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#include "qeventtransition.h"

#ifndef QT_NO_STATEMACHINE

#include "qeventtransition_p.h"

#include "qstate.h"

#include "qstate_p.h"

#include "qstatemachine.h"

#include "qstatemachine_p.h"

#include <qdebug.h>

QT_BEGIN_NAMESPACE

/*!

  \class QEventTransition

  \brief The QEventTransition class provides a QObject-specific transition for Qt events.

  \since 4.6

  \ingroup statemachine

  A QEventTransition object binds an event to a particular QObject.

  QEventTransition is part of \l{The State Machine Framework}.

  Example:

  \code

  QPushButton *button = ...;

  QState *s1 = ...;

  QState *s2 = ...;

  // If in s1 and the button receives an Enter event, transition to s2

  QEventTransition *enterTransition = new QEventTransition(button, QEvent::Enter);

  enterTransition->setTargetState(s2);

  s1->addTransition(enterTransition);

  // If in s2 and the button receives an Exit event, transition back to s1

  QEventTransition *leaveTransition = new QEventTransition(button, QEvent::Leave);

  leaveTransition->setTargetState(s1);

  s2->addTransition(leaveTransition);

  \endcode

  \section1 Subclassing

  When reimplementing the eventTest() function, you should first call the base

  implementation to verify that the event is a QStateMachine::WrappedEvent for

  the proper object and event type. You may then cast the event to a

  QStateMachine::WrappedEvent and get the original event by calling

  QStateMachine::WrappedEvent::event(), and perform additional checks on that

  object.

  \sa QState::addTransition()

*/

/*!

    \property QEventTransition::eventSource

    \brief the event source that this event transition is associated with

*/

/*!

    \property QEventTransition::eventType

    \brief the type of event that this event transition is associated with

*/

QEventTransitionPrivate::QEventTransitionPrivate()

{

    object = 0;

    eventType = QEvent::None;

    registered = false;

}

QEventTransitionPrivate *QEventTransitionPrivate::get(QEventTransition *q)

{

    return q->d_func();

}

void QEventTransitionPrivate::unregister()

{

    Q_Q(QEventTransition);

    if (!registered || !machine())

        return;

    QStateMachinePrivate::get(machine())->unregisterEventTransition(q);

}

void QEventTransitionPrivate::maybeRegister()

{

    Q_Q(QEventTransition);

    if (!machine() || !machine()->configuration().contains(sourceState()))

        return;

    QStateMachinePrivate::get(machine())->registerEventTransition(q);

}

/*!

  Constructs a new QEventTransition object with the given \a sourceState.

*/

QEventTransition::QEventTransition(QState *sourceState)

    : QAbstractTransition(*new QEventTransitionPrivate, sourceState)

{

}

/*!

  Constructs a new QEventTransition object associated with events of the given

  \a type for the given \a object, and with the given \a sourceState.

*/

QEventTransition::QEventTransition(QObject *object, QEvent::Type type,

                                   QState *sourceState)

    : QAbstractTransition(*new QEventTransitionPrivate, sourceState)

{

    Q_D(QEventTransition);

    d->registered = false;

    d->object = object;

    d->eventType = type;

}

/*!

  \internal

*/

QEventTransition::QEventTransition(QEventTransitionPrivate &dd, QState *parent)

    : QAbstractTransition(dd, parent)

{

}

/*!

  \internal

*/

QEventTransition::QEventTransition(QEventTransitionPrivate &dd, QObject *object,

                                   QEvent::Type type, QState *parent)

    : QAbstractTransition(dd, parent)

{

    Q_D(QEventTransition);

    d->registered = false;

    d->object = object;

    d->eventType = type;

}

/*!

  Destroys this QObject event transition.

*/

QEventTransition::~QEventTransition()

{

}

/*!

  Returns the event type that this event transition is associated with.

*/

QEvent::Type QEventTransition::eventType() const

{

    Q_D(const QEventTransition);

    return d->eventType;

}

/*!

  Sets the event \a type that this event transition is associated with.

*/

void QEventTransition::setEventType(QEvent::Type type)

{

    Q_D(QEventTransition);

    if (d->eventType == type)

        return;

    d->unregister();

    d->eventType = type;

    d->maybeRegister();

}

/*!

  Returns the event source associated with this event transition.

*/

QObject *QEventTransition::eventSource() const

{

    Q_D(const QEventTransition);

    return d->object;

}

/*!

  Sets the event source associated with this event transition to be the given

  \a object.

*/

void QEventTransition::setEventSource(QObject *object)

{

    Q_D(QEventTransition);

    if (d->object == object)

        return;

    d->unregister();

    d->object = object;

    d->maybeRegister();

}

/*!

  \reimp

*/

bool QEventTransition::eventTest(QEvent *event)

{

    Q_D(const QEventTransition);

    if (event->type() == QEvent::StateMachineWrapped) {

        QStateMachine::WrappedEvent *we = static_cast<QStateMachine::WrappedEvent*>(event);

        return (we->object() == d->object)

            && (we->event()->type() == d->eventType);

    }

    return false;

}

/*!

  \reimp

*/

void QEventTransition::onTransition(QEvent *event)

{

    Q_UNUSED(event);

}

/*!

  \reimp

*/

bool QEventTransition::event(QEvent *e)

{

    return QAbstractTransition::event(e);

}

QT_END_NAMESPACE

#endif //QT_NO_STATEMACHINE