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# main.cpp Example File

statemachine/eventtransitions/main.cpp

     /****************************************************************************
     **
     ** Copyright (C) 2015 The Qt Company Ltd.
     ** Contact: http://www.qt.io/licensing/
     **
     ** This file is part of the QtCore module of the Qt Toolkit.
     **
     ** $QT_BEGIN_LICENSE:BSD$
     ** You may use this file under the terms of the BSD license as follows:
     **
     ** "Redistribution and use in source and binary forms, with or without
     ** modification, are permitted provided that the following conditions are
     ** met:
     **   * Redistributions of source code must retain the above copyright
     **     notice, this list of conditions and the following disclaimer.
     **   * Redistributions in binary form must reproduce the above copyright
     **     notice, this list of conditions and the following disclaimer in
     **     the documentation and/or other materials provided with the
     **     distribution.
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     **     contributors may be used to endorse or promote products derived
     **     from this software without specific prior written permission.
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     **
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     ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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     #include <QtGui>

     class Window : public QWidget
     {
     public:
         Window(QWidget *parent = 0)
             : QWidget(parent)
         {
             QPushButton *button = new QPushButton(this);
             button->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);

             QVBoxLayout *layout = new QVBoxLayout;
             layout->addWidget(button);
             layout->setContentsMargins(80, 80, 80, 80);
             setLayout(layout);

             QStateMachine *machine = new QStateMachine(this);

             QState *s1 = new QState();
             s1->assignProperty(button, "text", "Outside");

             QState *s2 = new QState();
             s2->assignProperty(button, "text", "Inside");

             QEventTransition *enterTransition = new QEventTransition(button, QEvent::Enter);
             enterTransition->setTargetState(s2);
             s1->addTransition(enterTransition);

             QEventTransition *leaveTransition = new QEventTransition(button, QEvent::Leave);
             leaveTransition->setTargetState(s1);
             s2->addTransition(leaveTransition);

             QState *s3 = new QState();
             s3->assignProperty(button, "text", "Pressing...");

             QEventTransition *pressTransition = new QEventTransition(button, QEvent::MouseButtonPress);
             pressTransition->setTargetState(s3);
             s2->addTransition(pressTransition);

             QEventTransition *releaseTransition = new QEventTransition(button, QEvent::MouseButtonRelease);
             releaseTransition->setTargetState(s2);
             s3->addTransition(releaseTransition);

             machine->addState(s1);
             machine->addState(s2);
             machine->addState(s3);

             machine->setInitialState(s1);
             machine->start();
         }
     };

     int main(int argc, char **argv)
     {
         QApplication app(argc, argv);
         Window window;
         window.resize(300, 300);
     #if defined(Q_OS_SYMBIAN)
         window.showMaximized();
     #else
         window.show();
     #endif

         return app.exec();
     }