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QObject(3qt)							  QObject(3qt)

NAME
       QObject - The base class of all Qt objects

SYNOPSIS
       All the functions in this class are reentrant when Qt is built with
       thread support.</p>

       #include <qobject.h>

       Inherits Qt.

       Inherited by QAccel, QAccessibleObject, QAction, QApplication,
       QAssistantClient, QDataPump, QAxObject, QAxScript, QAxScriptManager,
       QWidget, QCanvas, QStyle, QClipboard, QCopChannel, QDns, QLayout,
       QDragObject, QEditorFactory, QEventLoop, QFileIconProvider,
       QNetworkProtocol, QWSKeyboardHandler, QNetworkOperation, QNPInstance,
       QObjectCleanupHandler, QProcess, QServerSocket, QSessionManager,
       QSignal, QSignalMapper, QSocket, QSocketNotifier, QSound, QSqlDatabase,
       QSqlDriver, QSqlForm, QStyleSheet, QTimer, QToolTipGroup, QTranslator,
       QUrlOperator, and QValidator.

   Public Members
       QObject ( QObject * parent = 0, const char * name = 0 )
       virtual ~QObject ()
       virtual const char * className () const
       virtual QMetaObject * metaObject () const
       virtual bool event ( QEvent * e )
       virtual bool eventFilter ( QObject * watched, QEvent * e )
       bool isA ( const char * clname ) const
       bool inherits ( const char * clname ) const
       const char * name () const
       const char * name ( const char * defaultName ) const
       virtual void setName ( const char * name )
       bool isWidgetType () const
       bool highPriority () const
       bool signalsBlocked () const
       void blockSignals ( bool block )
       int startTimer ( int interval )
       void killTimer ( int id )
       void killTimers ()
       QObject * child ( const char * objName, const char * inheritsClass = 0,
	   bool recursiveSearch = TRUE )
       const QObjectList * children () const
       QObjectList * queryList ( const char * inheritsClass = 0, const char *
	   objName = 0, bool regexpMatch = TRUE, bool recursiveSearch = TRUE )
	   const
       virtual void insertChild ( QObject * obj )
       virtual void removeChild ( QObject * obj )
       void installEventFilter ( const QObject * filterObj )
       void removeEventFilter ( const QObject * obj )
       bool connect ( const QObject * sender, const char * signal, const char
	   * member ) const
       bool disconnect ( const char * signal = 0, const QObject * receiver =
	   0, const char * member = 0 )
       bool disconnect ( const QObject * receiver, const char * member = 0 )
       void dumpObjectTree ()
       void dumpObjectInfo ()
       virtual bool setProperty ( const char * name, const QVariant & value )
       virtual QVariant property ( const char * name ) const
       QObject * parent () const

   Public Slots
       void deleteLater ()

   Signals
       void destroyed ()
       void destroyed ( QObject * obj )

   Static Public Members
       QString tr ( const char * sourceText, const char * comment )
       QString trUtf8 ( const char * sourceText, const char * comment )
       const QObjectList * objectTrees ()
       bool connect ( const QObject * sender, const char * signal, const
	   QObject * receiver, const char * member )
       bool disconnect ( const QObject * sender, const char * signal, const
	   QObject * receiver, const char * member )

   Properties
       QCString name - the name of this object

   Protected Members
       const QObject * sender ()
       virtual void timerEvent ( QTimerEvent * )
       virtual void childEvent ( QChildEvent * )
       virtual void customEvent ( QCustomEvent * )
       virtual void connectNotify ( const char * signal )
       virtual void disconnectNotify ( const char * signal )
       virtual bool checkConnectArgs ( const char * signal, const QObject *
	   receiver, const char * member )

   Static Protected Members
       QCString normalizeSignalSlot ( const char * signalSlot )

RELATED FUNCTION DOCUMENTATION
       void * qt_find_obj_child ( QObject * parent, const char * type, const
	   char * name )

DESCRIPTION
       The QObject class is the base class of all Qt objects.

       QObject is the heart of the Qt object model. The central feature in
       this model is a very powerful mechanism for seamless object
       communication called signals and slots. You can connect a signal to a
       slot with connect() and destroy the connection with disconnect(). To
       avoid never ending notification loops you can temporarily block signals
       with blockSignals(). The protected functions connectNotify() and
       disconnectNotify() make it possible to track connections.

       QObjects organize themselves in object trees. When you create a QObject
       with another object as parent, the object will automatically do an
       insertChild() on the parent and thus show up in the parent's children()
       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 child() or queryList(), and
       get the list of tree roots using objectTrees().

       Every object has an object name() and can report its className() and
       whether it inherits() another class in the QObject inheritance
       hierarchy.

       When an object is deleted, it emits a destroyed() signal. You can catch
       this signal to avoid dangling references to QObjects. The QGuardedPtr
       class provides an elegant way to use this feature.

       QObjects can receive events through event() and filter the events of
       other objects. See installEventFilter() and eventFilter() for details.
       A convenience handler, childEvent(), can be reimplemented to catch
       child events.

       Last but not least, QObject provides the basic timer support in Qt; see
       QTimer for high-level support for timers.

       Notice that the Q_OBJECT macro is mandatory for any object that
       implements signals, slots or properties. You also need to run the moc
       program (Meta Object Compiler) on the source file. We strongly
       recommend the use of this macro in all 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.

       All Qt widgets inherit QObject. The convenience function isWidgetType()
       returns whether an object is actually a widget. It is much faster than
       inherits( "QWidget" ).

       Some QObject functions, e.g. children(), objectTrees() and queryList()
       return a QObjectList. A QObjectList is a QPtrList of QObjects.
       QObjectLists support the same operations as QPtrLists and have an
       iterator class, QObjectListIt.

       See also Object Model.

MEMBER FUNCTION DOCUMENTATION
QObject::QObject ( QObject * parent = 0, const char * name = 0 )
       Constructs an object called name with parent object, parent.

       The parent of an object may be viewed as the object's owner. For
       instance, a dialog box is the parent of the" OK" and "Cancel" buttons
       it contains.

       The destructor of a parent object destroys all child objects.

       Setting parent to 0 constructs an object with no parent. If the object
       is a widget, it will become a top-level window.

       The object name is some text that can be used to identify a QObject.
       It's particularly useful in conjunction with Qt Designer. You can find
       an object by name (and type) using child(). To find several objects use
       queryList().

       See also parent(), name, child(), and queryList().

QObject::~QObject () [virtual]
       Destroys the object, deleting all its child objects.

       All signals to and from the object are automatically disconnected.

       Warning: 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 QObject::destroyed() signal gives you an opportunity
       to detect when an object is destroyed.

       Warning: Deleting a QObject while pending events are waiting to be
       delivered can cause a crash. You must not delete the QObject directly
       from a thread that is not the GUI thread. Use the
       QObject::deleteLater() method instead, which will cause the event loop
       to delete the object after all pending events have been delivered to
       the object.

void QObject::blockSignals ( bool block )
       Blocks signals if block is TRUE, or unblocks signals if block is FALSE.

       Emitted signals disappear into hyperspace if signals are blocked. Note
       that the destroyed() signals will be emitted even if the signals for
       this object have been blocked.

       Examples:

bool QObject::checkConnectArgs ( const char * signal, const QObject *
       receiver, const char * member ) [virtual protected]
       Returns TRUE if the signal and the member arguments are compatible;
       otherwise returns FALSE. (The receiver argument is currently ignored.)

       Warning: We recommend that you use the default implementation and do
       not reimplement this function.

QObject * QObject::child ( const char * objName, const char * inheritsClass =
       0, bool recursiveSearch = TRUE )
       Searches the children and optionally grandchildren of this object, and
       returns a child that is called objName that inherits inheritsClass. If
       inheritsClass is 0 (the default), any class matches.

       If recursiveSearch is TRUE (the default), child() performs a depth-
       first search of the object's children.

       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
       queryList().

void QObject::childEvent ( QChildEvent * ) [virtual protected]
       This event handler can be reimplemented in a subclass to receive child
       events.

       Child events are sent to objects when children are inserted or removed.

       Note that events with QEvent::type() QEvent::ChildInserted are posted
       (with QApplication::postEvent()) to make sure that the child's
       construction is completed before this function is called.

       If a child is removed immediately after it is inserted, the
       ChildInserted event may be suppressed, but the ChildRemoved event will
       always be sent. In such cases it is possible that there will be a
       ChildRemoved event without a corresponding ChildInserted event.

       If you change state based on ChildInserted events, call
       QWidget::constPolish(), or do

	       QApplication::sendPostedEvents( this, QEvent::ChildInserted );
       in functions that depend on the state. One notable example is
       QWidget::sizeHint().

       See also event() and QChildEvent.

       Reimplemented in QMainWindow and QSplitter.

const QObjectList * QObject::children () const
       Returns a list of child objects, or 0 if this object has no children.

       The QObjectList class is defined in the qobjectlist.h header file.

       The first child added is the first object in the list and the last
       child added is the last object in the list, i.e. new children are
       appended at the end.

       Note that the list order changes when QWidget children are raised or
       lowered. 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.

       See also child(), queryList(), parent(), insertChild(), and
       removeChild().

const char * QObject::className () const [virtual]
       Returns the class name of this object.

       This function is generated by the Meta Object Compiler.

       Warning: This function will return the wrong name if the class
       definition lacks the Q_OBJECT macro.

       See also name, inherits(), isA(), and isWidgetType().

       Example: sql/overview/custom1/main.cpp.

bool QObject::connect ( const QObject * sender, const char * signal, const
       QObject * receiver, const char * member ) [static]
       Connects signal from the sender object to member in object receiver,
       and returns TRUE if the connection succeeds; otherwise returns FALSE.

       You must use the SIGNAL() and SLOT() macros when specifying the signal
       and the member, for example:

	   QLabel     *label  = new QLabel;
	   QScrollBar *scroll = new QScrollBar;
	   QObject::connect( scroll, SIGNAL(valueChanged(int)),
			     label,  SLOT(setNum(int)) );

       This example ensures that the label always displays the current scroll
       bar value. Note that the signal and slots parameters must not contain
       any variable names, only the type. E.g. the following would not work
       and return FALSE: QObject::connect( scroll, SIGNAL(valueChanged(int
       v)), label, SLOT(setNum(int v)) );

       A signal can also be connected to another signal:

	   class MyWidget : public QWidget
	   {
	       Q_OBJECT
	   public:
	       MyWidget();
	   signals:
	       void myUsefulSignal();
	   private:
	       QPushButton *aButton;
	   };
	   MyWidget::MyWidget()
	   {
	       aButton = new QPushButton( this );
	       connect( aButton, SIGNAL(clicked()), SIGNAL(myUsefulSignal()) );
	   }

       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.

       A signal can be connected to many slots and signals. Many signals can
       be connected to one slot.

       If a signal is connected to several slots, the slots are activated in
       an arbitrary order when the signal is emitted.

       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 signal
       or member, or if their signatures aren't compatible.

       A signal is emitted for every connection you make, so if you duplicate
       a connection, two signals will be emitted. You can always break a
       connection using disconnect().

       See also disconnect().

       Examples:

bool QObject::connect ( const QObject * sender, const char * signal, const
       char * member ) const
       This is an overloaded member function, provided for convenience. It
       behaves essentially like the above function.

       Connects signal from the sender object to this object's member.

       Equivalent to: QObject::connect(sender, signal, this, member).

       See also disconnect().

void QObject::connectNotify ( const char * signal ) [virtual protected]
       This virtual function is called when something has been connected to
       signal in this object.

       Warning: 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.

       See also connect() and disconnectNotify().

void QObject::customEvent ( QCustomEvent * ) [virtual protected]
       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 QEvent::Type enum, and is
       typically a QCustomEvent or QCustomEvent subclass.

       See also event() and QCustomEvent.

void QObject::deleteLater () [slot]
       Performs a deferred deletion of this object.

       Instead of an immediate deletion this function schedules a deferred
       delete event for processing when Qt returns to the main event loop.

       Example: table/bigtable/main.cpp.

void QObject::destroyed () [signal]
       This signal is emitted when the object is being destroyed.

       Note that the signal is emitted by the QObject destructor, so the
       object's virtual table is already degenerated at this point, and it is
       not safe to call any functions on the object emitting the signal. This
       signal can not be blocked.

       All the objects's children are destroyed immediately after this signal
       is emitted.

void QObject::destroyed ( QObject * obj ) [signal]
       This is an overloaded member function, provided for convenience. It
       behaves essentially like the above function.

       This signal is emitted immediately before the object obj is destroyed,
       and can not be blocked.

       All the objects's children are destroyed immediately after this signal
       is emitted.

bool QObject::disconnect ( const QObject * sender, const char * signal, const
       QObject * receiver, const char * member ) [static]
       Disconnects signal in object sender from member in object receiver.

       A signal-slot connection is removed when either of the objects involved
       are destroyed.

       disconnect() is typically used in three ways, as the following examples
       demonstrate. <ol type=1>

       1      Disconnect everything connected to an object's signals:

		     disconnect( myObject, 0, 0, 0 );
	      equivalent to the non-static overloaded function

		     myObject->disconnect();

       2      Disconnect everything connected to a specific signal:

		     disconnect( myObject, SIGNAL(mySignal()), 0, 0 );
	      equivalent to the non-static overloaded function

		     myObject->disconnect( SIGNAL(mySignal()) );

       3      Disconnect a specific receiver:

		     disconnect( myObject, 0, myReceiver, 0 );
	      equivalent to the non-static overloaded function

		     myObject->disconnect(  myReceiver );

       0 may be used as a wildcard, meaning "any signal", "any receiving
       object", or "any slot in the receiving object", respectively.

       The sender may never be 0. (You cannot disconnect signals from more
       than one object in a single call.)

       If signal is 0, it disconnects receiver and member from any signal. If
       not, only the specified signal is disconnected.

       If receiver is 0, it disconnects anything connected to signal. If not,
       slots in objects other than receiver are not disconnected.

       If member is 0, it disconnects anything that is connected to receiver.
       If not, only slots named member will be disconnected, and all other
       slots are left alone. The member must be 0 if receiver is left out, so
       you cannot disconnect a specifically-named slot on all objects.

       See also connect().

bool QObject::disconnect ( const char * signal = 0, const QObject * receiver =
       0, const char * member = 0 )
       This is an overloaded member function, provided for convenience. It
       behaves essentially like the above function.

       Disconnects signal from member of receiver.

       A signal-slot connection is removed when either of the objects involved
       are destroyed.

bool QObject::disconnect ( const QObject * receiver, const char * member = 0 )

       This is an overloaded member function, provided for convenience. It
       behaves essentially like the above function.

       Disconnects all signals in this object from receiver's member.

       A signal-slot connection is removed when either of the objects involved
       are destroyed.

void QObject::disconnectNotify ( const char * signal ) [virtual protected]
       This virtual function is called when something has been disconnected
       from signal in this object.

       Warning: This function violates the object-oriented principle of
       modularity. However, it might be useful for optimizing access to
       expensive resources.

       See also disconnect() and connectNotify().

void QObject::dumpObjectInfo ()
       Dumps information about signal connections, etc. for this object to the
       debug output.

       This function is useful for debugging, but does nothing if the library
       has been compiled in release mode (i.e. without debugging information).

void QObject::dumpObjectTree ()
       Dumps a tree of children to the debug output.

       This function is useful for debugging, but does nothing if the library
       has been compiled in release mode (i.e. without debugging information).

bool QObject::event ( QEvent * e ) [virtual]
       This virtual function receives events to an object and should return
       TRUE if the event e was recognized and processed.

       The event() function can be reimplemented to customize the behavior of
       an object.

       See also installEventFilter(), timerEvent(), QApplication::sendEvent(),
       QApplication::postEvent(), and QWidget::event().

       Reimplemented in QWidget.

bool QObject::eventFilter ( QObject * watched, QEvent * e ) [virtual]
       Filters events if this object has been installed as an event filter for
       the watched object.

       In your reimplementation of this function, if you want to filter the
       event e, out, i.e. stop it being handled further, return TRUE;
       otherwise return FALSE.

       Example:

	   class MyMainWindow : public QMainWindow
	   {
	   public:
	       MyMainWindow( QWidget *parent = 0, const char *name = 0 );
	   protected:
	       bool eventFilter( QObject *obj, QEvent *ev );
	   private:
	       QTextEdit *textEdit;
	   };
	   MyMainWindow::MyMainWindow( QWidget *parent, const char *name )
	       : QMainWindow( parent, name )
	   {
	       textEdit = new QTextEdit( this );
	       setCentralWidget( textEdit );
	       textEdit->installEventFilter( this );
	   }
	   bool MyMainWindow::eventFilter( QObject *obj, QEvent *ev )
	   {
	       if ( obj == textEdit ) {
		   if ( e->type() == QEvent::KeyPress ) {
		       QKeyEvent *k = (QKeyEvent*)ev;
		       qDebug( "Ate key press %d", k->key() );
		       return TRUE;
		   } else {
		       return FALSE;
		   }
	       } else {
		   // pass the event on to the parent class
		   return QMainWindow::eventFilter( obj, ev );
	       }
	   }

       Notice in the example above that unhandled events are passed to the
       base class's eventFilter() function, since the base class might have
       reimplemented eventFilter() for its own internal purposes.

       Warning: 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.

       See also installEventFilter().

       Reimplemented in QAccel, QScrollView, and QSpinBox.

bool QObject::highPriority () const
       Returns TRUE if the object is a high-priority object, or FALSE if it is
       a standard-priority object.

       High-priority objects are placed first in QObject's list of children on
       the assumption that they will be referenced very often.

bool QObject::inherits ( const char * clname ) const
       Returns TRUE if this object is an instance of a class that inherits
       clname, and clname inherits QObject; otherwise returns FALSE.

       A class is considered to inherit itself.

       Example:

	       QTimer *t = new QTimer;	       // QTimer inherits QObject
	       t->inherits( "QTimer" );	       // returns TRUE
	       t->inherits( "QObject" );       // returns TRUE
	       t->inherits( "QButton" );       // returns FALSE
	       // QScrollBar inherits QWidget and QRangeControl
	       QScrollBar *s = new QScrollBar( 0 );
	       s->inherits( "QWidget" );       // returns TRUE
	       s->inherits( "QRangeControl" ); // returns FALSE

       (QRangeControl is not a QObject.)

       See also isA() and metaObject().

       Examples:

void QObject::insertChild ( QObject * obj ) [virtual]
       Inserts an object obj into the list of child objects.

       Warning: 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 QWidget::reparent().

       See also removeChild() and QWidget::reparent().

void QObject::installEventFilter ( const QObject * filterObj )
       Installs an event filter filterObj on this object. For example:

	   monitoredObj->installEventFilter( filterObj );

       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 filterObj receives events via its
       eventFilter() function. The eventFilter() function must return TRUE if
       the event should be filtered, (i.e. stopped); otherwise it must return
       FALSE.

       If multiple event filters are installed on a single object, the filter
       that was installed last is activated first.

       Here's a KeyPressEater class that eats the key presses of its monitored
       objects:

	   class KeyPressEater : public QObject
	   {
	       ...
	   protected:
	       bool eventFilter( QObject *o, QEvent *e );
	   };
	   bool KeyPressEater::eventFilter( QObject *o, QEvent *e )
	   {
	       if ( e->type() == QEvent::KeyPress ) {
		   // special processing for key press
		   QKeyEvent *k = (QKeyEvent *)e;
		   qDebug( "Ate key press %d", k->key() );
		   return TRUE; // eat event
	       } else {
		   // standard event processing
		   return FALSE;
	       }
	   }

       And here's how to install it on two widgets:

	       KeyPressEater *keyPressEater = new KeyPressEater( this );
	       QPushButton *pushButton = new QPushButton( this );
	       QListView *listView = new QListView( this );
	       pushButton->installEventFilter( keyPressEater );
	       listView->installEventFilter( keyPressEater );

       The QAccel class, for example, uses this technique to intercept
       accelerator key presses.

       Warning: If you delete the receiver object in your eventFilter()
       function, be sure to return TRUE. If you return FALSE, Qt sends the
       event to the deleted object and the program will crash.

       See also removeEventFilter(), eventFilter(), and event().

bool QObject::isA ( const char * clname ) const
       Returns TRUE if this object is an instance of the class clname;
       otherwise returns FALSE.

       Example:

	   QTimer *t = new QTimer; // QTimer inherits QObject
	   t->isA( "QTimer" );	   // returns TRUE
	   t->isA( "QObject" );	   // returns FALSE

       See also inherits() and metaObject().

bool QObject::isWidgetType () const
       Returns TRUE if the object is a widget; otherwise returns FALSE.

       Calling this function is equivalent to calling inherits("QWidget"),
       except that it is much faster.

void QObject::killTimer ( int id )
       Kills the timer with timer identifier, id.

       The timer identifier is returned by startTimer() when a timer event is
       started.

       See also timerEvent(), startTimer(), and killTimers().

void QObject::killTimers ()
       Kills all timers that this object has started.

       Warning: 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 QTimer or
       perhaps killTimer().

       See also timerEvent(), startTimer(), and killTimer().

QMetaObject * QObject::metaObject () const [virtual]
       Returns a pointer to the meta object of this object.

       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 Q_OBJECT macro will also have a meta object.

       The meta object information is required by the signal/slot connection
       mechanism and the property system. The functions isA() and inherits()
       also make use of the meta object.

const char * QObject::name () const
       Returns the name of this object. See the "name" property for details.

const char * QObject::name ( const char * defaultName ) const
       This is an overloaded member function, provided for convenience. It
       behaves essentially like the above function.

       Returns the name of this object, or defaultName if the object does not
       have a name.

QCString QObject::normalizeSignalSlot ( const char * signalSlot ) [static
       protected]
       Normlizes the signal or slot definition signalSlot by removing
       unnecessary whitespace.

const QObjectList * QObject::objectTrees () [static]
       Returns a pointer to the list of all object trees (their root objects),
       or 0 if there are no objects.

       The QObjectList class is defined in the qobjectlist.h header file.

       The most recent root object created is the first object in the list and
       the first root object added is the last object in the list.

       See also children(), parent(), insertChild(), and removeChild().

QObject * QObject::parent () const
       Returns a pointer to the parent object.

       See also children().

QVariant QObject::property ( const char * name ) const [virtual]
       Returns the value of the object's name property.

       If no such property exists, the returned variant is invalid.

       Information about all available properties are provided through the
       metaObject().

       See also setProperty(), QVariant::isValid(), metaObject(),
       QMetaObject::propertyNames(), and QMetaObject::property().

       Example: qutlook/centralwidget.cpp.

QObjectList * QObject::queryList ( const char * inheritsClass = 0, const char
       * objName = 0, bool regexpMatch = TRUE, bool recursiveSearch = TRUE )
       const
       Searches the children and optionally grandchildren of this object, and
       returns a list of those objects that are named or that match objName
       and inherit inheritsClass. If inheritsClass is 0 (the default), all
       classes match. If objName is 0 (the default), all object names match.

       If regexpMatch is TRUE (the default), objName is a regular expression
       that the objects's names must match. The syntax is that of a QRegExp.
       If regexpMatch is FALSE, objName is a string and object names must
       match it exactly.

       Note that inheritsClass uses single inheritance from QObject, the way
       inherits() does. According to inherits(), QMenuBar inherits QWidget but
       not QMenuData. This does not quite match reality, but is the best that
       can be done on the wide variety of compilers Qt supports.

       Finally, if recursiveSearch is TRUE (the default), queryList() searches
       nth-generation as well as first-generation children.

       If all this seems a bit complex for your needs, the simpler child()
       function may be what you want.

       This somewhat contrived example disables all the buttons in this
       window:

	   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

       The QObjectList class is defined in the qobjectlist.h header file.

       Warning: 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).

       See also child(), children(), parent(), inherits(), name, and QRegExp.

void QObject::removeChild ( QObject * obj ) [virtual]
       Removes the child object obj from the list of children.

       Warning: This function will not remove a child widget from the screen.
       It will only remove it from the parent widget's list of children.

       See also insertChild() and QWidget::reparent().

void QObject::removeEventFilter ( const QObject * obj )
       Removes an event filter object obj from this object. The request is
       ignored if such an event filter has not been installed.

       All event filters for this object are automatically removed when this
       object is destroyed.

       It is always safe to remove an event filter, even during event filter
       activation (i.e. from the eventFilter() function).

       See also installEventFilter(), eventFilter(), and event().

const QObject * QObject::sender () [protected]
       Returns a pointer to the object that sent the signal, if called in a
       slot activated by a signal; otherwise it returns 0. The pointer is
       valid only during the execution of the slot that calls this function.

       The pointer returned by this function becomes invalid if the sender is
       destroyed, or if the slot is disconnected from the sender's signal.

       Warning: This function violates the object-oriented principle of
       modularity. However, getting access to the sender might be useful when
       many signals are connected to a single slot. The sender is undefined if
       the slot is called as a normal C++ function.

void QObject::setName ( const char * name ) [virtual]
       Sets the object's name to name.

bool QObject::setProperty ( const char * name, const QVariant & value )
       [virtual]
       Sets the value of the object's name property to value.

       Returns TRUE if the operation was successful; otherwise returns FALSE.

       Information about all available properties is provided through the
       metaObject().

       See also property(), metaObject(), QMetaObject::propertyNames(), and
       QMetaObject::property().

       Example: qutlook/centralwidget.cpp.

bool QObject::signalsBlocked () const
       Returns TRUE if signals are blocked; otherwise returns FALSE.

       Signals are not blocked by default.

       See also blockSignals().

int QObject::startTimer ( int interval )
       Starts a timer and returns a timer identifier, or returns zero if it
       could not start a timer.

       A timer event will occur every interval milliseconds until killTimer()
       or killTimers() is called. If interval is 0, then the timer event
       occurs once every time there are no more window system events to
       process.

       The virtual timerEvent() function is called with the QTimerEvent event
       parameter class when a timer event occurs. Reimplement this function to
       get timer events.

       If multiple timers are running, the QTimerEvent::timerId() can be used
       to find out which timer was activated.

       Example:

	   class MyObject : public QObject
	   {
	       Q_OBJECT
	   public:
	       MyObject( QObject *parent = 0, const char *name = 0 );
	   protected:
	       void timerEvent( QTimerEvent * );
	   };
	   MyObject::MyObject( QObject *parent, const char *name )
	       : QObject( parent, name )
	   {
	       startTimer( 50 );    // 50-millisecond timer
	       startTimer( 1000 );  // 1-second timer
	       startTimer( 60000 ); // 1-minute timer
	   }
	   void MyObject::timerEvent( QTimerEvent *e )
	   {
	       qDebug( "timer event, id %d", e->timerId() );
	   }

       Note that QTimer's accuracy depends on the underlying operating system
       and hardware. Most platforms support an accuracy of 20 ms; some provide
       more. If Qt is unable to deliver the requested number of timer clicks,
       it will silently discard some.

       The QTimer class provides a high-level programming interface with one-
       shot timers and timer signals instead of events.

       See also timerEvent(), killTimer(), killTimers(), QEventLoop::awake(),
       and QEventLoop::aboutToBlock().

void QObject::timerEvent ( QTimerEvent * ) [virtual protected]
       This event handler can be reimplemented in a subclass to receive timer
       events for the object.

       QTimer provides a higher-level interface to the timer functionality,
       and also more general information about timers.

       See also startTimer(), killTimer(), killTimers(), and event().

       Examples:

QString QObject::tr ( const char * sourceText, const char * comment ) [static]

       Returns a translated version of sourceText, or sourceText itself if
       there is no appropriate translated version. The translation context is
       QObject with comment (0 by default). All QObject subclasses using the
       Q_OBJECT macro automatically have a reimplementation of this function
       with the subclass name as context.

       Warning: This method is reentrant only if all translators are installed
       before calling this method. Installing or removing translators while
       performing translations is not supported. Doing so will probably result
       in crashes or other undesirable behavior.

       See also trUtf8(), QApplication::translate(), and Internationalization
       with Qt.

       Example: network/networkprotocol/view.cpp.

QString QObject::trUtf8 ( const char * sourceText, const char * comment )
       [static]
       Returns a translated version of sourceText, or
       QString::fromUtf8(sourceText) if there is no appropriate version. It is
       otherwise identical to tr(sourceText, comment).

       Warning: This method is reentrant only if all translators are installed
       before calling this method. Installing or removing translators while
       performing translations is not supported. Doing so will probably result
       in crashes or other undesirable behavior.

       See also tr() and QApplication::translate().

   Property Documentation
QCString name
       This property holds the name of this object.

       You can find an object by name (and type) using child(). You can find a
       set of objects with queryList().

       The object name is set by the constructor or by the setName() function.
       The object name is not very useful in the current version of Qt, but
       will become increasingly important in the future.

       If the object does not have a name, the name() function returns"
       unnamed", so printf() (used in qDebug()) 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 ).

	       qDebug( "MyClass::setPrecision(): (%s) invalid precision %f",
		       name(), newPrecision );

       See also className(), child(), and queryList().

       Set this property's value with setName() and get this property's value
       with name().

RELATED FUNCTION DOCUMENTATION
void * qt_find_obj_child ( QObject * parent, const char * type, const char *
       name )
       Returns a pointer to the object named name that inherits type and with
       a given parent.

       Returns 0 if there is no such child.

	       QListBox *c = (QListBox *) qt_find_obj_child( myWidget, "QListBox",
							     "my list box" );
	       if ( c )
		   c->insertItem( "another string" );

SEE ALSO
       http://doc.trolltech.com/qobject.html
       http://www.trolltech.com/faq/tech.html

COPYRIGHT
       Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com.  See the
       license file included in the distribution for a complete license
       statement.

AUTHOR
       Generated automatically from the source code.

BUGS
       If you find a bug in Qt, please report it as described in
       http://doc.trolltech.com/bughowto.html.	Good bug reports help us to
       help you. Thank you.

       The definitive Qt documentation is provided in HTML format; it is
       located at $QTDIR/doc/html and can be read using Qt Assistant or with a
       web browser. This man page is provided as a convenience for those users
       who prefer man pages, although this format is not officially supported
       by Trolltech.

       If you find errors in this manual page, please report them to qt-
       bugs@trolltech.com.  Please include the name of the manual page
       (qobject.3qt) and the Qt version (3.3.8).

Trolltech AS			2 February 2007			  QObject(3qt)
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