transitions.hpp Example File

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    #ifndef TRANSITIONS_HPP
    #define TRANSITIONS_HPP

    #include <QtCore/QSignalTransition>

    class Factorial;
    class QEvent;

    /**
     * This custom transition has the 'compute' state as source and
     * target state, so it just loops until eventTest() returns 'false'.
     * Inside the onTransition() method the actual work (calculating the factorial)
     * is done.
     */
    class FactorialLoopTransition : public QSignalTransition
    {
    public:
        // Creates a new factorial loop transition that works on the values of the given Factorial object
        FactorialLoopTransition(Factorial *fact);

        // This method is called by the state machine to check whether this transition can be executed
        virtual bool eventTest(QEvent *e);

        // This method is called by the state machine if this transition is executed
        virtual void onTransition(QEvent *e);

    private:
        // The Factorial object to work on
        Factorial *m_fact;
    };

    /**
     * This custom transition has the 'compute' state as source and
     * the 'done' state as target state.
     * It tests inside eventTest() whether the calculation of the factorial is finished
     * and returns 'true' in this case.
     */
    class FactorialDoneTransition : public QSignalTransition
    {
    public:
        // Creates a new factorial loop transition that works on the values of the given Factorial object
        FactorialDoneTransition(Factorial *fact);

        // This method is called by the state machine to check whether this transition can be executed
        virtual bool eventTest(QEvent *e);

    private:
        // The Factorial object to work on
        Factorial *m_fact;
    };

    #endif