snippet statemachine/factorial/main.cpp 6 + + The machine's initial state is set to be the \c compute state. We connect + the QStateMachine::finished() signal to the QCoreApplication::quit() slot, + so the application will quit when the state machine's work is + done. Finally, the state machine is started, and the application's event + loop is entered. + + */ |