The QSignalTransition class provides a transition based on a Qt signal. More...
Header: | #include <QSignalTransition> |
CMake: | find_package(Qt6 COMPONENTS StateMachine REQUIRED) target_link_libraries(mytarget PRIVATE Qt6::StateMachine) |
qmake: | QT += statemachine |
Inherits: | QAbstractTransition |
QSignalTransition(const QObject *sender, PointerToMemberFunction signal, QState *sourceState = nullptr) | |
QSignalTransition(const QObject *sender, const char *signal, QState *sourceState = nullptr) | |
QSignalTransition(QState *sourceState = nullptr) | |
virtual | ~QSignalTransition() |
const QObject * | senderObject() const |
void | setSenderObject(const QObject *sender) |
void | setSignal(const QByteArray &signal) |
QByteArray | signal() const |
void | senderObjectChanged() |
void | signalChanged() |
virtual bool | event(QEvent *e) override |
virtual bool | eventTest(QEvent *event) override |
virtual void | onTransition(QEvent *event) override |
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 Qt 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:
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);
[bindable]
senderObject : const QObject*
Note: This property supports QProperty bindings.
This property holds the sender object that this signal transition is associated with
[bindable]
signal : QByteArray
Note: This property supports QProperty bindings.
This property holds the signal that this signal transition is associated with
[since 5.7]
template <typename PointerToMemberFunction> QSignalTransition::QSignalTransition(const QObject *sender, PointerToMemberFunction signal, QState *sourceState = nullptr)
This is an overloaded function.
Constructs a new signal transition associated with the given signal of the given sender object and with the given sourceState. This constructor is enabled if the compiler supports delegating constructors, as indicated by the presence of the macro Q_COMPILER_DELEGATING_CONSTRUCTORS.
This function was introduced in Qt 5.7.
Constructs a new signal transition associated with the given signal of the given sender, and with the given sourceState.
Constructs a new signal transition with the given sourceState.
[private signal, since 5.4]
void QSignalTransition::senderObjectChanged()
This signal is emitted when the senderObject property is changed.
Note: This is a private signal. It can be used in signal connections but cannot be emitted by the user.
Note: Notifier signal for property senderObject.
This function was introduced in Qt 5.4.
See also QSignalTransition::senderObject.
[private signal, since 5.4]
void QSignalTransition::signalChanged()
This signal is emitted when the signal property is changed.
Note: This is a private signal. It can be used in signal connections but cannot be emitted by the user.
Note: Notifier signal for property signal.
This function was introduced in Qt 5.4.
See also QSignalTransition::signal.
[virtual]
QSignalTransition::~QSignalTransition()
Destroys this signal transition.
[override virtual protected]
bool QSignalTransition::event(QEvent *e)
Reimplements: QAbstractTransition::event(QEvent *e).
[override virtual protected]
bool QSignalTransition::eventTest(QEvent *event)
Reimplements: QAbstractTransition::eventTest(QEvent *event).
The default implementation returns true
if the event is a QStateMachine::SignalEvent object and the event's sender and signal index match this transition, and returns false
otherwise.
[override virtual protected]
void QSignalTransition::onTransition(QEvent *event)
Reimplements: QAbstractTransition::onTransition(QEvent *event).
Returns the sender object associated with this signal transition.
Note: Getter function for property senderObject.
See also setSenderObject().
Sets the sender object associated with this signal transition.
Note: Setter function for property senderObject.
See also senderObject().
Sets the signal associated with this signal transition.
Note: Setter function for property signal.
See also signal().
Returns the signal associated with this signal transition.
Note: Getter function for property signal.
See also setSignal().
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Licensed under the GNU Free Documentation License, Version 1.3.
https://doc.qt.io/qt-6.2/qsignaltransition.html