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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
// Qt-Security score:significant
#include "qeventtransition.h"
#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
\inmodule QtStateMachine
\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{Qt State Machine Overview}{Qt 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()
{
}
void QEventTransitionPrivate::unregister()
{
Q_Q(QEventTransition);
if (!registered || !machine())
return;
QStateMachinePrivate::get(machine())->unregisterEventTransition(q);
}
void QEventTransitionPrivate::maybeRegister()
{
Q_Q(QEventTransition);
if (QStateMachine *mach = machine())
QStateMachinePrivate::get(mach)->maybeRegisterEventTransition(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.setValueBypassingBindings(object);
d->eventType.setValueBypassingBindings(type);
d->maybeRegister();
}
/*!
\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.setValueBypassingBindings(object);
d->eventType.setValueBypassingBindings(type);
d->maybeRegister();
}
/*!
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);
d->eventType.removeBindingUnlessInWrapper();
if (d->eventType.valueBypassingBindings() == type)
return;
d->unregister();
d->eventType.setValueBypassingBindings(type);
d->maybeRegister();
d->eventType.notify();
}
QBindable<QEvent::Type> QEventTransition::bindableEventType()
{
Q_D(QEventTransition);
return &d->eventType;
}
/*!
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);
d->object.removeBindingUnlessInWrapper();
if (d->object.valueBypassingBindings() == object)
return;
d->unregister();
d->object.setValueBypassingBindings(object);
d->maybeRegister();
d->object.notify();
}
QBindable<QObject*> QEventTransition::bindableEventSource()
{
Q_D(QEventTransition);
return &d->object;
}
/*!
\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.value());
}
return false;
}
/*!
\reimp
*/
void QEventTransition::onTransition(QEvent *event)
{
Q_UNUSED(event);
}
/*!
\reimp
*/
bool QEventTransition::event(QEvent *e)
{
return QAbstractTransition::event(e);
}
QT_END_NAMESPACE
#include "moc_qeventtransition.cpp"