source: trunk/src/corelib/statemachine/qsignaltransition.cpp@ 890

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#include "qsignaltransition.h"

#ifndef QT_NO_STATEMACHINE

#include "qsignaltransition_p.h"
#include "qstate.h"
#include "qstate_p.h"
#include "qstatemachine.h"
#include "qstatemachine_p.h"
#include <qdebug.h>

QT_BEGIN_NAMESPACE

/*!
  \class QSignalTransition

  \brief The QSignalTransition class provides a transition based on a Qt signal.

  \since 4.6
  \ingroup statemachine

  Typically you would use the overload of QState::addTransition() that takes a
  sender and signal as arguments, rather than creating QSignalTransition
  objects directly. QSignalTransition is part of \l{The State Machine
  Framework}.

  You can subclass QSignalTransition and reimplement eventTest() to make a
  signal transition conditional; the event object passed to eventTest() will
  be a QStateMachine::SignalEvent object. Example:

  \code
  class CheckedTransition : public QSignalTransition
  {
  public:
      CheckedTransition(QCheckBox *check)
          : QSignalTransition(check, SIGNAL(stateChanged(int))) {}
  protected:
      bool eventTest(QEvent *e) {
          if (!QSignalTransition::eventTest(e))
              return false;
          QStateMachine::SignalEvent *se = static_cast<QStateMachine::SignalEvent*>(e);
          return (se->arguments().at(0).toInt() == Qt::Checked);
      }
  };

  ...

  QCheckBox *check = new QCheckBox();
  check->setTristate(true);

  QState *s1 = new QState();
  QState *s2 = new QState();
  CheckedTransition *t1 = new CheckedTransition(check);
  t1->setTargetState(s2);
  s1->addTransition(t1);
  \endcode
*/

/*!
    \property QSignalTransition::senderObject

    \brief the sender object that this signal transition is associated with
*/

/*!
    \property QSignalTransition::signal

    \brief the signal that this signal transition is associated with
*/

QSignalTransitionPrivate::QSignalTransitionPrivate()
{
    sender = 0;
    signalIndex = -1;
}

QSignalTransitionPrivate *QSignalTransitionPrivate::get(QSignalTransition *q)
{
    return q->d_func();
}

void QSignalTransitionPrivate::unregister()
{
    Q_Q(QSignalTransition);
    if ((signalIndex == -1) || !machine())
        return;
    QStateMachinePrivate::get(machine())->unregisterSignalTransition(q);
}

void QSignalTransitionPrivate::maybeRegister()
{