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+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qhistorystate.h"
+
+#ifndef QT_NO_STATEMACHINE
+
+#include "qhistorystate_p.h"
+
+QT_BEGIN_NAMESPACE
+
+/*!
+ \class QHistoryState
+
+ \brief The QHistoryState class provides a means of returning to a previously active substate.
+
+ \since 4.6
+ \ingroup statemachine
+
+ A history state is a pseudo-state that represents the child state that the
+ parent state was in the last time the parent state was exited. A transition
+ with a history state as its target is in fact a transition to one of the
+ other child states of the parent state. QHistoryState is part of \l{The
+ State Machine Framework}.
+
+ Use the setDefaultState() function to set the state that should be entered
+ if the parent state has never been entered. Example:
+
+ \code
+ QStateMachine machine;
+
+ QState *s1 = new QState();
+ QState *s11 = new QState(s1);
+ QState *s12 = new QState(s1);
+
+ QHistoryState *s1h = new QHistoryState(s1);
+ s1h->setDefaultState(s11);
+
+ machine.addState(s1);
+
+ QState *s2 = new QState();
+ machine.addState(s2);
+
+ QPushButton *button = new QPushButton();
+ // Clicking the button will cause the state machine to enter the child state
+ // that s1 was in the last time s1 was exited, or the history state's default
+ // state if s1 has never been entered.
+ s1->addTransition(button, SIGNAL(clicked()), s1h);
+ \endcode
+
+ By default a history state is shallow, meaning that it won't remember nested
+ states. This can be configured through the historyType property.
+*/
+
+/*!
+ \property QHistoryState::defaultState
+
+ \brief the default state of this history state
+*/
+
+/*!
+ \property QHistoryState::historyType
+
+ \brief the type of history that this history state records
+
+ The default value of this property is QHistoryState::ShallowHistory.
+*/
+
+/*!
+ \enum QHistoryState::HistoryType
+
+ This enum specifies the type of history that a QHistoryState records.
+
+ \value ShallowHistory Only the immediate child states of the parent state
+ are recorded. In this case a transition with the history state as its
+ target will end up in the immediate child state that the parent was in the
+ last time it was exited. This is the default.
+
+ \value DeepHistory Nested states are recorded. In this case a transition
+ with the history state as its target will end up in the most deeply nested
+ descendant state the parent was in the last time it was exited.
+*/
+
+QHistoryStatePrivate::QHistoryStatePrivate()
+ : QAbstractStatePrivate(HistoryState),
+ defaultState(0), historyType(QHistoryState::ShallowHistory)
+{
+}
+
+QHistoryStatePrivate *QHistoryStatePrivate::get(QHistoryState *q)
+{
+ return q->d_func();
+}
+
+/*!
+ Constructs a new shallow history state with the given \a parent state.
+*/
+QHistoryState::QHistoryState(QState *parent)
+ : QAbstractState(*new QHistoryStatePrivate, parent)
+{
+}
+/*!
+ Constructs a new history state of the given \a type, with the given \a
+ parent state.
+*/
+QHistoryState::QHistoryState(HistoryType type, QState *parent)
+ : QAbstractState(*new QHistoryStatePrivate, parent)
+{
+ Q_D(QHistoryState);
+ d->historyType = type;
+}
+
+/*!
+ Destroys this history state.
+*/
+QHistoryState::~QHistoryState()
+{
+}
+
+/*!
+ Returns this history state's default state. The default state indicates the
+ state to transition to if the parent state has never been entered before.
+*/
+QAbstractState *QHistoryState::defaultState() const
+{
+ Q_D(const QHistoryState);
+ return d->defaultState;
+}
+
+/*!
+ Sets this history state's default state to be the given \a state.
+ \a state must be a sibling of this history state.
+
+ Note that this function does not set \a state as the initial state
+ of its parent.
+*/
+void QHistoryState::setDefaultState(QAbstractState *state)
+{
+ Q_D(QHistoryState);
+ if (state && state->parentState() != parentState()) {
+ qWarning("QHistoryState::setDefaultState: state %p does not belong "
+ "to this history state's group (%p)", state, parentState());
+ return;
+ }
+ d->defaultState = state;
+}
+
+/*!
+ Returns the type of history that this history state records.
+*/
+QHistoryState::HistoryType QHistoryState::historyType() const
+{
+ Q_D(const QHistoryState);
+ return d->historyType;
+}
+
+/*!
+ Sets the \a type of history that this history state records.
+*/
+void QHistoryState::setHistoryType(HistoryType type)
+{
+ Q_D(QHistoryState);
+ d->historyType = type;
+}
+
+/*!
+ \reimp
+*/
+void QHistoryState::onEntry(QEvent *event)
+{
+ Q_UNUSED(event);
+}
+
+/*!
+ \reimp
+*/
+void QHistoryState::onExit(QEvent *event)
+{
+ Q_UNUSED(event);
+}
+
+/*!
+ \reimp
+*/
+bool QHistoryState::event(QEvent *e)
+{
+ return QAbstractState::event(e);
+}
+
+QT_END_NAMESPACE
+
+#endif //QT_NO_STATEMACHINE