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<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>QObject Class Reference</h1>
<p>The QObject class is the base class of all Qt objects.
<a href="#details">More...</a>
<p><tt>#include <<a href="qobject-h.html">qobject.h</a>></tt>
<p>Inherits <a href="qt.html">Qt</a>.
<p>Inherited by <a href="qaccel.html">QAccel</a>, <a href="qaccessibleobject.html">QAccessibleObject</a>, <a href="qaction.html">QAction</a>, <a href="qapplication.html">QApplication</a>, <a href="qdatapump.html">QDataPump</a>, <a href="qwidget.html">QWidget</a>, <a href="qcanvas.html">QCanvas</a>, <a href="qstyle.html">QStyle</a>, <a href="qclipboard.html">QClipboard</a>, <a href="qcopchannel.html">QCopChannel</a>, <a href="qdns.html">QDns</a>, <a href="qlayout.html">QLayout</a>, <a href="qdragobject.html">QDragObject</a>, <a href="qeditorfactory.html">QEditorFactory</a>, <a href="qfileiconprovider.html">QFileIconProvider</a>, <a href="qnetworkprotocol.html">QNetworkProtocol</a>, <a href="qserversocket.html">QServerSocket</a>, <a href="qwskeyboardhandler.html">QWSKeyboardHandler</a>, <a href="qnetworkoperation.html">QNetworkOperation</a>, <a href="qnpinstance.html">QNPInstance</a>, <a href="qobjectcleanuphandler.html">QObjectCleanupHandler</a>, <a href="qprocess.html">QProcess</a>, <a href="qsessionmanager.html">QSessionManager</a>, <a href="qsignal.html">QSignal</a>, <a href="qsignalmapper.html">QSignalMapper</a>, <a href="qsocket.html">QSocket</a>, <a href="qsocketnotifier.html">QSocketNotifier</a>, <a href="qsound.html">QSound</a>, <a href="qsqldatabase.html">QSqlDatabase</a>, <a href="qsqldriver.html">QSqlDriver</a>, <a href="qsqlform.html">QSqlForm</a>, <a href="qstylesheet.html">QStyleSheet</a>, <a href="qtimer.html">QTimer</a>, <a href="qtooltipgroup.html">QToolTipGroup</a>, <a href="qtranslator.html">QTranslator</a>, <a href="qurloperator.html">QUrlOperator</a>, <a href="qvalidator.html">QValidator</a> and <a href="qwsmousehandler.html">QWSMouseHandler</a>.
<p><a href="qobject-members.html">List of all member functions.</a>
<h2>Public Members</h2>
<ul>
<li><div class=fn><a href="#QObject"><b>QObject</b></a> ( QObject * parent = 0, const char * name = 0 )</div></li>
<li><div class=fn>virtual <a href="#~QObject"><b>~QObject</b></a> ()</div></li>
<li><div class=fn>const char * <a href="#className"><b>className</b></a> () const</div></li>
<li><div class=fn>QString <a href="#tr"><b>tr</b></a> ( const char * sourceText, const char * comment ) const</div></li>
<li><div class=fn>QString <a href="#trUtf8"><b>trUtf8</b></a> ( const char * sourceText, const char * comment ) const</div></li>
<li><div class=fn>QMetaObject * <a href="#metaObject"><b>metaObject</b></a> () const</div></li>
<li><div class=fn>virtual bool <a href="#event"><b>event</b></a> ( QEvent * e )</div></li>
<li><div class=fn>virtual bool <a href="#eventFilter"><b>eventFilter</b></a> ( QObject * watched, QEvent * e )</div></li>
<li><div class=fn>bool <a href="#isA"><b>isA</b></a> ( const char * clname ) const</div></li>
<li><div class=fn>bool <a href="#inherits"><b>inherits</b></a> ( const char * clname ) const</div></li>
<li><div class=fn>const char * <a href="#name"><b>name</b></a> () const</div></li>
<li><div class=fn>const char * <a href="#name-2"><b>name</b></a> ( const char * defaultName ) const</div></li>
<li><div class=fn>virtual void <a href="#setName"><b>setName</b></a> ( const char * name )</div></li>
<li><div class=fn>bool <a href="#isWidgetType"><b>isWidgetType</b></a> () const</div></li>
<li><div class=fn>bool <a href="#highPriority"><b>highPriority</b></a> () const</div></li>
<li><div class=fn>bool <a href="#signalsBlocked"><b>signalsBlocked</b></a> () const</div></li>
<li><div class=fn>void <a href="#blockSignals"><b>blockSignals</b></a> ( bool block )</div></li>
<li><div class=fn>int <a href="#startTimer"><b>startTimer</b></a> ( int interval )</div></li>
<li><div class=fn>void <a href="#killTimer"><b>killTimer</b></a> ( int id )</div></li>
<li><div class=fn>void <a href="#killTimers"><b>killTimers</b></a> ()</div></li>
<li><div class=fn>QObject * <a href="#child"><b>child</b></a> ( const char * objName, const char * inheritsClass = 0, bool recursiveSearch = TRUE )</div></li>
<li><div class=fn>const QObjectList * <a href="#children"><b>children</b></a> () const</div></li>
<li><div class=fn>QObjectList * <a href="#queryList"><b>queryList</b></a> ( const char * inheritsClass = 0, const char * objName = 0, bool regexpMatch = TRUE, bool recursiveSearch = TRUE ) const</div></li>
<li><div class=fn>virtual void <a href="#insertChild"><b>insertChild</b></a> ( QObject * obj )</div></li>
<li><div class=fn>virtual void <a href="#removeChild"><b>removeChild</b></a> ( QObject * obj )</div></li>
<li><div class=fn>void <a href="#installEventFilter"><b>installEventFilter</b></a> ( const QObject * obj )</div></li>
<li><div class=fn>void <a href="#removeEventFilter"><b>removeEventFilter</b></a> ( const QObject * obj )</div></li>
<li><div class=fn>bool <a href="#connect-2"><b>connect</b></a> ( const QObject * sender, const char * signal, const char * member ) const</div></li>
<li><div class=fn>bool <a href="#disconnect-2"><b>disconnect</b></a> ( const char * signal = 0, const QObject * receiver = 0, const char * member = 0 )</div></li>
<li><div class=fn>bool <a href="#disconnect-3"><b>disconnect</b></a> ( const QObject * receiver, const char * member = 0 )</div></li>
<li><div class=fn>void <a href="#dumpObjectTree"><b>dumpObjectTree</b></a> ()</div></li>
<li><div class=fn>void <a href="#dumpObjectInfo"><b>dumpObjectInfo</b></a> ()</div></li>
<li><div class=fn>virtual bool <a href="#setProperty"><b>setProperty</b></a> ( const char * name, const QVariant & value )</div></li>
<li><div class=fn>virtual QVariant <a href="#property"><b>property</b></a> ( const char * name ) const</div></li>
<li><div class=fn>QObject * <a href="#parent"><b>parent</b></a> () const</div></li>
</ul>
<h2>Public Slots</h2>
<ul>
<li><div class=fn>void <a href="#deleteLater"><b>deleteLater</b></a> ()</div></li>
</ul>
<h2>Signals</h2>
<ul>
<li><div class=fn>void <a href="#destroyed"><b>destroyed</b></a> ()</div></li>
<li><div class=fn>void <a href="#destroyed-2"><b>destroyed</b></a> ( QObject * obj )</div></li>
</ul>
<h2>Static Public Members</h2>
<ul>
<li><div class=fn>const QObjectList * <a href="#objectTrees"><b>objectTrees</b></a> ()</div></li>
<li><div class=fn>bool <a href="#connect"><b>connect</b></a> ( const QObject * sender, const char * signal, const QObject * receiver, const char * member )</div></li>
<li><div class=fn>bool <a href="#disconnect"><b>disconnect</b></a> ( const QObject * sender, const char * signal, const QObject * receiver, const char * member )</div></li>
</ul>
<h2>Properties</h2>
<ul>
<li><div class=fn>QCString <a href="#name-prop"><b>name</b></a> - the name of this object</div></li>
</ul>
<h2>Protected Members</h2>
<ul>
<li><div class=fn>const QObject * <a href="#sender"><b>sender</b></a> ()</div></li>
<li><div class=fn>virtual void <a href="#timerEvent"><b>timerEvent</b></a> ( QTimerEvent * )</div></li>
<li><div class=fn>virtual void <a href="#childEvent"><b>childEvent</b></a> ( QChildEvent * )</div></li>
<li><div class=fn>virtual void <a href="#customEvent"><b>customEvent</b></a> ( QCustomEvent * )</div></li>
<li><div class=fn>virtual void <a href="#connectNotify"><b>connectNotify</b></a> ( const char * signal )</div></li>
<li><div class=fn>virtual void <a href="#disconnectNotify"><b>disconnectNotify</b></a> ( const char * signal )</div></li>
<li><div class=fn>virtual bool <a href="#checkConnectArgs"><b>checkConnectArgs</b></a> ( const char * signal, const QObject * receiver, const char * member )</div></li>
</ul>
<h2>Static Protected Members</h2>
<ul>
<li><div class=fn>QCString <a href="#normalizeSignalSlot"><b>normalizeSignalSlot</b></a> ( const char * signalSlot )</div></li>
</ul>
<h2>Related Functions</h2>
<ul>
<li><div class=fn>void * <a href="#qt_find_obj_child"><b>qt_find_obj_child</b></a> ( QObject * parent, const char * type, const char * name )</div></li>
</ul>
<hr><a name="details"></a><h2>Detailed Description</h2>
The QObject class is the base class of all Qt objects.
<p>
<p> QObject is the heart of the <a href="object.html">Qt object model.</a> The central feature in this model is a very powerful
mechanism for seamless object communication called <a href="signalsandslots.html">signals and slots</a>. You can can connect
a signal to a slot with <a href="#connect">connect</a>() and destroy the connection with
<a href="#disconnect">disconnect</a>(). To avoid never ending notification loops you can
temporarily block signals with <a href="#blockSignals">blockSignals</a>(). The protected
functions <a href="#connectNotify">connectNotify</a>() and <a href="#disconnectNotify">disconnectNotify</a>() make it possible to
track connections.
<p> QObjects organize themselves in object trees. When you create a
QObject with another object as parent, the object will automatically
do an <a href="#insertChild">insertChild</a>() on the parent and thus show up in the parent's
<a href="#children">children</a>() list. The parent takes ownership of the object i.e. it
will automatically delete its children in its destructor. You can
look for an object by name and optionally type using <a href="#child">child</a>() or
<a href="#queryList">queryList</a>(), and get the list of tree roots using <a href="#objectTrees">objectTrees</a>().
<p> Every object has an object <a href="#name">name</a>() and can report its <a href="#className">className</a>() and
whether it <a href="#inherits">inherits</a>() another class in the QObject inheritance
hierarchy.
<p> When an object is deleted, it emits a <a href="#destroyed">destroyed</a>() signal. You can
catch this signal to avoid dangling references to QObjects. The
<a href="qguardedptr.html">QGuardedPtr</a> class provides an elegant way to use this feature.
<p> QObjects can receive events through <a href="#event">event</a>() and filter the events of
other objects. See <a href="#installEventFilter">installEventFilter</a>() and <a href="#eventFilter">eventFilter</a>() for
details. A convenience handler <a href="#childEvent">childEvent</a>() can be reimplemented to
catch child events.
<p> Last but not least, QObject provides the basic timer support in Qt;
see <a href="qtimer.html">QTimer</a> for high-level support for timers.
<p> Notice that the <a href="metaobjects.html#Q_OBJECT">Q_OBJECT</a> macro is mandatory for any object that
implements signals, slots or properties. You also need to run the <a href="moc.html">moc program (Meta Object Compiler)</a> on the source file.
We strongly recommend the use of this macro in <em>all</em> subclasses of QObject
regardless of whether or not they actually use signals, slots and
properties, since failure to do so may lead certain functions to
exhibit undefined behaviour.
<p> All Qt widgets inherit QObject. The convenience function
<a href="#isWidgetType">isWidgetType</a>() returns whether an object is actually a widget. It
is much faster than <a href="#inherits">inherits</a>( "QWidget" ).
<p> Some QObject functions, e.g. <a href="#children">children</a>(), <a href="#objectTrees">objectTrees</a>() and
<a href="#queryList">queryList</a>() return a QObjectList. A QObjectList is a <a href="qptrlist.html">QPtrList</a> of
QObjects. QObjectLists support the same operations as QPtrLists and
have an iterator class, QObjectListIt.
<p>See also <a href="objectmodel.html">Object Model</a>.
<hr><h2>Member Function Documentation</h2>
<h3 class=fn><a name="QObject"></a>QObject::QObject ( <a href="qobject.html">QObject</a> * parent = 0, const char * name = 0 )
</h3>
Constructs an object with the parent object <em>parent</em> and a <em>name</em>.
<p> The parent of an object may be viewed as the object's owner. For
instance, a <a href="qdialog.html">dialog box</a> is the parent of the
"OK" and "Cancel" buttons it contains.
<p> The destructor of a parent object destroys all child objects.
<p> Setting <em>parent</em> to 0 constructs an object with no parent.
If the object is a widget, it will become a top-level window.
<p> The object name is some text that can be used to identify a QObject.
It's particularly useful in conjunction with
<a href="designer-manual.html"><i>Qt Designer</i></a>.
You can find an object by name (and type) using <a href="#child">child</a>(). To find
several objects use <a href="#queryList">queryList</a>().
<p> <p>See also <a href="#parent">parent</a>(), <a href="#name-prop">name</a>, <a href="#child">child</a>() and <a href="#queryList">queryList</a>().
<h3 class=fn><a name="~QObject"></a>QObject::~QObject ()<tt> [virtual]</tt>
</h3>
Destroys the object, deleting all its child objects.
<p> All signals to and from the object are automatically disconnected.
<p> <b>Warning:</b> All child objects are deleted. If any of these objects are
on the stack or global, sooner or later your program will crash. We do
not recommend holding pointers to child objects from outside the parent.
If you still do, the <a href="#destroyed">QObject::destroyed</a>() signal gives you an
opportunity to detect when an object is destroyed.
<h3 class=fn>void <a name="blockSignals"></a>QObject::blockSignals ( bool block )
</h3>
Blocks signals if <em>block</em> is TRUE, or unblocks signals if <em>block</em> is FALSE.
<p> Emitted signals disappear into hyperspace if signals are blocked.
<p>Example: <a href="rot-example.html#x580">rot13/rot13.cpp</a>.
<h3 class=fn>bool <a name="checkConnectArgs"></a>QObject::checkConnectArgs ( const char * signal, const <a href="qobject.html">QObject</a> * receiver, const char * member )<tt> [virtual protected]</tt>
</h3>
<p> Returns TRUE if the <em>signal</em> and the <em>member</em> arguments are compatible;
otherwise returns FALSE. (The <em>receiver</em> argument is currently ignored.)
<p> <b>Warning:</b>
We recommend that you use the default implementation and do not
reimplement this function.
<p>
<h3 class=fn><a href="qobject.html">QObject</a> * <a name="child"></a>QObject::child ( const char * objName, const char * inheritsClass = 0, bool recursiveSearch = TRUE )
</h3> Searches the children and optionally grandchildren of this object,
and returns a child that is called <em>objName</em> that inherits <em>inheritsClass</em>. If <em>inheritsClass</em> is 0 (the default), any class
matches.
<p> If <em>recursiveSearch</em> is TRUE (the default), <a href="#child">child</a>() performs a
depth-first search of the object's children.
<p> If there is no such object, this function returns 0. If there are
more than one, the first one found is retured; if you need
all of them, use <a href="#queryList">queryList</a>().
<h3 class=fn>void <a name="childEvent"></a>QObject::childEvent ( <a href="qchildevent.html">QChildEvent</a> * )<tt> [virtual protected]</tt>
</h3>
This event handler can be reimplemented in a subclass to receive
child events.
<p> Child events are sent to objects when children are inserted or removed.
<p> Note that events with <a href="qevent.html#type">QEvent::type</a>() <a href="qevent.html#Type-enum">QEvent::ChildInserted</a> are
posted (with <a href="qapplication.html#postEvent">QApplication::postEvent</a>()) to make sure that the
child's construction is completed before this function is called.
<p> Note that if a child is removed immediately after it is inserted, the
<tt>ChildInserted</tt> event may be suppressed, but the <tt>ChildRemoved</tt>
event will always be sent. In this case there will be a <tt>ChildRemoved</tt>
event without a corresponding <tt>ChildInserted</tt> event.
<p> If you change state based on <tt>ChildInserted</tt> events, call
<a href="qwidget.html#constPolish">QWidget::constPolish</a>(), or do
<pre>
QApplication::<a href="qapplication.html#sendPostedEvents">sendPostedEvents</a>( this, QEvent::ChildInserted );
</pre>
in functions that depend on the state. One notable example is
<a href="qwidget.html#sizeHint">QWidget::sizeHint</a>().
<p> <p>See also <a href="#event">event</a>() and <a href="qchildevent.html">QChildEvent</a>.
<p>Reimplemented in <a href="qmainwindow.html#childEvent">QMainWindow</a> and <a href="qsplitter.html#childEvent">QSplitter</a>.
<h3 class=fn>const QObjectList * <a name="children"></a>QObject::children () const
</h3>
Returns a list of child objects, or 0 if this object has no children.
<p> The QObjectList class is defined in the qobjectlist.h header file.
<p> The first child added is the <a href="qptrlist.html#first">first</a>
object in the list and the last child added is the <a href="qptrlist.html#last">last</a> object in the list, i.e. new children
are appended at the end.
<p> Note that the list order changes when <a href="qwidget.html">QWidget</a> children are <a href="qwidget.html#raise">raised</a> or <a href="qwidget.html#lower">lowered.</a> A widget that is raised becomes the last object in
the list, and a widget that is lowered becomes the first object in
the list.
<p> <p>See also <a href="#child">child</a>(), <a href="#queryList">queryList</a>(), <a href="#parent">parent</a>(), <a href="#insertChild">insertChild</a>() and <a href="#removeChild">removeChild</a>().
<h3 class=fn>const char * <a name="className"></a>QObject::className () const
</h3>
<p> Returns the class name of this object.
<p> This function is generated by the <a href="metaobjects.html">Meta Object
Compiler.</a>
<p> <b>Warning:</b> This function will return a wrong name if the class
definition lacks the <a href="metaobjects.html#Q_OBJECT">Q_OBJECT</a> macro.
<p> <p>See also <a href="#name-prop">name</a>, <a href="#inherits">inherits</a>(), <a href="#isA">isA</a>() and <a href="#isWidgetType">isWidgetType</a>().
<p>Example: <a href="sql.html#x2349">sql/overview/custom1/main.cpp</a>.
<h3 class=fn>bool <a name="connect"></a>QObject::connect ( const <a href="qobject.html">QObject</a> * sender, const char * signal, const <a href="qobject.html">QObject</a> * receiver, const char * member )<tt> [static]</tt>
</h3> Connects <em>signal</em> from the <em>sender</em> object to <em>member</em> in object
<em>receiver</em>, and returns TRUE if the connection succeeds; otherwise
returns FALSE.
<p> You must use the SIGNAL() and SLOT() macros when specifying the <em>signal</em>
and the <em>member</em>, for example:
<pre>
<a href="qlabel.html">QLabel</a> *label = new <a href="qlabel.html">QLabel</a>;
<a href="qscrollbar.html">QScrollBar</a> *scroll = new <a href="qscrollbar.html">QScrollBar</a>;
QObject::<a href="#connect">connect</a>( scroll, SIGNAL(<a href="qscrollbar.html#valueChanged">valueChanged</a>(int)),
label, SLOT(<a href="qlabel.html#setNum">setNum</a>(int)) );
</pre>
<p> This example ensures that the label always displays the current scroll bar
value.
<p> A signal can also be connected to another signal:
<p> <pre>
class MyWidget : public <a href="qwidget.html">QWidget</a>
{
<a href="metaobjects.html#Q_OBJECT">Q_OBJECT</a>
public:
MyWidget();
signals:
void myUsefulSignal();
private:
<a href="qpushbutton.html">QPushButton</a> *aButton;
};
MyWidget::MyWidget()
{
aButton = new <a href="qpushbutton.html">QPushButton</a>( this );
<a href="#connect">connect</a>( aButton, SIGNAL(<a href="qbutton.html#clicked">clicked</a>()), SIGNAL(myUsefulSignal()) );
}
</pre>
<p> In this example, the MyWidget constructor relays a signal from a
private member variable, and makes it available under a name that
relates to MyWidget.
<p> A signal can be connected to many slots and signals. Many signals
can be connected to one slot.
<p> If a signal is connected to several slots, the slots are activated
in an arbitrary order when the signal is emitted.
<p> The function returns TRUE if it successfully connects the signal to
the slot. It will return FALSE if it cannot create the connection,
for example, if QObject is unable to verify the existence of either
<em>signal</em> or <em>member</em>, or if their signatures aren't compatible.
<p> <p>See also <a href="#disconnect">disconnect</a>().
<p>Examples: <a href="qactiongroup.html#x20">action/actiongroup/editor.cpp</a>, <a href="qaction-application-example.html#x2054">action/main.cpp</a>, <a href="addressbook-example.html#x1998">addressbook/main.cpp</a>, <a href="simple-application-example.html#x1954">application/main.cpp</a>, <a href="iconview-example.html#x1351">iconview/main.cpp</a>, <a href="mdi-example.html#x1197">mdi/main.cpp</a> and <a href="t2.html#x2104">t2/main.cpp</a>.
<h3 class=fn>bool <a name="connect-2"></a>QObject::connect ( const <a href="qobject.html">QObject</a> * sender, const char * signal, const char * member ) const
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Connects <em>signal</em> from the <em>sender</em> object to this object's <em>member</em>.
<p> Equivalent to: <tt>QObject::connect(sender, signal, this, member)</tt>.
<p> <p>See also <a href="#disconnect">disconnect</a>().
<h3 class=fn>void <a name="connectNotify"></a>QObject::connectNotify ( const char * signal )<tt> [virtual protected]</tt>
</h3>
<p> This virtual function is called when something has been connected to
<em>signal</em> in this object.
<p> <b>Warning:</b>
This function violates the object-oriented principle of modularity.
However, it might be useful when you need to perform expensive
initialization only if something is connected to a signal.
<p> <p>See also <a href="#connect">connect</a>() and <a href="#disconnectNotify">disconnectNotify</a>().
<h3 class=fn>void <a name="customEvent"></a>QObject::customEvent ( <a href="qcustomevent.html">QCustomEvent</a> * )<tt> [virtual protected]</tt>
</h3>
This event handler can be reimplemented in a subclass to receive
custom events. Custom events are user-defined events with a type
value at least as large as the "User" item of the <a href="qevent.html#Type-enum">QEvent::Type</a> enum,
and is typically a <a href="qcustomevent.html">QCustomEvent</a> or QCustomEvent subclass.
<p> <p>See also <a href="#event">event</a>() and <a href="qcustomevent.html">QCustomEvent</a>.
<h3 class=fn>void <a name="deleteLater"></a>QObject::deleteLater ()<tt> [slot]</tt>
</h3> Delete this object deferred.
<p> Instead of an immediate deletion this function schedules a deferred
delete event for processing when Qt returns to the main event loop.
<h3 class=fn>void <a name="destroyed"></a>QObject::destroyed ()<tt> [signal]</tt>
</h3>
<p> This signal is emitted immediately before the object is destroyed.
<p> All the objects's children are destroyed immediately after this signal
is emitted.
<h3 class=fn>void <a name="destroyed-2"></a>QObject::destroyed ( <a href="qobject.html">QObject</a> * obj )<tt> [signal]</tt>
</h3>
<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> This signal is emitted immediately before the object <em>obj</em> is destroyed.
<p> All the objects's children are destroyed immediately after this signal
is emitted.
<h3 class=fn>bool <a name="disconnect"></a>QObject::disconnect ( const <a href="qobject.html">QObject</a> * sender, const char * signal, const <a href="qobject.html">QObject</a> * receiver, const char * member )<tt> [static]</tt>
</h3>
Disconnects <em>signal</em> in object <em>sender</em> from <em>member</em> in object <em>receiver</em>.
<p> A signal-slot connection is removed when either of the objects
involved are destroyed.
<p> <a href="#disconnect">disconnect</a>() is typically used in three ways, as the following examples
demonstrate.
<ol type=1>
<li> Disconnect everything connected to an object's signals:
<pre>
<a href="#disconnect">disconnect</a>( myObject, 0, 0, 0 );
</pre>
equivalent to the non-static overloaded function
<pre>
myObject->disconnect();
</pre>
<li> Disconnect everything connected to a specific signal:
<pre>
<a href="#disconnect">disconnect</a>( myObject, SIGNAL(mySignal()), 0, 0 );
</pre>
equivalent to the non-static overloaded function
<pre>
myObject->disconnect( SIGNAL(mySignal()) );
</pre>
<li> Disconnect a specific receiver:
<pre>
<a href="#disconnect">disconnect</a>( myObject, 0, myReceiver, 0 );
</pre>
equivalent to the non-static overloaded function
<pre>
myObject->disconnect( myReceiver );
</pre>
</ol>
<p> 0 may be used as a wildcard, meaning "any signal", "any receiving
object", or "any slot in the receiving object", respectively.
<p> The <em>sender</em> may never be 0. (You cannot disconnect signals from
more than one object.)
<p> If <em>signal</em> is 0, it disconnects <em>receiver</em> and <em>member</em> from any
signal. If not, only the specified signal is disconnected.
<p> If <em>receiver</em> is 0, it disconnects anything connected to <em>signal</em>.
If not, slots in objects other than <em>receiver</em> are not disconnected.
<p> If <em>member</em> is 0, it disconnects anything that is connected to <em>receiver</em>. If not, only slots named <em>member</em> will be disconnected,
and all other slots are left alone. The <em>member</em> must be 0 if <em>receiver</em> is left out, so you cannot disconnect a specifically-named
slot on all objects.
<p> <p>See also <a href="#connect">connect</a>().
<h3 class=fn>bool <a name="disconnect-2"></a>QObject::disconnect ( const char * signal = 0, const <a href="qobject.html">QObject</a> * receiver = 0, const char * member = 0 )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Disconnects <em>signal</em> from <em>member</em> of <em>receiver</em>.
<p> A signal-slot connection is removed when either of the objects
involved are destroyed.
<h3 class=fn>bool <a name="disconnect-3"></a>QObject::disconnect ( const <a href="qobject.html">QObject</a> * receiver, const char * member = 0 )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Disconnects all signals in this object from <em>receiver</em>'s <em>member</em>.
<p> A signal-slot connection is removed when either of the objects
involved are destroyed.
<h3 class=fn>void <a name="disconnectNotify"></a>QObject::disconnectNotify ( const char * signal )<tt> [virtual protected]</tt>
</h3>
<p> This virtual function is called when something has been disconnected from
<em>signal</em> in this object.
<p> <b>Warning:</b>
This function violates the object-oriented principle of modularity.
However, it might be useful for optimizing access to expensive resources.
<p> <p>See also <a href="#disconnect">disconnect</a>() and <a href="#connectNotify">connectNotify</a>().
<h3 class=fn>void <a name="dumpObjectInfo"></a>QObject::dumpObjectInfo ()
</h3>
Dumps information about signal connections, etc. for this object to the
debug output.
<p> This function is useful for debugging, but does nothing if
the library has been compiled in release mode (i.e. without debugging
information).
<h3 class=fn>void <a name="dumpObjectTree"></a>QObject::dumpObjectTree ()
</h3>
Dumps a tree of children to the debug output.
<p> This function is useful for debugging, but does nothing if
the library has been compiled in release mode (i.e. without debugging
information).
<p>
<h3 class=fn>bool <a name="event"></a>QObject::event ( <a href="qevent.html">QEvent</a> * e )<tt> [virtual]</tt>
</h3>
This virtual function receives events to an object and should return
TRUE if the event <em>e</em> was recognized and processed.
<p> The <a href="#event">event</a>() function can be reimplemented to customize the behavior of
an object.
<p> <p>See also <a href="#installEventFilter">installEventFilter</a>(), <a href="#timerEvent">timerEvent</a>(), <a href="qapplication.html#sendEvent">QApplication::sendEvent</a>(), <a href="qapplication.html#postEvent">QApplication::postEvent</a>() and <a href="qwidget.html#event">QWidget::event</a>().
<p>Reimplemented in <a href="qwidget.html#event">QWidget</a>.
<h3 class=fn>bool <a name="eventFilter"></a>QObject::eventFilter ( <a href="qobject.html">QObject</a> * watched, <a href="qevent.html">QEvent</a> * e )<tt> [virtual]</tt>
</h3>
Filters events if this object has been installed as an event filter for
the <em>watched</em> object.
<p> In your reimplementation of this function, if you want to filter
the event <em>e</em>, out, i.e. stop it being handled further, return TRUE;
otherwise return FALSE.
<p> <b>Warning:</b>
If you delete the receiver object in this function, be sure to return TRUE.
Otherwise, Qt will forward the event to the deleted object and the
program might crash.
<p> <p>See also <a href="#installEventFilter">installEventFilter</a>().
<p>Reimplemented in <a href="qaccel.html#eventFilter">QAccel</a>, <a href="qscrollview.html#eventFilter">QScrollView</a> and <a href="qspinbox.html#eventFilter">QSpinBox</a>.
<h3 class=fn>bool <a name="highPriority"></a>QObject::highPriority () const
</h3>
Returns TRUE if the object is a high-priority object, or FALSE if it is a
standard-priority object.
<p> High-priority objects are placed first in QObject's list of children
on the assumption that they will be referenced very often.
<h3 class=fn>bool <a name="inherits"></a>QObject::inherits ( const char * clname ) const
</h3>
Returns TRUE if this object is an instance of a class that inherits
<em>clname</em>, and <em>clname</em> inherits QObject; otherwise returns FALSE.
<p> A class is considered to inherit itself.
<p> Example:
<pre>
<a href="qtimer.html">QTimer</a> *t = new <a href="qtimer.html">QTimer</a>; // QTimer inherits QObject
t-><a href="#inherits">inherits</a>( "QTimer" ); // returns TRUE
t-><a href="#inherits">inherits</a>( "QObject" ); // returns TRUE
t-><a href="#inherits">inherits</a>( "QButton" ); // returns FALSE
// QScrollBar inherits QWidget and QRangeControl
<a href="qscrollbar.html">QScrollBar</a> *s = new <a href="qscrollbar.html">QScrollBar</a>( 0 );
s-><a href="#inherits">inherits</a>( "QWidget" ); // returns TRUE
s-><a href="#inherits">inherits</a>( "QRangeControl" ); // returns FALSE
</pre>
<p> (<a href="qrangecontrol.html">QRangeControl</a> is not a QObject.)
<p> <p>See also <a href="#isA">isA</a>() and <a href="#metaObject">metaObject</a>().
<p>Examples: <a href="statistics-example.html#x2454">table/statistics/statistics.cpp</a>, <a href="themes-example.html#x299">themes/metal.cpp</a> and <a href="themes-example.html#x226">themes/wood.cpp</a>.
<h3 class=fn>void <a name="insertChild"></a>QObject::insertChild ( <a href="qobject.html">QObject</a> * obj )<tt> [virtual]</tt>
</h3>
Inserts an object <em>obj</em> into the list of child objects.
<p> <b>Warning:</b> This function cannot be used to make one widget the child
widget of another widget. Child widgets can only be created by
setting the parent widget in the constructor or by calling
<a href="qwidget.html#reparent">QWidget::reparent</a>().
<p> <p>See also <a href="#removeChild">removeChild</a>() and <a href="qwidget.html#reparent">QWidget::reparent</a>().
<h3 class=fn>void <a name="installEventFilter"></a>QObject::installEventFilter ( const <a href="qobject.html">QObject</a> * obj )
</h3>
Installs an event filter <em>obj</em> on this object.
<p> An event filter is an object that receives all events that are sent to
this object. The filter can either stop the event or forward it to this
object. The event filter <em>obj</em> receives events via its <a href="#eventFilter">eventFilter</a>()
function. The eventFilter() function must return TRUE if the event
should be filtered, (i.e. stopped); otherwise it must return FALSE.
<p> If multiple event filters are installed on a single object, the
filter that was installed last is activated first.
<p> Example:
<pre>
#include <<a href="qwidget-h.html">qwidget.h</a>>
class MyWidget : public <a href="qwidget.html">QWidget</a>
{
<a href="metaobjects.html#Q_OBJECT">Q_OBJECT</a>
public:
MyWidget( <a href="qwidget.html">QWidget</a> *parent = 0, const char *name = 0 );
protected:
bool eventFilter( QObject *, QEvent * );
};
MyWidget::MyWidget( <a href="qwidget.html">QWidget</a> *parent, const char *name )
: <a href="qwidget.html">QWidget</a>( parent, name )
{
// install a filter on the parent (if any)
if ( parent )
parent-><a href="#installEventFilter">installEventFilter</a>( this );
}
bool MyWidget::<a href="#eventFilter">eventFilter</a>( QObject *o, QEvent *e )
{
if ( e->type() == QEvent::KeyPress ) {
// special processing for key press
<a href="qkeyevent.html">QKeyEvent</a> *k = (QKeyEvent *)e;
<a href="qapplication.html#qDebug">qDebug</a>( "Ate key press %d", k-><a href="qkeyevent.html#key">key</a>() );
return TRUE; // eat event
} else {
// standard event processing
return QWidget::eventFilter( o, e );
}
}
</pre>
<p> The <a href="qaccel.html">QAccel</a> class, for example, uses this technique to intercept
accelerator key presses.
<p> <b>Warning:</b>
If you delete the receiver object in your <a href="#eventFilter">eventFilter</a>() function, be
sure to return TRUE. If you return FALSE, Qt sends the event to the
deleted object and the program will crash.
<p> <p>See also <a href="#removeEventFilter">removeEventFilter</a>(), <a href="#eventFilter">eventFilter</a>() and <a href="#event">event</a>().
<h3 class=fn>bool <a name="isA"></a>QObject::isA ( const char * clname ) const
</h3>
Returns TRUE if this object is an instance of the class <em>clname</em>;
otherwise returns FALSE.
<p> Example:
<pre>
<a href="qtimer.html">QTimer</a> *t = new <a href="qtimer.html">QTimer</a>; // QTimer inherits QObject
t-><a href="#isA">isA</a>( "QTimer" ); // returns TRUE
t-><a href="#isA">isA</a>( "QObject" ); // returns FALSE
</pre>
<p> <p>See also <a href="#inherits">inherits</a>() and <a href="#metaObject">metaObject</a>().
<h3 class=fn>bool <a name="isWidgetType"></a>QObject::isWidgetType () const
</h3>
Returns TRUE if the object is a widget; otherwise returns FALSE.
<p> Calling this function is equivalent to calling <a href="#inherits">inherits</a>("QWidget"),
except that it is much faster.
<h3 class=fn>void <a name="killTimer"></a>QObject::killTimer ( int id )
</h3>
Kills the timer with timer identifier, <em>id</em>.
<p> The timer identifier is returned by <a href="#startTimer">startTimer</a>() when a timer event is
started.
<p> <p>See also <a href="#timerEvent">timerEvent</a>(), <a href="#startTimer">startTimer</a>() and <a href="#killTimers">killTimers</a>().
<h3 class=fn>void <a name="killTimers"></a>QObject::killTimers ()
</h3>
Kills all timers that this object has started.
<p> Note that using this function can cause hard-to-find bugs: it kills
timers started by sub- and superclasses as well as those started by
you, which is often not what you want. We recommend
using a <a href="qtimer.html">QTimer</a> or perhaps <a href="#killTimer">killTimer</a>().
<p> <p>See also <a href="#timerEvent">timerEvent</a>(), <a href="#startTimer">startTimer</a>() and <a href="#killTimer">killTimer</a>().
<h3 class=fn><a href="qmetaobject.html">QMetaObject</a> * <a name="metaObject"></a>QObject::metaObject () const
</h3>
Returns a pointer to the <a href="metaobjects.html#meta-object">meta object</a> of this object.
<p> A meta object contains information about a class that inherits
QObject, e.g. class name, superclass name, properties, signals and
slots. Every class that contains the <a href="metaobjects.html#Q_OBJECT">Q_OBJECT</a> macro will also
have a meta object.
<p> The meta object information is required by the signal/slot
connection mechanism and the property system. The functions <a href="#isA">isA</a>()
and <a href="#inherits">inherits</a>() also make use of the meta object.
<h3 class=fn>const char * <a name="name"></a>QObject::name () const
</h3><p>Returns the name of this object.
See the <a href="qobject.html#name-prop">"name"</a> property for details.
<h3 class=fn>const char * <a name="name-2"></a>QObject::name ( const char * defaultName ) const
</h3> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Returns the name of this object, or <em>defaultName</em> if the object
does not have a name.
<h3 class=fn><a href="qcstring.html">QCString</a> <a name="normalizeSignalSlot"></a>QObject::normalizeSignalSlot ( const char * signalSlot )<tt> [static protected]</tt>
</h3>
Normlizes the signal or slot definition <em>signalSlot</em> by removing
unnecessary whitespace.
<h3 class=fn>const QObjectList * <a name="objectTrees"></a>QObject::objectTrees ()<tt> [static]</tt>
</h3>
Returns a pointer to the list of all object trees (their root objects),
or 0 if there are no objects.
<p> The QObjectList class is defined in the qobjectlist.h header file.
<p> The latest root object created is the <a href="qptrlist.html#first">first</a> object in the list and the first root object added is
the <a href="qptrlist.html#last">last</a> object in the list.
<p> <p>See also <a href="#children">children</a>(), <a href="#parent">parent</a>(), <a href="#insertChild">insertChild</a>() and <a href="#removeChild">removeChild</a>().
<h3 class=fn><a href="qobject.html">QObject</a> * <a name="parent"></a>QObject::parent () const
</h3>
Returns a pointer to the parent object.
<p>See also <a href="#children">children</a>().
<h3 class=fn><a href="qvariant.html">QVariant</a> <a name="property"></a>QObject::property ( const char * name ) const<tt> [virtual]</tt>
</h3>
Returns the value of the object's <em>name</em> property.
<p> If no such property exists, the returned variant is invalid.
<p> Information about all available properties are provided through the
<a href="#metaObject">metaObject</a>().
<p> <p>See also <a href="#setProperty">setProperty</a>(), <a href="qvariant.html#isValid">QVariant::isValid</a>(), <a href="#metaObject">metaObject</a>(), <a href="qmetaobject.html#propertyNames">QMetaObject::propertyNames</a>() and <a href="qmetaobject.html#property">QMetaObject::property</a>().
<p>
<h3 class=fn>QObjectList * <a name="queryList"></a>QObject::queryList ( const char * inheritsClass = 0, const char * objName = 0, bool regexpMatch = TRUE, bool recursiveSearch = TRUE ) const
</h3> Searches the children and optionally grandchildren of this object,
and returns a list of those objects that are named or that match <em>objName</em> and inherit <em>inheritsClass</em>. If <em>inheritsClass</em> is 0 (the
default), all classes match. If <em>objName</em> is 0 (the default), all
object names match.
<p> If <em>regexpMatch</em> is TRUE (the default), <em>objName</em> is a <a href="qregexp.html#regular-expression">regular expression</a> that the objects's names must match. The syntax is that
of a <a href="qregexp.html">QRegExp</a>. If <em>regexpMatch</em> is FALSE, <em>objName</em> is a string
and object names must match it exactly.
<p> Note that <em>inheritsClass</em> uses single inheritance from QObject, the
way <a href="#inherits">inherits</a>() does. According to inherits(), <a href="qmenubar.html">QMenuBar</a> inherits
<a href="qwidget.html">QWidget</a> but not <a href="qmenudata.html">QMenuData</a>. This does not quite match reality, but is
the best that can be done on the wide variety of compilers Qt
supports.
<p> Finally, if <em>recursiveSearch</em> is TRUE (the default), <a href="#queryList">queryList</a>()
searches <em>n</em>th-generation as well as first-generation children.
<p> If all this seems a bit complex for your needs, the simpler
<a href="#child">child</a>() function may be what you want.
<p> This somewhat contrived example disables all the buttons in this
window:
<pre>
QObjectList *l = topLevelWidget()->queryList( "QButton" );
QObjectListIt it( *l ); // iterate over the buttons
QObject *obj;
while ( (obj = it.current()) != 0 ) {
// for each found object...
++it;
((QButton*)obj)->setEnabled( FALSE );
}
delete l; // delete the list, not the objects
</pre>
<p> <b>Warning:</b> Delete the list as soon you have finished using it.
The list contains pointers that may become invalid at almost any
time without notice (as soon as the user closes a window you may
have dangling pointers, for example).
<p> <p>See also <a href="#child">child</a>(), <a href="#children">children</a>(), <a href="#parent">parent</a>(), <a href="#inherits">inherits</a>(), <a href="#name-prop">name</a> and <a href="qregexp.html">QRegExp</a>.
<h3 class=fn>void <a name="removeChild"></a>QObject::removeChild ( <a href="qobject.html">QObject</a> * obj )<tt> [virtual]</tt>
</h3>
Removes the child object <em>obj</em> from the list of children.
<p> <b>Warning:</b>
This function will not remove a child widget from the screen.
It will only remove it from the parent widget's list of children.
<p> <p>See also <a href="#insertChild">insertChild</a>() and <a href="qwidget.html#reparent">QWidget::reparent</a>().
<h3 class=fn>void <a name="removeEventFilter"></a>QObject::removeEventFilter ( const <a href="qobject.html">QObject</a> * obj )
</h3>
Removes an event filter object <em>obj</em> from this object.
The request is ignored if such an event filter has not been installed.
<p> All event filters for this object are automatically removed when this
object is destroyed.
<p> It is always safe to remove an event filter, even during event filter
activation (i.e. from the <a href="#eventFilter">eventFilter</a>() function).
<p> <p>See also <a href="#installEventFilter">installEventFilter</a>(), <a href="#eventFilter">eventFilter</a>() and <a href="#event">event</a>().
<h3 class=fn>const <a href="qobject.html">QObject</a> * <a name="sender"></a>QObject::sender ()<tt> [protected]</tt>
</h3> Returns a pointer to the object that sent the signal, if called in a
slot before any function call or signal emission. Returns an
undefined value in all other cases.
<p> <b>Warning:</b> This function will return something apparently correct in
other cases as well. However, its value may change during any function
call, depending on what signal-slot connections are activated during
that call. In Qt 3.0 the value will change more often than in 2.x.
<p> <b>Warning:</b>
This function violates the object-oriented principle of modularity.
However, getting access to the sender might be practical when many
signals are connected to a single slot. The sender is undefined if
the slot is called as a normal C++ function.
<h3 class=fn>void <a name="setName"></a>QObject::setName ( const char * name )<tt> [virtual]</tt>
</h3>
Sets the object's name to <em>name</em>.
<h3 class=fn>bool <a name="setProperty"></a>QObject::setProperty ( const char * name, const <a href="qvariant.html">QVariant</a> & value )<tt> [virtual]</tt>
</h3>
Sets the object's property <em>name</em> to <em>value</em>.
<p> Returns TRUE if the operation was successful; otherwise returns FALSE.
<p> Information about all available properties is provided through the
<a href="#metaObject">metaObject</a>().
<p> <p>See also <a href="#property">property</a>(), <a href="#metaObject">metaObject</a>(), <a href="qmetaobject.html#propertyNames">QMetaObject::propertyNames</a>() and <a href="qmetaobject.html#property">QMetaObject::property</a>().
<h3 class=fn>bool <a name="signalsBlocked"></a>QObject::signalsBlocked () const
</h3>
Returns TRUE if signals are blocked; otherwise returns FALSE.
<p> Signals are not blocked by default.
<p>See also <a href="#blockSignals">blockSignals</a>().
<h3 class=fn>int <a name="startTimer"></a>QObject::startTimer ( int interval )
</h3>
Starts a timer and returns a timer identifier, or returns zero if
it could not start a timer.
<p> A timer event will occur every <em>interval</em> milliseconds until
<a href="#killTimer">killTimer</a>() or <a href="#killTimers">killTimers</a>() is called. If <em>interval</em> is 0, then
the timer event occurs once every time there are no more window system
events to process.
<p> The virtual <a href="#timerEvent">timerEvent</a>() function is called with the <a href="qtimerevent.html">QTimerEvent</a> event
parameter class when a timer event occurs. Reimplement this function to
get timer events.
<p> If multiple timers are running, the <a href="qtimerevent.html#timerId">QTimerEvent::timerId</a>() can be
used to find out which timer was activated.
<p> Example:
<pre>
class MyObject : public QObject
{
Q_OBJECT
public:
MyObject( QObject *parent = 0, const char *name = 0 );
protected:
void timerEvent( <a href="qtimerevent.html">QTimerEvent</a> * );
};
MyObject::MyObject( QObject *parent, const char *name )
: QObject( parent, name )
{
<a href="#startTimer">startTimer</a>( 50 ); // 50-millisecond timer
<a href="#startTimer">startTimer</a>( 1000 ); // 1-second timer
<a href="#startTimer">startTimer</a>( 60000 ); // 1-minute timer
}
void MyObject::<a href="#timerEvent">timerEvent</a>( <a href="qtimerevent.html">QTimerEvent</a> *e )
{
<a href="qapplication.html#qDebug">qDebug</a>( "timer event, id %d", e-><a href="qtimerevent.html#timerId">timerId</a>() );
}
</pre>
<p> There is practically no upper limit for the interval value (more than one
year is possible). Note that <a href="qtimer.html">QTimer</a>'s accuracy depends on the underlying
operating system and hardware. Most platforms support an accuracy of
20ms; some provide more. If Qt is unable to deliver the requested number
of timer clicks, it will silently discard some.
<p> The QTimer class provides a high-level programming interface with
one-shot timers and timer signals instead of events.
<p> <p>See also <a href="#timerEvent">timerEvent</a>(), <a href="#killTimer">killTimer</a>() and <a href="#killTimers">killTimers</a>().
<h3 class=fn>void <a name="timerEvent"></a>QObject::timerEvent ( <a href="qtimerevent.html">QTimerEvent</a> * )<tt> [virtual protected]</tt>
</h3>
This event handler can be reimplemented in a subclass to receive
timer events for the object.
<p> <a href="qtimer.html">QTimer</a> provides a higher-level interface to the timer functionality,
and also more general information about timers.
<p> <p>See also <a href="#startTimer">startTimer</a>(), <a href="#killTimer">killTimer</a>(), <a href="#killTimers">killTimers</a>() and <a href="#event">event</a>().
<p>Examples: <a href="biff-example.html#x1906">biff/biff.cpp</a>, <a href="dclock-example.html#x1764">dclock/dclock.cpp</a>, <a href="forever-example.html#x1481">forever/forever.cpp</a>, <a href="grapher-nsplugin-example.html#x2607">grapher/grapher.cpp</a>, <a href="qmag-example.html#x701">qmag/qmag.cpp</a> and <a href="xform-example.html#x86">xform/xform.cpp</a>.
<h3 class=fn><a href="qstring.html">QString</a> <a name="tr"></a>QObject::tr ( const char * sourceText, const char * comment ) const
</h3>
<p> Returns a translated version of <em>sourceText</em>, or <em>sourceText</em>
itself if there is no appropriate translated version. The
translation context is QObject with <em>comment</em> (null by default).
All QObject subclasses using the <a href="metaobjects.html#Q_OBJECT">Q_OBJECT</a> macro automatically have
a reimplementation of this function with the subclass name as
context.
<p> <p>See also <a href="#trUtf8">trUtf8</a>(), <a href="qapplication.html#translate">QApplication::translate</a>() and <a href="i18n.html">Internationalization with Qt</a>.
<p>Example: <a href="qdialog.html#x32">network/networkprotocol/view.cpp</a>.
<h3 class=fn><a href="qstring.html">QString</a> <a name="trUtf8"></a>QObject::trUtf8 ( const char * sourceText, const char * comment ) const
</h3>
<p> Returns a translated version of <em>sourceText</em>, or
<a href="qstring.html#fromUtf8">QString::fromUtf8</a>(<em>sourceText</em>) if there is no appropriate version.
It is otherwise identical to <a href="#tr">tr</a>(<em>sourceText</em>, <em>comment</em>).
<p> <p>See also <a href="#tr">tr</a>() and <a href="qapplication.html#translate">QApplication::translate</a>().
<hr><h2>Property Documentation</h2>
<h3 class=fn><a href="qcstring.html">QCString</a> <a name="name-prop"></a>name</h3>
<p>This property holds the name of this object.
<p>You can find an object by name (and type) using <a href="#child">child</a>(). You can
find a set of objects with <a href="#queryList">queryList</a>().
<p> The object name is set by the constructor or by the <a href="#setName">setName</a>()
function. The object name is not very useful in the current version
of Qt, but will become increasingly important in the future.
<p> If the object does not have a name, the <a href="#name">name</a>() function returns
"unnamed", so printf() (used in <a href="qapplication.html#qDebug">qDebug</a>()) will not be asked to output a null
pointer. If you want a null pointer to be returned for unnamed objects, you
can call name( 0 ).
<p> <pre>
<a href="qapplication.html#qDebug">qDebug</a>( "MyClass::setPrecision(): (%s) invalid precision %f",
<a href="#name">name</a>(), newPrecision );
</pre>
<p> <p>See also <a href="#className">className</a>(), <a href="#child">child</a>() and <a href="#queryList">queryList</a>().
<p>Set this property's value with <a href="#setName">setName</a>() and get this property's value with <a href="#name">name</a>().
<hr><h2>Related Functions</h2>
<h3 class=fn>void * <a name="qt_find_obj_child"></a>qt_find_obj_child ( <a href="qobject.html">QObject</a> * parent, const char * type, const char * name )
</h3>
<p> Returns a pointer to the object named <em>name</em> that inherits <em>type</em>
and with a given <em>parent</em>.
<p> Returns 0 if there is no such child.
<p> <pre>
<a href="qlistbox.html">QListBox</a> *c = (QListBox *) <a href="#qt_find_obj_child">qt_find_obj_child</a>( myWidget, "QListBox",
"my list box" );
if ( c )
c-><a href="qlistbox.html#insertItem">insertItem</a>( "another string" );
</pre>
<!-- eof -->
<hr><p>
This file is part of the <a href="index.html">Qt toolkit</a>.
Copyright © 1995-2001
<a href="http://www.trolltech.com/">Trolltech</a>. All Rights Reserved.<p><address><hr><div align=center>
<table width=100% cellspacing=0 border=0><tr>
<td>Copyright © 2001
<a href="http://www.trolltech.com">Trolltech</a><td><a href="http://www.trolltech.com/trademarks.html">Trademarks</a>
<td align=right><div align=right>Qt version 3.0.2</div>
</table></div></address></body>
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