注意
该类在 Qt4.6 引入
PySide.QtCore.QSignalTransition class provides a transition based on a Qt signal.
Typically you would use the overload of QState.addTransition() that takes a sender and signal as arguments, rather than creating PySide.QtCore.QSignalTransition objects directly. PySide.QtCore.QSignalTransition is part of 状态机框架 .
You can subclass PySide.QtCore.QSignalTransition and reimplement PySide.QtCore.QSignalTransition.eventTest() to make a signal transition conditional; the event object passed to PySide.QtCore.QSignalTransition.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);
| 参数： |
|
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Constructs a new signal transition associated with the given signal 为给定 sender ，和采用给定 sourceState .
Constructs a new signal transition with the given sourceState .
| 返回类型： | PySide.QtCore.QObject |
|---|
This property holds the sender object that this signal transition is associated with.
| 参数： | sender – PySide.QtCore.QObject |
|---|
This property holds the sender object that this signal transition is associated with.
| 参数： | signal – PySide.QtCore.QByteArray |
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This property holds the signal that this signal transition is associated with.
| 返回类型： | PySide.QtCore.QByteArray |
|---|
This property holds the signal that this signal transition is associated with.