Contents

• Properties
• Public Functions
• Reimplemented Protected Functions
• Detailed Description

Detailed Description

TheQSignalTransition class provides a transition based on a Qt signal.

Typically you would use the overload ofQState::addTransition() that takes a sender and signal as arguments, rather than creatingQSignalTransition objects directly.QSignalTransition is part ofThe State Machine Framework.

You can subclassQSignalTransition and reimplementeventTest() to make a signal transition conditional; the event object passed toeventTest() will be aQStateMachine::SignalEvent object. Example:

class CheckedTransition :publicQSignalTransition{public:    CheckedTransition(QCheckBox*check)        :QSignalTransition(check, SIGNAL(stateChanged(int))) {}protected:    bool eventTest(QEvent*e) {if (!QSignalTransition::eventTest(e))returnfalse;QStateMachine::SignalEvent*se=static_cast<QStateMachine::SignalEvent*>(e);return (se->arguments().at(0).toInt()==Qt::Checked);    }};...QCheckBox*check=newQCheckBox();check->setTristate(true);QState*s1=newQState();QState*s2=newQState();CheckedTransition*t1=new CheckedTransition(check);t1->setTargetState(s2);s1->addTransition(t1);

Property Documentation

senderObject :QObject *

This property holds the sender object that this signal transition is associated with.

Access functions:

signal :QByteArray

This property holds the signal that this signal transition is associated with.

Access functions:

Member Function Documentation

QSignalTransition::QSignalTransition(QState * sourceState = 0)

Constructs a new signal transition with the givensourceState.

QSignalTransition::QSignalTransition(QObject * sender, constchar * signal,QState * sourceState = 0)

Constructs a new signal transition associated with the givensignal of the givensender, and with the givensourceState.

QSignalTransition::~QSignalTransition()

Destroys this signal transition.

[virtual protected]bool QSignalTransition::event(QEvent * e)

Reimplemented fromQObject::event().

[virtual protected]bool QSignalTransition::eventTest(QEvent * event)

Reimplemented fromQAbstractTransition::eventTest().

The default implementation returns true if theevent is aQStateMachine::SignalEvent object and the event's sender and signal index match this transition, and returns false otherwise.

[virtual protected]void QSignalTransition::onTransition(QEvent * event)

Reimplemented fromQAbstractTransition::onTransition().