cd46a2daf5
Update files using old header.LGPL3 to header.LGPL Update files using old FDL template to use new one Update files using old BSD template to use new one Change-Id: I36a78272516f9953d02956522f285b40adfc8915 Reviewed-by: Lars Knoll <lars.knoll@theqtcompany.com>
89 lines
3.3 KiB
Plaintext
89 lines
3.3 KiB
Plaintext
/****************************************************************************
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**
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** Copyright (C) 2016 The Qt Company Ltd.
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** Contact: https://www.qt.io/licensing/
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**
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** This file is part of the documentation of the Qt Toolkit.
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**
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** $QT_BEGIN_LICENSE:FDL$
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** Commercial License Usage
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** Licensees holding valid commercial Qt licenses may use this file in
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** accordance with the commercial license agreement provided with the
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** Software or, alternatively, in accordance with the terms contained in
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** a written agreement between you and The Qt Company. For licensing terms
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** and conditions see https://www.qt.io/terms-conditions. For further
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** information use the contact form at https://www.qt.io/contact-us.
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**
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** GNU Free Documentation License Usage
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** Alternatively, this file may be used under the terms of the GNU Free
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** Documentation License version 1.3 as published by the Free Software
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** Foundation and appearing in the file included in the packaging of
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** this file. Please review the following information to ensure
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** the GNU Free Documentation License version 1.3 requirements
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** will be met: https://www.gnu.org/licenses/fdl-1.3.html.
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** $QT_END_LICENSE$
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**
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****************************************************************************/
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/*!
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\example statemachine/factorial
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\title Factorial States Example
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\brief The Factorial States example shows how to use \l{The State Machine
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Framework} to calculate the factorial of an integer.
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The statechart for calculating the factorial looks as follows:
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\image factorial-example.png
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\omit
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\caption This is a caption
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\endomit
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In other words, the state machine calculates the factorial of 6 and prints
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the result.
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\snippet statemachine/factorial/main.cpp 0
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The Factorial class is used to hold the data of the computation, \c x and
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\c fac. It also provides a signal that's emitted whenever the value of \c
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x changes.
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\snippet statemachine/factorial/main.cpp 1
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The FactorialLoopTransition class implements the guard (\c x > 1) and
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calculations (\c fac = \c x * \c fac; \c x = \c x - 1) of the factorial
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loop.
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\snippet statemachine/factorial/main.cpp 2
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The FactorialDoneTransition class implements the guard (\c x <= 1) that
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terminates the factorial computation. It also prints the final result to
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standard output.
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\snippet statemachine/factorial/main.cpp 3
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The application's main() function first creates the application object, a
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Factorial object and a state machine.
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\snippet statemachine/factorial/main.cpp 4
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The \c compute state is created, and the initial values of \c x and \c fac
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are defined. A FactorialLoopTransition object is created and added to the
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state.
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\snippet statemachine/factorial/main.cpp 5
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A final state, \c done, is created, and a FactorialDoneTransition object
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is created with \c done as its target state. The transition is then added
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to the \c compute state.
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\snippet statemachine/factorial/main.cpp 6
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The machine's initial state is set to be the \c compute state. We connect
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the QStateMachine::finished() signal to the QCoreApplication::quit() slot,
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so the application will quit when the state machine's work is
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done. Finally, the state machine is started, and the application's event
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loop is entered.
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*/
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