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</style></head><body><table border="0" cellpadding="0" cellspacing="0" width="100%"><tr /><td align="left" valign="top" width="32"><img align="left" border="0" height="32" src="images/rb-logo.png" width="32" /></td><td width="1">  </td><td class="postheader" valign="center"><a href="../pyqt4ref.html"><font color="#004faf">Home</font></a> · <a href="classes.html"><font color="#004faf">All Classes</font></a> · <a href="modules.html"><font color="#004faf">Modules</font></a></td></table><h1 align="center">QSignalTransition Class Reference<br /><sup><sup>[<a href="qtcore.html">QtCore</a> module]</sup></sup></h1><p>The QSignalTransition class provides a transition based on a Qt
signal. <a href="#details">More...</a></p>
<p>Inherits <a href="qabstracttransition.html">QAbstractTransition</a>.</p><h3>Methods</h3><ul><li><div class="fn" /><b><a href="qsignaltransition.html#QSignalTransition">__init__</a></b> (<i>self</i>, QState <i>sourceState</i> = None)</li><li><div class="fn" /><b><a href="qsignaltransition.html#QSignalTransition-2">__init__</a></b> (<i>self</i>, QObject <i>sender</i>, SIGNAL() <i>signal</i>, QState <i>sourceState</i> = None)</li><li><div class="fn" /><b><a href="qsignaltransition.html#QSignalTransition-3">__init__</a></b> (<i>self</i>, signal <i>signal</i>, QState <i>sourceState</i> = None)</li><li><div class="fn" />bool <b><a href="qsignaltransition.html#event">event</a></b> (<i>self</i>, QEvent <i>e</i>)</li><li><div class="fn" />bool <b><a href="qsignaltransition.html#eventTest">eventTest</a></b> (<i>self</i>, QEvent <i>event</i>)</li><li><div class="fn" /><b><a href="qsignaltransition.html#onTransition">onTransition</a></b> (<i>self</i>, QEvent <i>event</i>)</li><li><div class="fn" />QObject <b><a href="qsignaltransition.html#senderObject">senderObject</a></b> (<i>self</i>)</li><li><div class="fn" /><b><a href="qsignaltransition.html#setSenderObject">setSenderObject</a></b> (<i>self</i>, QObject <i>sender</i>)</li><li><div class="fn" /><b><a href="qsignaltransition.html#setSignal">setSignal</a></b> (<i>self</i>, QByteArray <i>signal</i>)</li><li><div class="fn" />QByteArray <b><a href="qsignaltransition.html#signal">signal</a></b> (<i>self</i>)</li></ul><a name="details" /><hr /><h2>Detailed Description</h2><p>The QSignalTransition class provides a transition based on a Qt
signal.</p>
<p>Typically you would use the overload of <a href="qstate.html#addTransition">QState.addTransition</a>() that takes
a sender and signal as arguments, rather than creating
QSignalTransition objects directly. QSignalTransition is part of
<a href="statemachine-api.html">The State Machine
Framework</a>.</p>
<p>You can subclass QSignalTransition and reimplement <a href="qsignaltransition.html#eventTest">eventTest</a>() to make a signal
transition conditional; the event object passed to <a href="qsignaltransition.html#eventTest">eventTest</a>() will be a
<a href="qstatemachine-signalevent.html">QStateMachine.SignalEvent</a>
object. Example:</p>
<pre class="highlightedCode brush: cpp">
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);
</pre><hr /><h2>Method Documentation</h2><h3 class="fn"><a name="QSignalTransition" />QSignalTransition.__init__ (<i>self</i>, <a href="qstate.html">QState</a> <i>sourceState</i> = None)</h3><p>Constructs a new signal transition with the given
<i>sourceState</i>.</p>
<h3 class="fn"><a name="QSignalTransition-2" />QSignalTransition.__init__ (<i>self</i>, <a href="qobject.html">QObject</a> <i>sender</i>, SIGNAL() <i>signal</i>, <a href="qstate.html">QState</a> <i>sourceState</i> = None)</h3><p>Constructs a new signal transition associated with the given
<i>signal</i> of the given <i>sender</i>, and with the given
<i>sourceState</i>.</p>
<h3 class="fn"><a name="QSignalTransition-3" />QSignalTransition.__init__ (<i>self</i>, signal <i>signal</i>, <a href="qstate.html">QState</a> <i>sourceState</i> = None)</h3><h3 class="fn"><a name="event" />bool QSignalTransition.event (<i>self</i>, <a href="qevent.html">QEvent</a> <i>e</i>)</h3><p>Reimplemented from <a href="qobject.html#event">QObject.event</a>().</p>
<h3 class="fn"><a name="eventTest" />bool QSignalTransition.eventTest (<i>self</i>, <a href="qevent.html">QEvent</a> <i>event</i>)</h3><p>Reimplemented from <a href="qabstracttransition.html#eventTest">QAbstractTransition.eventTest</a>().</p>
<p>The default implementation returns true if the <i>event</i> is a
<a href="qstatemachine-signalevent.html">QStateMachine.SignalEvent</a>
object and the event's sender and signal index match this
transition, and returns false otherwise.</p>
<h3 class="fn"><a name="onTransition" />QSignalTransition.onTransition (<i>self</i>, <a href="qevent.html">QEvent</a> <i>event</i>)</h3><p>Reimplemented from <a href="qabstracttransition.html#onTransition">QAbstractTransition.onTransition</a>().</p>
<h3 class="fn"><a name="senderObject" /><a href="qobject.html">QObject</a> QSignalTransition.senderObject (<i>self</i>)</h3><h3 class="fn"><a name="setSenderObject" />QSignalTransition.setSenderObject (<i>self</i>, <a href="qobject.html">QObject</a> <i>sender</i>)</h3><h3 class="fn"><a name="setSignal" />QSignalTransition.setSignal (<i>self</i>, <a href="qbytearray.html">QByteArray</a> <i>signal</i>)</h3><h3 class="fn"><a name="signal" /><a href="qbytearray.html">QByteArray</a> QSignalTransition.signal (<i>self</i>)</h3><address><hr /><div align="center"><table border="0" cellspacing="0" width="100%"><tr class="address"><td align="left" width="25%">PyQt 4.8.3 for X11</td><td align="center" width="50%">Copyright © <a href="http://www.riverbankcomputing.com">Riverbank Computing Ltd</a> and <a href="http://www.qtsoftware.com">Nokia</a> 2011</td><td align="right" width="25%">Qt 4.7.1</td></tr></table></div></address></body></html>
