source: trunk/src/corelib/statemachine/qabstractstate.cpp@ 813

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#include "qabstractstate.h"

#ifndef QT_NO_STATEMACHINE

#include "qabstractstate_p.h"
#include "qstate.h"
#include "qstate_p.h"
#include "qstatemachine.h"
#include "qstatemachine_p.h"

QT_BEGIN_NAMESPACE

/*!
  \class QAbstractState

  \brief The QAbstractState class is the base class of states of a QStateMachine.

  \since 4.6
  \ingroup statemachine

  The QAbstractState class is the abstract base class of states that are part
  of a QStateMachine. It defines the interface that all state objects have in
  common. QAbstractState is part of \l{The State Machine Framework}.

  The entered() signal is emitted when the state has been entered. The
  exited() signal is emitted when the state has been exited.

  The parentState() function returns the state's parent state. The machine()
  function returns the state machine that the state is part of.

  \section1 Subclassing

  The onEntry() function is called when the state is entered; reimplement this
  function to perform custom processing when the state is entered.

  The onExit() function is called when the state is exited; reimplement this
  function to perform custom processing when the state is exited.
*/

QAbstractStatePrivate::QAbstractStatePrivate(StateType type)
    : stateType(type), isMachine(false), parentState(0)
{
}

QAbstractStatePrivate *QAbstractStatePrivate::get(QAbstractState *q)
{
    return q->d_func();
}

const QAbstractStatePrivate *QAbstractStatePrivate::get(const QAbstractState *q)
{
    return q->d_func();
}

QStateMachine *QAbstractStatePrivate::machine() const
{
    QObject *par = parent;
    while (par != 0) {
        if (QStateMachine *mach = qobject_cast<QStateMachine*>(par))
            return mach;
        par = par->parent();
    }
    return 0;
}

void QAbstractStatePrivate::callOnEntry(QEvent *e)
{
    Q_Q(QAbstractState);
    q->onEntry(e);
}

void QAbstractStatePrivate::callOnExit(QEvent *e)
{
    Q_Q(QAbstractState);
    q->onExit(e);
}

void QAbstractStatePrivate::emitEntered()
{
    Q_Q(QAbstractState);
    emit q->entered();
}

void QAbstractStatePrivate::emitExited()
{
    Q_Q(QAbstractState);
    emit q->exited();
}

/*!
  Constructs a new state with the given \a parent state.
*/
QAbstractState::QAbstractState(QState *parent)
    : QObject(*new QAbstractStatePrivate(QAbstractStatePrivate::AbstractState), parent)
{
}

/*!
  \internal
*/
QAbstractState::QAbstractState(QAbstractStatePrivate &dd, QState *parent)
    : QObject(dd, parent)
{
}

/*!
  Destroys this state.
*/
QAbstractState::~QAbstractState()
{
}

/*!
  Returns this state's parent state, or 0 if the state has no parent state.
*/
QState *QAbstractState::parentState() const
{
    Q_D(const QAbstractState);
    if (d->parentState != parent())
        d->parentState = qobject_cast<QState*>(parent());
    return d->parentState;
}

/*!
  Returns the state machine that this state is part of, or 0 if the state is
  not part of a state machine.
*/
QStateMachine *QAbstractState::machine() const
{
    Q_D(const QAbstractState);
    return d->machine();
}

/*!
  \fn QAbstractState::onExit(QEvent *event)

  This function is called when the state is exited. The given \a event is what
  caused the state to be exited. Reimplement this function to perform custom
  processing when the state is exited.
*/

/*!
  \fn QAbstractState::onEntry(QEvent *event)

  This function is called when the state is entered. The given \a event is
  what caused the state to be entered. Reimplement this function to perform
  custom processing when the state is entered.
*/

/*!
  \fn QAbstractState::entered()

  This signal is emitted when the state has been entered (after onEntry() has
  been called).
*/

/*!
  \fn QAbstractState::exited()

  This signal is emitted when the state has been exited (after onExit() has
  been called).
*/

/*!
  \reimp
*/
bool QAbstractState::event(QEvent *e)
{
    return QObject::event(e);
}

QT_END_NAMESPACE

#endif //QT_NO_STATEMACHINE