/**************************************************************************** ** ** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). ** All rights reserved. ** Contact: Nokia Corporation (qt-info@nokia.com) ** ** This file is part of the QtCore module of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:LGPL$ ** No Commercial Usage ** This file contains pre-release code and may not be distributed. ** You may use this file in accordance with the terms and conditions ** contained in the Technology Preview License Agreement accompanying ** this package. ** ** GNU Lesser General Public License Usage ** Alternatively, this file may be used under the terms of the GNU Lesser ** General Public License version 2.1 as published by the Free Software ** Foundation and appearing in the file LICENSE.LGPL included in the ** packaging of this file. Please review the following information to ** ensure the GNU Lesser General Public License version 2.1 requirements ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. ** ** In addition, as a special exception, Nokia gives you certain additional ** rights. These rights are described in the Nokia Qt LGPL Exception ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. ** ** If you have questions regarding the use of this file, please contact ** Nokia at qt-info@nokia.com. ** ** ** ** ** ** ** ** ** $QT_END_LICENSE$ ** ****************************************************************************/ #include "qobject.h" #include "qobject_p.h" #include "qmetaobject_p.h" #include "qabstracteventdispatcher.h" #include "qcoreapplication.h" #include "qcoreapplication_p.h" #include "qvariant.h" #include "qmetaobject.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include QT_BEGIN_NAMESPACE static int DIRECT_CONNECTION_ONLY = 0; static int *queuedConnectionTypes(const QList &typeNames) { int *types = new int [typeNames.count() + 1]; Q_CHECK_PTR(types); for (int i = 0; i < typeNames.count(); ++i) { const QByteArray typeName = typeNames.at(i); if (typeName.endsWith('*')) types[i] = QMetaType::VoidStar; else types[i] = QMetaType::type(typeName); if (!types[i]) { qWarning("QObject::connect: Cannot queue arguments of type '%s'\n" "(Make sure '%s' is registered using qRegisterMetaType().)", typeName.constData(), typeName.constData()); delete [] types; return 0; } } types[typeNames.count()] = 0; return types; } static QBasicAtomicPointer signalSlotMutexes = Q_BASIC_ATOMIC_INITIALIZER(0); static QBasicAtomicInt objectCount = Q_BASIC_ATOMIC_INITIALIZER(0); /** \internal * mutex to be locked when accessing the connectionlists or the senders list */ static inline QMutex *signalSlotLock(const QObject *o) { if (!signalSlotMutexes) { QMutexPool *mp = new QMutexPool; if (!signalSlotMutexes.testAndSetOrdered(0, mp)) { delete mp; } } return signalSlotMutexes->get(o); } extern "C" Q_CORE_EXPORT void qt_addObject(QObject *) { objectCount.ref(); } extern "C" Q_CORE_EXPORT void qt_removeObject(QObject *) { if(!objectCount.deref()) { QMutexPool *old = signalSlotMutexes.fetchAndStoreAcquire(0); delete old; } } void (*QAbstractDeclarativeData::destroyed)(QAbstractDeclarativeData *, QObject *) = 0; void (*QAbstractDeclarativeData::parentChanged)(QAbstractDeclarativeData *, QObject *, QObject *) = 0; void (*QAbstractDeclarativeData::objectNameChanged)(QAbstractDeclarativeData *, QObject *) = 0; QObjectData::~QObjectData() {} QObjectPrivate::QObjectPrivate(int version) : threadData(0), connectionLists(0), senders(0), currentSender(0), currentChildBeingDeleted(0) { if (version != QObjectPrivateVersion) qFatal("Cannot mix incompatible Qt library (version 0x%x) with this library (version 0x%x)", version, QObjectPrivateVersion); // QObjectData initialization q_ptr = 0; parent = 0; // no parent yet. It is set by setParent() isWidget = false; // assume not a widget object pendTimer = false; // no timers yet blockSig = false; // not blocking signals wasDeleted = false; // double-delete catcher sendChildEvents = true; // if we should send ChildInsert and ChildRemove events to parent receiveChildEvents = true; postedEvents = 0; extraData = 0; connectedSignals[0] = connectedSignals[1] = 0; inThreadChangeEvent = false; #ifdef QT_JAMBI_BUILD inEventHandler = false; deleteWatch = 0; #endif metaObject = 0; hasGuards = false; } QObjectPrivate::~QObjectPrivate() { if (pendTimer) { // unregister pending timers if (threadData->eventDispatcher) threadData->eventDispatcher->unregisterTimers(q_ptr); } if (postedEvents) QCoreApplication::removePostedEvents(q_ptr, 0); threadData->deref(); delete static_cast(metaObject); #ifdef QT_JAMBI_BUILD if (deleteWatch) *deleteWatch = 1; #endif #ifndef QT_NO_USERDATA if (extraData) qDeleteAll(extraData->userData); delete extraData; #endif } #ifdef QT_JAMBI_BUILD int *QObjectPrivate::setDeleteWatch(QObjectPrivate *d, int *w) { int *old = d->deleteWatch; d->deleteWatch = w; return old; } void QObjectPrivate::resetDeleteWatch(QObjectPrivate *d, int *oldWatch, int deleteWatch) { if (!deleteWatch) d->deleteWatch = oldWatch; if (oldWatch) *oldWatch = deleteWatch; } #endif #ifdef QT3_SUPPORT void QObjectPrivate::sendPendingChildInsertedEvents() { Q_Q(QObject); for (int i = 0; i < pendingChildInsertedEvents.size(); ++i) { QObject *c = pendingChildInsertedEvents.at(i).data(); if (!c || c->parent() != q) continue; QChildEvent childEvent(QEvent::ChildInserted, c); QCoreApplication::sendEvent(q, &childEvent); } pendingChildInsertedEvents.clear(); } #endif /*!\internal For a given metaobject, compute the signal offset, and the method offset (including signals) */ static void computeOffsets(const QMetaObject *metaobject, int *signalOffset, int *methodOffset) { *signalOffset = *methodOffset = 0; const QMetaObject *m = metaobject->d.superdata; while (m) { const QMetaObjectPrivate *d = QMetaObjectPrivate::get(m); *methodOffset += d->methodCount; *signalOffset += (d->revision >= 4) ? d->signalCount : d->methodCount; /*Before Qt 4.6 (revision 4), the signalCount information was not generated by moc. so for compatibility we consider all the method as slot for old moc output*/ m = m->d.superdata; } } /* This vector contains the all connections from an object. Each object may have one vector containing the lists of connections for a given signal. The index in the vector correspond to the signal index. The signal index is the one returned by QObjectPrivate::signalIndex (not QMetaObject::indexOfSignal). Negative index means connections to all signals. This vector is protected by the object mutex (signalSlotMutexes()) Each Connection is also part of a 'senders' linked list. The mutex of the receiver must be locked when touching the pointers of this linked list. */ class QObjectConnectionListVector : public QVector { public: bool orphaned; //the QObject owner of this vector has been destroyed while the vector was inUse bool dirty; //some Connection have been disconnected (their receiver is 0) but not removed from the list yet int inUse; //number of functions that are currently accessing this object or its connections QObjectPrivate::ConnectionList allsignals; QObjectConnectionListVector() : QVector(), orphaned(false), dirty(false), inUse(0) { } const QObjectPrivate::ConnectionList &at(int at) const { if (at < 0) return allsignals; return QVector::at(at); } QObjectPrivate::ConnectionList &operator[](int at) { if (at < 0) return allsignals; return QVector::operator[](at); } }; // Used by QAccessibleWidget bool QObjectPrivate::isSender(const QObject *receiver, const char *signal) const { Q_Q(const QObject); int signal_index = signalIndex(signal); if (signal_index < 0) return false; QMutexLocker locker(signalSlotLock(q)); if (connectionLists) { if (signal_index < connectionLists->count()) { const QObjectPrivate::Connection *c = connectionLists->at(signal_index).first; while (c) { if (c->receiver == receiver) return true; c = c->nextConnectionList; } } } return false; } // Used by QAccessibleWidget QObjectList QObjectPrivate::receiverList(const char *signal) const { Q_Q(const QObject); QObjectList returnValue; int signal_index = signalIndex(signal); if (signal_index < 0) return returnValue; QMutexLocker locker(signalSlotLock(q)); if (connectionLists) { if (signal_index < connectionLists->count()) { const QObjectPrivate::Connection *c = connectionLists->at(signal_index).first; while (c) { if (c->receiver) returnValue << c->receiver; c = c->nextConnectionList; } } } return returnValue; } // Used by QAccessibleWidget QObjectList QObjectPrivate::senderList() const { QObjectList returnValue; QMutexLocker locker(signalSlotLock(q_func())); for (Connection *c = senders; c; c = c->next) returnValue << c->sender; return returnValue; } void QObjectPrivate::addConnection(int signal, Connection *c) { if (!connectionLists) connectionLists = new QObjectConnectionListVector(); if (signal >= connectionLists->count()) connectionLists->resize(signal + 1); ConnectionList &connectionList = (*connectionLists)[signal]; if (connectionList.last) { connectionList.last->nextConnectionList = c; } else { connectionList.first = c; } connectionList.last = c; cleanConnectionLists(); } void QObjectPrivate::cleanConnectionLists() { if (connectionLists->dirty && !connectionLists->inUse) { // remove broken connections for (int signal = -1; signal < connectionLists->count(); ++signal) { QObjectPrivate::ConnectionList &connectionList = (*connectionLists)[signal]; // Set to the last entry in the connection list that was *not* // deleted. This is needed to update the list's last pointer // at the end of the cleanup. QObjectPrivate::Connection *last = 0; QObjectPrivate::Connection **prev = &connectionList.first; QObjectPrivate::Connection *c = *prev; while (c) { if (c->receiver) { last = c; prev = &c->nextConnectionList; c = *prev; } else { QObjectPrivate::Connection *next = c->nextConnectionList; *prev = next; delete c; c = next; } } // Correct the connection list's last pointer. // As conectionList.last could equal last, this could be a noop connectionList.last = last; } connectionLists->dirty = false; } } typedef QMultiHash GuardHash; Q_GLOBAL_STATIC(GuardHash, guardHash) Q_GLOBAL_STATIC(QMutex, guardHashLock) /*!\internal */ void QMetaObject::addGuard(QObject **ptr) { if (!*ptr) return; GuardHash *hash = guardHash(); if (!hash) { *ptr = 0; return; } QMutexLocker locker(guardHashLock()); QObjectPrivate::get(*ptr)->hasGuards = true; hash->insert(*ptr, ptr); } /*!\internal */ void QMetaObject::removeGuard(QObject **ptr) { if (!*ptr) return; GuardHash *hash = guardHash(); /* check that the hash is empty - otherwise we might detach the shared_null hash, which will alloc, which is not nice */ if (!hash || hash->isEmpty()) return; QMutexLocker locker(guardHashLock()); if (!*ptr) //check again, under the lock return; GuardHash::iterator it = hash->find(*ptr); const GuardHash::iterator end = hash->end(); bool more = false; //if the QObject has more pointer attached to it. for (; it.key() == *ptr && it != end; ++it) { if (it.value() == ptr) { it = hash->erase(it); if (!more) more = (it != end && it.key() == *ptr); break; } more = true; } if (!more) QObjectPrivate::get(*ptr)->hasGuards = false; } /*!\internal */ void QMetaObject::changeGuard(QObject **ptr, QObject *o) { GuardHash *hash = guardHash(); if (!hash) { *ptr = 0; return; } QMutexLocker locker(guardHashLock()); if (o) { hash->insert(o, ptr); QObjectPrivate::get(o)->hasGuards = true; } if (*ptr) { bool more = false; //if the QObject has more pointer attached to it. GuardHash::iterator it = hash->find(*ptr); const GuardHash::iterator end = hash->end(); for (; it.key() == *ptr && it != end; ++it) { if (it.value() == ptr) { it = hash->erase(it); if (!more) more = (it != end && it.key() == *ptr); break; } more = true; } if (!more) QObjectPrivate::get(*ptr)->hasGuards = false; } *ptr = o; } /*! \internal */ void QObjectPrivate::clearGuards(QObject *object) { GuardHash *hash = 0; QMutex *mutex = 0; QT_TRY { hash = guardHash(); mutex = guardHashLock(); } QT_CATCH(const std::bad_alloc &) { // do nothing in case of OOM - code below is safe } /* check that the hash is empty - otherwise we might detach the shared_null hash, which will alloc, which is not nice */ if (hash && !hash->isEmpty()) { QMutexLocker locker(mutex); GuardHash::iterator it = hash->find(object); const GuardHash::iterator end = hash->end(); while (it.key() == object && it != end) { *it.value() = 0; it = hash->erase(it); } } } /*! \internal */ QMetaCallEvent::QMetaCallEvent(int id, const QObject *sender, int signalId, int nargs, int *types, void **args, QSemaphore *semaphore) : QEvent(MetaCall), id_(id), sender_(sender), signalId_(signalId), nargs_(nargs), types_(types), args_(args), semaphore_(semaphore) { } /*! \internal */ QMetaCallEvent::~QMetaCallEvent() { if (types_) { for (int i = 0; i < nargs_; ++i) { if (types_[i] && args_[i]) QMetaType::destroy(types_[i], args_[i]); } qFree(types_); qFree(args_); } #ifndef QT_NO_THREAD if (semaphore_) semaphore_->release(); #endif } /*! \internal */ int QMetaCallEvent::placeMetaCall(QObject *object) { return QMetaObject::metacall(object, QMetaObject::InvokeMetaMethod, id_, args_); } /*! \class QObject \brief The QObject class is the base class of all Qt objects. \ingroup objectmodel \reentrant QObject is the heart of the Qt \l{Object Model}. The central feature in this model is a very powerful mechanism for seamless object communication called \l{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 \l {Object Trees & Ownership} {object trees}. When you create a QObject with another object as parent, the object will automatically add itself to 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 findChild() or findChildren(). Every object has an objectName() and its class name can be found via the corresponding metaObject() (see QMetaObject::className()). You can determine whether the object's class inherits another class in the QObject inheritance hierarchy by using the inherits() function. When an object is deleted, it emits a destroyed() signal. You can catch this signal to avoid dangling references to QObjects. 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. Events are delivered in the thread in which the object was created; see \l{Thread Support in Qt} and thread() for details. Note that event processing is not done at all for QObjects with no thread affinity (thread() returns zero). Use the moveToThread() function to change the thread affinity for an object and its children (the object cannot be moved if it has a parent). 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 \l{moc}{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 strange behavior. All Qt widgets inherit QObject. The convenience function isWidgetType() returns whether an object is actually a widget. It is much faster than \l{qobject_cast()}{qobject_cast}(\e{obj}) or \e{obj}->\l{inherits()}{inherits}("QWidget"). Some QObject functions, e.g. children(), return a QObjectList. QObjectList is a typedef for QList. \target No copy constructor \section1 No copy constructor or assignment operator QObject has neither a copy constructor nor an assignment operator. This is by design. Actually, they are declared, but in a \c{private} section with the macro Q_DISABLE_COPY(). In fact, all Qt classes derived from QObject (direct or indirect) use this macro to declare their copy constructor and assignment operator to be private. The reasoning is found in the discussion on \l{Identity vs Value} {Identity vs Value} on the Qt \l{Object Model} page. The main consequence is that you should use pointers to QObject (or to your QObject subclass) where you might otherwise be tempted to use your QObject subclass as a value. For example, without a copy constructor, you can't use a subclass of QObject as the value to be stored in one of the container classes. You must store pointers. \section1 Auto-Connection Qt's meta-object system provides a mechanism to automatically connect signals and slots between QObject subclasses and their children. As long as objects are defined with suitable object names, and slots follow a simple naming convention, this connection can be performed at run-time by the QMetaObject::connectSlotsByName() function. \l uic generates code that invokes this function to enable auto-connection to be performed between widgets on forms created with \QD. More information about using auto-connection with \QD is given in the \l{Using a Designer UI File in Your Application} section of the \QD manual. \section1 Dynamic Properties From Qt 4.2, dynamic properties can be added to and removed from QObject instances at run-time. Dynamic properties do not need to be declared at compile-time, yet they provide the same advantages as static properties and are manipulated using the same API - using property() to read them and setProperty() to write them. From Qt 4.3, dynamic properties are supported by \l{Qt Designer's Widget Editing Mode#The Property Editor}{Qt Designer}, and both standard Qt widgets and user-created forms can be given dynamic properties. \section1 Internationalization (i18n) All QObject subclasses support Qt's translation features, making it possible to translate an application's user interface into different languages. To make user-visible text translatable, it must be wrapped in calls to the tr() function. This is explained in detail in the \l{Writing Source Code for Translation} document. \sa QMetaObject, QPointer, QObjectCleanupHandler, Q_DISABLE_COPY() \sa {Object Trees & Ownership} */ /*! \relates QObject Returns a pointer to the object named \a name that inherits \a type and with a given \a parent. Returns 0 if there is no such child. \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 0 */ void *qt_find_obj_child(QObject *parent, const char *type, const QString &name) { QObjectList list = parent->children(); if (list.size() == 0) return 0; for (int i = 0; i < list.size(); ++i) { QObject *obj = list.at(i); if (name == obj->objectName() && obj->inherits(type)) return obj; } return 0; } /***************************************************************************** QObject member functions *****************************************************************************/ // check the constructor's parent thread argument static bool check_parent_thread(QObject *parent, QThreadData *parentThreadData, QThreadData *currentThreadData) { if (parent && parentThreadData != currentThreadData) { QThread *parentThread = parentThreadData->thread; QThread *currentThread = currentThreadData->thread; qWarning("QObject: Cannot create children for a parent that is in a different thread.\n" "(Parent is %s(%p), parent's thread is %s(%p), current thread is %s(%p)", parent->metaObject()->className(), parent, parentThread ? parentThread->metaObject()->className() : "QThread", parentThread, currentThread ? currentThread->metaObject()->className() : "QThread", currentThread); return false; } return true; } /*! Constructs an object with parent object \a parent. The parent of an object may be viewed as the object's owner. For instance, a \l{QDialog}{dialog box} is the parent of the \gui OK and \gui Cancel buttons it contains. The destructor of a parent object destroys all child objects. Setting \a parent to 0 constructs an object with no parent. If the object is a widget, it will become a top-level window. \sa parent(), findChild(), findChildren() */ QObject::QObject(QObject *parent) : d_ptr(new QObjectPrivate) { Q_D(QObject); d_ptr->q_ptr = this; d->threadData = (parent && !parent->thread()) ? parent->d_func()->threadData : QThreadData::current(); d->threadData->ref(); if (parent) { QT_TRY { if (!check_parent_thread(parent, parent ? parent->d_func()->threadData : 0, d->threadData)) parent = 0; setParent(parent); } QT_CATCH(...) { d->threadData->deref(); QT_RETHROW; } } qt_addObject(this); } #ifdef QT3_SUPPORT /*! \overload QObject() \obsolete Creates a new QObject with the given \a parent and object \a name. */ QObject::QObject(QObject *parent, const char *name) : d_ptr(new QObjectPrivate) { Q_D(QObject); qt_addObject(d_ptr->q_ptr = this); d->threadData = (parent && !parent->thread()) ? parent->d_func()->threadData : QThreadData::current(); d->threadData->ref(); if (parent) { if (!check_parent_thread(parent, parent ? parent->d_func()->threadData : 0, d->threadData)) parent = 0; setParent(parent); } setObjectName(QString::fromAscii(name)); } #endif /*! \internal */ QObject::QObject(QObjectPrivate &dd, QObject *parent) : d_ptr(&dd) { Q_D(QObject); d_ptr->q_ptr = this; d->threadData = (parent && !parent->thread()) ? parent->d_func()->threadData : QThreadData::current(); d->threadData->ref(); if (parent) { QT_TRY { if (!check_parent_thread(parent, parent ? parent->d_func()->threadData : 0, d->threadData)) parent = 0; if (d->isWidget) { if (parent) { d->parent = parent; d->parent->d_func()->children.append(this); } // no events sent here, this is done at the end of the QWidget constructor } else { setParent(parent); } } QT_CATCH(...) { d->threadData->deref(); QT_RETHROW; } } qt_addObject(this); } /*! Destroys the object, deleting all its child objects. All signals to and from the object are automatically disconnected, and any pending posted events for the object are removed from the event queue. However, it is often safer to use deleteLater() rather than deleting a QObject subclass directly. \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 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 if it exists in a different thread than the one currently executing. Use deleteLater() instead, which will cause the event loop to delete the object after all pending events have been delivered to it. \sa deleteLater() */ QObject::~QObject() { Q_D(QObject); d->wasDeleted = true; d->blockSig = 0; // unblock signals so we always emit destroyed() if (d->hasGuards && !d->isWidget) { // set all QPointers for this object to zero - note that // ~QWidget() does this for us, so we don't have to do it twice QObjectPrivate::clearGuards(this); } if (d->sharedRefcount) { if (d->sharedRefcount->strongref > 0) { qWarning("QObject: shared QObject was deleted directly. The program is malformed and may crash."); // but continue deleting, it's too late to stop anyway } // indicate to all QWeakPointers that this QObject has now been deleted d->sharedRefcount->strongref = 0; if (!d->sharedRefcount->weakref.deref()) delete d->sharedRefcount; } if (d->isSignalConnected(0)) { QT_TRY { emit destroyed(this); } QT_CATCH(...) { // all the signal/slots connections are still in place - if we don't // quit now, we will crash pretty soon. qWarning("Detected an unexpected exception in ~QObject while emitting destroyed()."); QT_RETHROW; } } if (d->declarativeData) QAbstractDeclarativeData::destroyed(d->declarativeData, this); // set ref to zero to indicate that this object has been deleted if (d->currentSender != 0) d->currentSender->ref = 0; d->currentSender = 0; if (d->connectionLists || d->senders) { QMutex *signalSlotMutex = signalSlotLock(this); QMutexLocker locker(signalSlotMutex); // disconnect all receivers if (d->connectionLists) { ++d->connectionLists->inUse; int connectionListsCount = d->connectionLists->count(); for (int signal = -1; signal < connectionListsCount; ++signal) { QObjectPrivate::ConnectionList &connectionList = (*d->connectionLists)[signal]; while (QObjectPrivate::Connection *c = connectionList.first) { if (!c->receiver) { connectionList.first = c->nextConnectionList; delete c; continue; } QMutex *m = signalSlotLock(c->receiver); bool needToUnlock = QOrderedMutexLocker::relock(signalSlotMutex, m); if (c->receiver) { *c->prev = c->next; if (c->next) c->next->prev = c->prev; } if (needToUnlock) m->unlockInline(); connectionList.first = c->nextConnectionList; delete c; } } if (!--d->connectionLists->inUse) { delete d->connectionLists; } else { d->connectionLists->orphaned = true; } d->connectionLists = 0; } // disconnect all senders QObjectPrivate::Connection *node = d->senders; while (node) { QObject *sender = node->sender; QMutex *m = signalSlotLock(sender); node->prev = &node; bool needToUnlock = QOrderedMutexLocker::relock(signalSlotMutex, m); //the node has maybe been removed while the mutex was unlocked in relock? if (!node || node->sender != sender) { m->unlockInline(); continue; } node->receiver = 0; QObjectConnectionListVector *senderLists = sender->d_func()->connectionLists; if (senderLists) senderLists->dirty = true; node = node->next; if (needToUnlock) m->unlockInline(); } } if (!d->children.isEmpty()) d->deleteChildren(); qt_removeObject(this); if (d->parent) // remove it from parent object d->setParent_helper(0); #ifdef QT_JAMBI_BUILD if (d->inEventHandler) { qWarning("QObject: Do not delete object, '%s', during its event handler!", objectName().isNull() ? "unnamed" : qPrintable(objectName())); } #endif } QObjectPrivate::Connection::~Connection() { if (argumentTypes != &DIRECT_CONNECTION_ONLY) delete [] static_cast(argumentTypes); } /*! \fn QMetaObject *QObject::metaObject() const 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 QObject subclass that contains the Q_OBJECT macro will have a meta-object. The meta-object information is required by the signal/slot connection mechanism and the property system. The inherits() function also makes use of the meta-object. If you have no pointer to an actual object instance but still want to access the meta-object of a class, you can use \l staticMetaObject. Example: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 1 \sa staticMetaObject */ /*! \variable QObject::staticMetaObject This variable stores the meta-object for the class. 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 inherits() function also makes use of the meta-object. If you have a pointer to an object, you can use metaObject() to retrieve the meta-object associated with that object. Example: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 2 \sa metaObject() */ /*! \fn T *qobject_cast(QObject *object) \relates QObject Returns the given \a object cast to type T if the object is of type T (or of a subclass); otherwise returns 0. If \a object is 0 then it will also return 0. The class T must inherit (directly or indirectly) QObject and be declared with the \l Q_OBJECT macro. A class is considered to inherit itself. Example: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 3 The qobject_cast() function behaves similarly to the standard C++ \c dynamic_cast(), with the advantages that it doesn't require RTTI support and it works across dynamic library boundaries. qobject_cast() can also be used in conjunction with interfaces; see the \l{tools/plugandpaint}{Plug & Paint} example for details. \warning If T isn't declared with the Q_OBJECT macro, this function's return value is undefined. \sa QObject::inherits() */ /*! \fn bool QObject::inherits(const char *className) const Returns true if this object is an instance of a class that inherits \a className or a QObject subclass that inherits \a className; otherwise returns false. A class is considered to inherit itself. Example: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 4 If you need to determine whether an object is an instance of a particular class for the purpose of casting it, consider using qobject_cast(object) instead. \sa metaObject(), qobject_cast() */ /*! \property QObject::objectName \brief the name of this object You can find an object by name (and type) using findChild(). You can find a set of objects with findChildren(). \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 5 By default, this property contains an empty string. \sa metaObject(), QMetaObject::className() */ QString QObject::objectName() const { Q_D(const QObject); return d->objectName; } /* Sets the object's name to \a name. */ void QObject::setObjectName(const QString &name) { Q_D(QObject); bool objectNameChanged = d->declarativeData && d->objectName != name; d->objectName = name; if (objectNameChanged) d->declarativeData->objectNameChanged(d->declarativeData, this); } #ifdef QT3_SUPPORT /*! \internal QObject::child is compat but needs to call itself recursively, that's why we need this helper. */ static QObject *qChildHelper(const char *objName, const char *inheritsClass, bool recursiveSearch, const QObjectList &children) { if (children.isEmpty()) return 0; bool onlyWidgets = (inheritsClass && qstrcmp(inheritsClass, "QWidget") == 0); const QLatin1String oName(objName); for (int i = 0; i < children.size(); ++i) { QObject *obj = children.at(i); if (onlyWidgets) { if (obj->isWidgetType() && (!objName || obj->objectName() == oName)) return obj; } else if ((!inheritsClass || obj->inherits(inheritsClass)) && (!objName || obj->objectName() == oName)) return obj; if (recursiveSearch && (obj = qChildHelper(objName, inheritsClass, recursiveSearch, obj->children()))) return obj; } return 0; } /*! Searches the children and optionally grandchildren of this object, and returns a child that is called \a objName that inherits \a inheritsClass. If \a inheritsClass is 0 (the default), any class matches. If \a 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 returned. */ QObject* QObject::child(const char *objName, const char *inheritsClass, bool recursiveSearch) const { Q_D(const QObject); return qChildHelper(objName, inheritsClass, recursiveSearch, d->children); } #endif /*! \fn 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. */ /*! This virtual function receives events to an object and should return true if the event \a e was recognized and processed. The event() function can be reimplemented to customize the behavior of an object. \sa installEventFilter(), timerEvent(), QApplication::sendEvent(), QApplication::postEvent(), QWidget::event() */ bool QObject::event(QEvent *e) { switch (e->type()) { case QEvent::Timer: timerEvent((QTimerEvent*)e); break; #ifdef QT3_SUPPORT case QEvent::ChildInsertedRequest: d_func()->sendPendingChildInsertedEvents(); break; #endif case QEvent::ChildAdded: case QEvent::ChildPolished: #ifdef QT3_SUPPORT case QEvent::ChildInserted: #endif case QEvent::ChildRemoved: childEvent((QChildEvent*)e); break; case QEvent::DeferredDelete: qDeleteInEventHandler(this); break; case QEvent::MetaCall: { #ifdef QT_JAMBI_BUILD d_func()->inEventHandler = false; #endif QMetaCallEvent *mce = static_cast(e); QObjectPrivate::Sender currentSender; currentSender.sender = const_cast(mce->sender()); currentSender.signal = mce->signalId(); currentSender.ref = 1; QObjectPrivate::Sender * const previousSender = QObjectPrivate::setCurrentSender(this, ¤tSender); #if defined(QT_NO_EXCEPTIONS) mce->placeMetaCall(this); #else QT_TRY { mce->placeMetaCall(this); } QT_CATCH(...) { QObjectPrivate::resetCurrentSender(this, ¤tSender, previousSender); QT_RETHROW; } #endif QObjectPrivate::resetCurrentSender(this, ¤tSender, previousSender); break; } case QEvent::ThreadChange: { Q_D(QObject); QThreadData *threadData = d->threadData; QAbstractEventDispatcher *eventDispatcher = threadData->eventDispatcher; if (eventDispatcher) { QList > timers = eventDispatcher->registeredTimers(this); if (!timers.isEmpty()) { // set inThreadChangeEvent to true to tell the dispatcher not to release out timer ids // back to the pool (since the timer ids are moving to a new thread). d->inThreadChangeEvent = true; eventDispatcher->unregisterTimers(this); d->inThreadChangeEvent = false; QMetaObject::invokeMethod(this, "_q_reregisterTimers", Qt::QueuedConnection, Q_ARG(void*, (new QList >(timers)))); } } break; } default: if (e->type() >= QEvent::User) { customEvent(e); break; } return false; } return true; } /*! \fn void QObject::timerEvent(QTimerEvent *event) 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. The timer event is passed in the \a event parameter. \sa startTimer(), killTimer(), event() */ void QObject::timerEvent(QTimerEvent *) { } /*! This event handler can be reimplemented in a subclass to receive child events. The event is passed in the \a event parameter. QEvent::ChildAdded and QEvent::ChildRemoved events are sent to objects when children are added or removed. In both cases you can only rely on the child being a QObject, or if isWidgetType() returns true, a QWidget. (This is because, in the \l{QEvent::ChildAdded}{ChildAdded} case, the child is not yet fully constructed, and in the \l{QEvent::ChildRemoved}{ChildRemoved} case it might have been destructed already). QEvent::ChildPolished events are sent to widgets when children are polished, or when polished children are added. If you receive a child polished event, the child's construction is usually completed. However, this is not guaranteed, and multiple polish events may be delivered during the execution of a widget's constructor. For every child widget, you receive one \l{QEvent::ChildAdded}{ChildAdded} event, zero or more \l{QEvent::ChildPolished}{ChildPolished} events, and one \l{QEvent::ChildRemoved}{ChildRemoved} event. The \l{QEvent::ChildPolished}{ChildPolished} event is omitted if a child is removed immediately after it is added. If a child is polished several times during construction and destruction, you may receive several child polished events for the same child, each time with a different virtual table. \sa event() */ void QObject::childEvent(QChildEvent * /* event */) { } /*! 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 QEvent::User item of the QEvent::Type enum, and is typically a QEvent subclass. The event is passed in the \a event parameter. \sa event(), QEvent */ void QObject::customEvent(QEvent * /* event */) { } /*! Filters events if this object has been installed as an event filter for the \a watched object. In your reimplementation of this function, if you want to filter the \a event out, i.e. stop it being handled further, return true; otherwise return false. Example: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 6 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. \sa installEventFilter() */ bool QObject::eventFilter(QObject * /* watched */, QEvent * /* event */) { return false; } /*! \fn bool QObject::signalsBlocked() const Returns true if signals are blocked; otherwise returns false. Signals are not blocked by default. \sa blockSignals() */ /*! If \a block is true, signals emitted by this object are blocked (i.e., emitting a signal will not invoke anything connected to it). If \a block is false, no such blocking will occur. The return value is the previous value of signalsBlocked(). Note that the destroyed() signal will be emitted even if the signals for this object have been blocked. \sa signalsBlocked() */ bool QObject::blockSignals(bool block) { Q_D(QObject); bool previous = d->blockSig; d->blockSig = block; return previous; } /*! Returns the thread in which the object lives. \sa moveToThread() */ QThread *QObject::thread() const { return d_func()->threadData->thread; } /*! Changes the thread affinity for this object and its children. The object cannot be moved if it has a parent. Event processing will continue in the \a targetThread. To move an object to the main thread, use QApplication::instance() to retrieve a pointer to the current application, and then use QApplication::thread() to retrieve the thread in which the application lives. For example: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 7 If \a targetThread is zero, all event processing for this object and its children stops. Note that all active timers for the object will be reset. The timers are first stopped in the current thread and restarted (with the same interval) in the \a targetThread. As a result, constantly moving an object between threads can postpone timer events indefinitely. A QEvent::ThreadChange event is sent to this object just before the thread affinity is changed. You can handle this event to perform any special processing. Note that any new events that are posted to this object will be handled in the \a targetThread. \warning This function is \e not thread-safe; the current thread must be same as the current thread affinity. In other words, this function can only "push" an object from the current thread to another thread, it cannot "pull" an object from any arbitrary thread to the current thread. \sa thread() */ void QObject::moveToThread(QThread *targetThread) { Q_D(QObject); if (d->threadData->thread == targetThread) { // object is already in this thread return; } if (d->parent != 0) { qWarning("QObject::moveToThread: Cannot move objects with a parent"); return; } if (d->isWidget) { qWarning("QObject::moveToThread: Widgets cannot be moved to a new thread"); return; } QThreadData *currentData = QThreadData::current(); QThreadData *targetData = targetThread ? QThreadData::get2(targetThread) : new QThreadData(0); if (d->threadData->thread == 0 && currentData == targetData) { // one exception to the rule: we allow moving objects with no thread affinity to the current thread currentData = d->threadData; } else if (d->threadData != currentData) { qWarning("QObject::moveToThread: Current thread (%p) is not the object's thread (%p).\n" "Cannot move to target thread (%p)\n", currentData->thread, d->threadData->thread, targetData->thread); #ifdef Q_WS_MAC qWarning("On Mac OS X, you might be loading two sets of Qt binaries into the same process. " "Check that all plugins are compiled against the right Qt binaries. Export " "DYLD_PRINT_LIBRARIES=1 and check that only one set of binaries are being loaded."); #endif return; } // prepare to move d->moveToThread_helper(); QOrderedMutexLocker locker(¤tData->postEventList.mutex, &targetData->postEventList.mutex); // keep currentData alive (since we've got it locked) currentData->ref(); // move the object d_func()->setThreadData_helper(currentData, targetData); locker.unlock(); // now currentData can commit suicide if it wants to currentData->deref(); } void QObjectPrivate::moveToThread_helper() { Q_Q(QObject); QEvent e(QEvent::ThreadChange); QCoreApplication::sendEvent(q, &e); for (int i = 0; i < children.size(); ++i) { QObject *child = children.at(i); child->d_func()->moveToThread_helper(); } } void QObjectPrivate::setThreadData_helper(QThreadData *currentData, QThreadData *targetData) { Q_Q(QObject); // move posted events int eventsMoved = 0; for (int i = 0; i < currentData->postEventList.size(); ++i) { const QPostEvent &pe = currentData->postEventList.at(i); if (!pe.event) continue; if (pe.receiver == q) { // move this post event to the targetList targetData->postEventList.append(pe); const_cast(pe).event = 0; ++eventsMoved; } } if (eventsMoved > 0 && targetData->eventDispatcher) { targetData->canWait = false; targetData->eventDispatcher->wakeUp(); } // the current emitting thread shouldn't restore currentSender after calling moveToThread() if (currentSender) currentSender->ref = 0; currentSender = 0; #ifdef QT_JAMBI_BUILD // the current event thread also shouldn't restore the delete watch inEventHandler = false; if (deleteWatch) *deleteWatch = 1; deleteWatch = 0; #endif // set new thread data targetData->ref(); threadData->deref(); threadData = targetData; for (int i = 0; i < children.size(); ++i) { QObject *child = children.at(i); child->d_func()->setThreadData_helper(currentData, targetData); } } void QObjectPrivate::_q_reregisterTimers(void *pointer) { Q_Q(QObject); QList > *timerList = reinterpret_cast > *>(pointer); QAbstractEventDispatcher *eventDispatcher = threadData->eventDispatcher; for (int i = 0; i < timerList->size(); ++i) { const QPair &pair = timerList->at(i); eventDispatcher->registerTimer(pair.first, pair.second, q); } delete timerList; } // // The timer flag hasTimer is set when startTimer is called. // It is not reset when killing the timer because more than // one timer might be active. // /*! Starts a timer and returns a timer identifier, or returns zero if it could not start a timer. A timer event will occur every \a interval milliseconds until killTimer() is called. If \a 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: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 8 Note that QTimer's accuracy depends on the underlying operating system and hardware. Most platforms support an accuracy of 20 milliseconds; some provide more. If Qt is unable to deliver the requested number of timer events, it will silently discard some. The QTimer class provides a high-level programming interface with single-shot timers and timer signals instead of events. There is also a QBasicTimer class that is more lightweight than QTimer and less clumsy than using timer IDs directly. \sa timerEvent(), killTimer(), QTimer::singleShot() */ int QObject::startTimer(int interval) { Q_D(QObject); if (interval < 0) { qWarning("QObject::startTimer: QTimer cannot have a negative interval"); return 0; } d->pendTimer = true; // set timer flag if (!d->threadData->eventDispatcher) { qWarning("QObject::startTimer: QTimer can only be used with threads started with QThread"); return 0; } return d->threadData->eventDispatcher->registerTimer(interval, this); } /*! Kills the timer with timer identifier, \a id. The timer identifier is returned by startTimer() when a timer event is started. \sa timerEvent(), startTimer() */ void QObject::killTimer(int id) { Q_D(QObject); if (d->threadData->eventDispatcher) d->threadData->eventDispatcher->unregisterTimer(id); } /*! \fn QObject *QObject::parent() const Returns a pointer to the parent object. \sa children() */ /*! \fn const QObjectList &QObject::children() const Returns a list of child objects. The QObjectList class is defined in the \c{} header file as the following: \quotefromfile src/corelib/kernel/qobject.h \skipto /typedef .*QObjectList/ \printuntil QObjectList The first child added is the \l{QList::first()}{first} object in the list and the last child added is the \l{QList::last()}{last} object in the list, i.e. new children are appended at the end. Note that the list order changes when QWidget children are \l{QWidget::raise()}{raised} or \l{QWidget::lower()}{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. \sa findChild(), findChildren(), parent(), setParent() */ #ifdef QT3_SUPPORT static void objSearch(QObjectList &result, const QObjectList &list, const char *inheritsClass, bool onlyWidgets, const char *objName, QRegExp *rx, bool recurse) { for (int i = 0; i < list.size(); ++i) { QObject *obj = list.at(i); if (!obj) continue; bool ok = true; if (onlyWidgets) ok = obj->isWidgetType(); else if (inheritsClass && !obj->inherits(inheritsClass)) ok = false; if (ok) { if (objName) ok = (obj->objectName() == QLatin1String(objName)); #ifndef QT_NO_REGEXP else if (rx) ok = (rx->indexIn(obj->objectName()) != -1); #endif } if (ok) // match! result.append(obj); if (recurse) { QObjectList clist = obj->children(); if (!clist.isEmpty()) objSearch(result, clist, inheritsClass, onlyWidgets, objName, rx, recurse); } } } /*! \internal Searches the children and optionally grandchildren of this object, and returns a list of those objects that are named or that match \a objName and inherit \a inheritsClass. If \a inheritsClass is 0 (the default), all classes match. If \a objName is 0 (the default), all object names match. If \a regexpMatch is true (the default), \a objName is a regular expression that the objects's names must match. The syntax is that of a QRegExp. If \a regexpMatch is false, \a objName is a string and object names must match it exactly. Note that \a inheritsClass uses single inheritance from QObject, the way inherits() does. According to inherits(), QWidget inherits QObject but not QPaintDevice. This does not quite match reality, but is the best that can be done on the wide variety of compilers Qt supports. Finally, if \a recursiveSearch is true (the default), queryList() searches \e{n}th-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: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 9 \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). \sa child() children(), parent(), inherits(), objectName(), QRegExp */ QObjectList QObject::queryList(const char *inheritsClass, const char *objName, bool regexpMatch, bool recursiveSearch) const { Q_D(const QObject); QObjectList list; bool onlyWidgets = (inheritsClass && qstrcmp(inheritsClass, "QWidget") == 0); #ifndef QT_NO_REGEXP if (regexpMatch && objName) { // regexp matching QRegExp rx(QString::fromLatin1(objName)); objSearch(list, d->children, inheritsClass, onlyWidgets, 0, &rx, recursiveSearch); } else #endif { objSearch(list, d->children, inheritsClass, onlyWidgets, objName, 0, recursiveSearch); } return list; } #endif /*! \fn T *QObject::findChild(const QString &name) const Returns the child of this object that can be cast into type T and that is called \a name, or 0 if there is no such object. Omitting the \a name argument causes all object names to be matched. The search is performed recursively. If there is more than one child matching the search, the most direct ancestor is returned. If there are several direct ancestors, it is undefined which one will be returned. In that case, findChildren() should be used. This example returns a child \l{QPushButton} of \c{parentWidget} named \c{"button1"}: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 10 This example returns a \l{QListWidget} child of \c{parentWidget}: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 11 \sa findChildren() */ /*! \fn QList QObject::findChildren(const QString &name) const Returns all children of this object with the given \a name that can be cast to type T, or an empty list if there are no such objects. Omitting the \a name argument causes all object names to be matched. The search is performed recursively. The following example shows how to find a list of child \l{QWidget}s of the specified \c{parentWidget} named \c{widgetname}: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 12 This example returns all \c{QPushButton}s that are children of \c{parentWidget}: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 13 \sa findChild() */ /*! \fn QList QObject::findChildren(const QRegExp ®Exp) const \overload findChildren() Returns the children of this object that can be cast to type T and that have names matching the regular expression \a regExp, or an empty list if there are no such objects. The search is performed recursively. */ /*! \fn T qFindChild(const QObject *obj, const QString &name) \relates QObject \obsolete This function is equivalent to \a{obj}->\l{QObject::findChild()}{findChild}(\a name). \note This function was provided as a workaround for MSVC 6 which did not support member template functions. It is advised to use the other form in new code. \sa QObject::findChild() */ /*! \fn QList qFindChildren(const QObject *obj, const QString &name) \relates QObject \obsolete This function is equivalent to \a{obj}->\l{QObject::findChildren()}{findChildren}(\a name). \note This function was provided as a workaround for MSVC 6 which did not support member template functions. It is advised to use the other form in new code. \sa QObject::findChildren() */ /*! \fn QList qFindChildren(const QObject *obj, const QRegExp ®Exp) \relates QObject \overload qFindChildren() This function is equivalent to \a{obj}->\l{QObject::findChildren()}{findChildren}(\a regExp). \note This function was provided as a workaround for MSVC 6 which did not support member template functions. It is advised to use the other form in new code. \sa QObject::findChildren() */ /*! \internal \fn T qFindChild(const QObject *obj, const QString &name = QString(), T dummy = 0) \relates QObject \overload qFindChildren() This function is equivalent to \a{obj}->\l{QObject::findChild()}{findChild}(\a name). \note This function was provided as a workaround for MSVC 6 which did not support member template functions. It is advised to use the other form in new code. \sa QObject::findChild() */ /*! \internal \fn QList qFindChildren(const QObject *obj, const QString &name = QString(), T dummy = 0) \relates QObject \overload qFindChildren() This function is equivalent to \a{obj}->\l{QObject::findChildren()}{findChildren}(\a name). \note This function was provided as a workaround for MSVC 6 which did not support member template functions. It is advised to use the other form in new code. \sa QObject::findChildren() */ /*! \internal */ void qt_qFindChildren_helper(const QObject *parent, const QString &name, const QRegExp *re, const QMetaObject &mo, QList *list) { if (!parent || !list) return; const QObjectList &children = parent->children(); QObject *obj; for (int i = 0; i < children.size(); ++i) { obj = children.at(i); if (mo.cast(obj)) { if (re) { if (re->indexIn(obj->objectName()) != -1) list->append(obj); } else { if (name.isNull() || obj->objectName() == name) list->append(obj); } } qt_qFindChildren_helper(obj, name, re, mo, list); } } /*! \internal */ QObject *qt_qFindChild_helper(const QObject *parent, const QString &name, const QMetaObject &mo) { if (!parent) return 0; const QObjectList &children = parent->children(); QObject *obj; int i; for (i = 0; i < children.size(); ++i) { obj = children.at(i); if (mo.cast(obj) && (name.isNull() || obj->objectName() == name)) return obj; } for (i = 0; i < children.size(); ++i) { obj = qt_qFindChild_helper(children.at(i), name, mo); if (obj) return obj; } return 0; } /*! Makes the object a child of \a parent. \sa QWidget::setParent() */ void QObject::setParent(QObject *parent) { Q_D(QObject); Q_ASSERT(!d->isWidget); d->setParent_helper(parent); } void QObjectPrivate::deleteChildren() { const bool reallyWasDeleted = wasDeleted; wasDeleted = true; // delete children objects // don't use qDeleteAll as the destructor of the child might // delete siblings for (int i = 0; i < children.count(); ++i) { currentChildBeingDeleted = children.at(i); children[i] = 0; delete currentChildBeingDeleted; } children.clear(); currentChildBeingDeleted = 0; wasDeleted = reallyWasDeleted; } void QObjectPrivate::setParent_helper(QObject *o) { Q_Q(QObject); if (o == parent) return; if (parent) { QObjectPrivate *parentD = parent->d_func(); if (parentD->wasDeleted && wasDeleted && parentD->currentChildBeingDeleted == q) { // don't do anything since QObjectPrivate::deleteChildren() already // cleared our entry in parentD->children. } else { const int index = parentD->children.indexOf(q); if (parentD->wasDeleted) { parentD->children[index] = 0; } else { parentD->children.removeAt(index); if (sendChildEvents && parentD->receiveChildEvents) { QChildEvent e(QEvent::ChildRemoved, q); QCoreApplication::sendEvent(parent, &e); } } } } parent = o; if (parent) { // object hierarchies are constrained to a single thread if (threadData != parent->d_func()->threadData) { qWarning("QObject::setParent: Cannot set parent, new parent is in a different thread"); parent = 0; return; } parent->d_func()->children.append(q); if(sendChildEvents && parent->d_func()->receiveChildEvents) { if (!isWidget) { QChildEvent e(QEvent::ChildAdded, q); QCoreApplication::sendEvent(parent, &e); #ifdef QT3_SUPPORT if (QCoreApplicationPrivate::useQt3Support) { if (parent->d_func()->pendingChildInsertedEvents.isEmpty()) { QCoreApplication::postEvent(parent, new QEvent(QEvent::ChildInsertedRequest), Qt::HighEventPriority); } parent->d_func()->pendingChildInsertedEvents.append(q); } #endif } } } if (!wasDeleted && declarativeData) QAbstractDeclarativeData::parentChanged(declarativeData, q, o); } /*! \fn void QObject::installEventFilter(QObject *filterObj) Installs an event filter \a filterObj on this object. For example: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 14 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 \a 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 \c KeyPressEater class that eats the key presses of its monitored objects: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 15 And here's how to install it on two widgets: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 16 The QShortcut class, for example, uses this technique to intercept shortcut 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. Note that the filtering object must be in the same thread as this object. If \a filterObj is in a different thread, this function does nothing. If either \a filterObj or this object are moved to a different thread after calling this function, the event filter will not be called until both objects have the same thread affinity again (it is \e not removed). \sa removeEventFilter(), eventFilter(), event() */ void QObject::installEventFilter(QObject *obj) { Q_D(QObject); if (!obj) return; if (d->threadData != obj->d_func()->threadData) { qWarning("QObject::installEventFilter(): Cannot filter events for objects in a different thread."); return; } // clean up unused items in the list d->eventFilters.removeAll((QObject*)0); d->eventFilters.removeAll(obj); d->eventFilters.prepend(obj); } /*! Removes an event filter object \a 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). \sa installEventFilter(), eventFilter(), event() */ void QObject::removeEventFilter(QObject *obj) { Q_D(QObject); for (int i = 0; i < d->eventFilters.count(); ++i) { if (d->eventFilters.at(i) == obj) d->eventFilters[i] = 0; } } /*! \fn QObject::destroyed(QObject *obj) This signal is emitted immediately before the object \a obj is destroyed, and can not be blocked. All the objects's children are destroyed immediately after this signal is emitted. \sa deleteLater(), QPointer */ /*! Schedules this object for deletion. The object will be deleted when control returns to the event loop. If the event loop is not running when this function is called (e.g. deleteLater() is called on an object before QCoreApplication::exec()), the object will be deleted once the event loop is started. Note that entering and leaving a new event loop (e.g., by opening a modal dialog) will \e not perform the deferred deletion; for the object to be deleted, the control must return to the event loop from which deleteLater() was called. \bold{Note:} It is safe to call this function more than once; when the first deferred deletion event is delivered, any pending events for the object are removed from the event queue. \sa destroyed(), QPointer */ void QObject::deleteLater() { QCoreApplication::postEvent(this, new QEvent(QEvent::DeferredDelete)); } /*! \fn QString QObject::tr(const char *sourceText, const char *disambiguation, int n) \reentrant Returns a translated version of \a sourceText, optionally based on a \a disambiguation string and value of \a n for strings containing plurals; otherwise returns \a sourceText itself if no appropriate translated string is available. Example: \snippet mainwindows/sdi/mainwindow.cpp implicit tr context \dots If the same \a sourceText is used in different roles within the same context, an additional identifying string may be passed in \a disambiguation (0 by default). In Qt 4.4 and earlier, this was the preferred way to pass comments to translators. Example: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 17 \dots See \l{Writing Source Code for Translation} for a detailed description of Qt's translation mechanisms in general, and the \l{Writing Source Code for Translation#Disambiguation}{Disambiguation} section for information on disambiguation. \warning This method is reentrant only if all translators are installed \e 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. \sa trUtf8(), QApplication::translate(), QTextCodec::setCodecForTr(), {Internationalization with Qt} */ /*! \fn QString QObject::trUtf8(const char *sourceText, const char *disambiguation, int n) \reentrant Returns a translated version of \a sourceText, or QString::fromUtf8(\a sourceText) if there is no appropriate version. It is otherwise identical to tr(\a sourceText, \a disambiguation, \a n). Note that using the Utf8 variants of the translation functions is not required if \c CODECFORTR is already set to UTF-8 in the qmake project file and QTextCodec::setCodecForTr("UTF-8") is used. \warning This method is reentrant only if all translators are installed \e 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. \warning For portability reasons, we recommend that you use escape sequences for specifying non-ASCII characters in string literals to trUtf8(). For example: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 20 \sa tr(), QApplication::translate(), {Internationalization with Qt} */ /***************************************************************************** Signals and slots *****************************************************************************/ const int flagged_locations_count = 2; static const char* flagged_locations[flagged_locations_count] = {0}; const char *qFlagLocation(const char *method) { static int idx = 0; flagged_locations[idx] = method; idx = (idx+1) % flagged_locations_count; return method; } static int extract_code(const char *member) { // extract code, ensure QMETHOD_CODE <= code <= QSIGNAL_CODE return (((int)(*member) - '0') & 0x3); } static const char * extract_location(const char *member) { for (int i = 0; i < flagged_locations_count; ++i) { if (member == flagged_locations[i]) { // signature includes location information after the first null-terminator const char *location = member + qstrlen(member) + 1; if (*location != '\0') return location; return 0; } } return 0; } static bool check_signal_macro(const QObject *sender, const char *signal, const char *func, const char *op) { int sigcode = extract_code(signal); if (sigcode != QSIGNAL_CODE) { if (sigcode == QSLOT_CODE) qWarning("Object::%s: Attempt to %s non-signal %s::%s", func, op, sender->metaObject()->className(), signal+1); else qWarning("Object::%s: Use the SIGNAL macro to %s %s::%s", func, op, sender->metaObject()->className(), signal); return false; } return true; } static bool check_method_code(int code, const QObject *object, const char *method, const char *func) { if (code != QSLOT_CODE && code != QSIGNAL_CODE) { qWarning("Object::%s: Use the SLOT or SIGNAL macro to " "%s %s::%s", func, func, object->metaObject()->className(), method); return false; } return true; } static void err_method_notfound(const QObject *object, const char *method, const char *func) { const char *type = "method"; switch (extract_code(method)) { case QSLOT_CODE: type = "slot"; break; case QSIGNAL_CODE: type = "signal"; break; } const char *loc = extract_location(method); if (strchr(method,')') == 0) // common typing mistake qWarning("Object::%s: Parentheses expected, %s %s::%s%s%s", func, type, object->metaObject()->className(), method+1, loc ? " in ": "", loc ? loc : ""); else qWarning("Object::%s: No such %s %s::%s%s%s", func, type, object->metaObject()->className(), method+1, loc ? " in ": "", loc ? loc : ""); } static void err_info_about_objects(const char * func, const QObject * sender, const QObject * receiver) { QString a = sender ? sender->objectName() : QString(); QString b = receiver ? receiver->objectName() : QString(); if (!a.isEmpty()) qWarning("Object::%s: (sender name: '%s')", func, a.toLocal8Bit().data()); if (!b.isEmpty()) qWarning("Object::%s: (receiver name: '%s')", func, b.toLocal8Bit().data()); } /*! 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 from this object's thread context. 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. \warning As mentioned above, the return value of this function is not valid when the slot is called via a Qt::DirectConnection from a thread different from this object's thread. Do not use this function in this type of scenario. \sa senderSignalIndex(), QSignalMapper */ QObject *QObject::sender() const { Q_D(const QObject); QMutexLocker locker(signalSlotLock(this)); if (!d->currentSender) return 0; for (QObjectPrivate::Connection *c = d->senders; c; c = c->next) { if (c->sender == d->currentSender->sender) return d->currentSender->sender; } return 0; } /*! \since 4.8 Returns the meta-method index of the signal that called the currently executing slot, which is a member of the class returned by sender(). If called outside of a slot activated by a signal, -1 is returned. For signals with default parameters, this function will always return the index with all parameters, regardless of which was used with connect(). For example, the signal \c {destroyed(QObject *obj = 0)} will have two different indexes (with and without the parameter), but this function will always return the index with a parameter. This does not apply when overloading signals with different parameters. \warning This function violates the object-oriented principle of modularity. However, getting access to the signal index might be useful when many signals are connected to a single slot. \warning The return value of this function is not valid when the slot is called via a Qt::DirectConnection from a thread different from this object's thread. Do not use this function in this type of scenario. \sa sender(), QMetaObject::indexOfSignal(), QMetaObject::method() */ int QObject::senderSignalIndex() const { Q_D(const QObject); QMutexLocker locker(signalSlotLock(this)); if (!d->currentSender) return -1; for (QObjectPrivate::Connection *c = d->senders; c; c = c->next) { if (c->sender == d->currentSender->sender) return d->currentSender->signal; } return -1; } /*! Returns the number of receivers connected to the \a signal. Since both slots and signals can be used as receivers for signals, and the same connections can be made many times, the number of receivers is the same as the number of connections made from this signal. When calling this function, you can use the \c SIGNAL() macro to pass a specific signal: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 21 As the code snippet above illustrates, you can use this function to avoid emitting a signal that nobody listens to. \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. */ int QObject::receivers(const char *signal) const { Q_D(const QObject); int receivers = 0; if (signal) { QByteArray signal_name = QMetaObject::normalizedSignature(signal); signal = signal_name; #ifndef QT_NO_DEBUG if (!check_signal_macro(this, signal, "receivers", "bind")) return 0; #endif signal++; // skip code int signal_index = d->signalIndex(signal); if (signal_index < 0) { #ifndef QT_NO_DEBUG err_method_notfound(this, signal-1, "receivers"); #endif return false; } Q_D(const QObject); QMutexLocker locker(signalSlotLock(this)); if (d->connectionLists) { if (signal_index < d->connectionLists->count()) { const QObjectPrivate::Connection *c = d->connectionLists->at(signal_index).first; while (c) { receivers += c->receiver ? 1 : 0; c = c->nextConnectionList; } } } } return receivers; } /*! \internal This helper function calculates signal and method index for the given member in the specified class. \li If member.mobj is 0 then both signalIndex and methodIndex are set to -1. \li If specified member is not a member of obj instance class (or one of its parent classes) then both signalIndex and methodIndex are set to -1. This function is used by QObject::connect and QObject::disconnect which are working with QMetaMethod. \param[out] signalIndex is set to the signal index of member. If the member specified is not signal this variable is set to -1. \param[out] methodIndex is set to the method index of the member. If the member is not a method of the object specified by obj param this variable is set to -1. */ void QMetaObjectPrivate::memberIndexes(const QObject *obj, const QMetaMethod &member, int *signalIndex, int *methodIndex) { *signalIndex = -1; *methodIndex = -1; if (!obj || !member.mobj) return; const QMetaObject *m = obj->metaObject(); // Check that member is member of obj class while (m != 0 && m != member.mobj) m = m->d.superdata; if (!m) return; *signalIndex = *methodIndex = (member.handle - get(member.mobj)->methodData)/5; int signalOffset; int methodOffset; computeOffsets(m, &signalOffset, &methodOffset); *methodIndex += methodOffset; if (member.methodType() == QMetaMethod::Signal) { *signalIndex = originalClone(m, *signalIndex); *signalIndex += signalOffset; } else { *signalIndex = -1; } } static inline void check_and_warn_compat(const QMetaObject *sender, const QMetaMethod &signal, const QMetaObject *receiver, const QMetaMethod &method) { if (signal.attributes() & QMetaMethod::Compatibility) { if (!(method.attributes() & QMetaMethod::Compatibility)) qWarning("QObject::connect: Connecting from COMPAT signal (%s::%s)", sender->className(), signal.signature()); } else if ((method.attributes() & QMetaMethod::Compatibility) && method.methodType() == QMetaMethod::Signal) { qWarning("QObject::connect: Connecting from %s::%s to COMPAT slot (%s::%s)", sender->className(), signal.signature(), receiver->className(), method.signature()); } } /*! \threadsafe Creates a connection of the given \a type from the \a signal in the \a sender object to the \a method in the \a receiver object. Returns true if the connection succeeds; otherwise returns false. You must use the \c SIGNAL() and \c SLOT() macros when specifying the \a signal and the \a method, for example: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 22 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: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 23 A signal can also be connected to another signal: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 24 In this example, the \c MyWidget constructor relays a signal from a private member variable, and makes it available under a name that relates to \c 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 the same order as the order the connection was made, 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 \a signal or \a method, or if their signatures aren't compatible. By default, a signal is emitted for every connection you make; two signals are emitted for duplicate connections. You can break all of these connections with a single disconnect() call. If you pass the Qt::UniqueConnection \a type, the connection will only be made if it is not a duplicate. If there is already a duplicate (exact same signal to the exact same slot on the same objects), the connection will fail and connect will return false. The optional \a type parameter describes the type of connection to establish. In particular, it determines whether a particular signal is delivered to a slot immediately or queued for delivery at a later time. If the signal is queued, the parameters must be of types that are known to Qt's meta-object system, because Qt needs to copy the arguments to store them in an event behind the scenes. If you try to use a queued connection and get the error message \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 25 call qRegisterMetaType() to register the data type before you establish the connection. \sa disconnect(), sender(), qRegisterMetaType() */ bool QObject::connect(const QObject *sender, const char *signal, const QObject *receiver, const char *method, Qt::ConnectionType type) { { const void *cbdata[] = { sender, signal, receiver, method, &type }; if (QInternal::activateCallbacks(QInternal::ConnectCallback, (void **) cbdata)) return true; } #ifndef QT_NO_DEBUG bool warnCompat = true; #endif if (type == Qt::AutoCompatConnection) { type = Qt::AutoConnection; #ifndef QT_NO_DEBUG warnCompat = false; #endif } if (sender == 0 || receiver == 0 || signal == 0 || method == 0) { qWarning("QObject::connect: Cannot connect %s::%s to %s::%s", sender ? sender->metaObject()->className() : "(null)", (signal && *signal) ? signal+1 : "(null)", receiver ? receiver->metaObject()->className() : "(null)", (method && *method) ? method+1 : "(null)"); return false; } QByteArray tmp_signal_name; if (!check_signal_macro(sender, signal, "connect", "bind")) return false; const QMetaObject *smeta = sender->metaObject(); const char *signal_arg = signal; ++signal; //skip code int signal_index = QMetaObjectPrivate::indexOfSignalRelative(&smeta, signal, false); if (signal_index < 0) { // check for normalized signatures tmp_signal_name = QMetaObject::normalizedSignature(signal - 1); signal = tmp_signal_name.constData() + 1; smeta = sender->metaObject(); signal_index = QMetaObjectPrivate::indexOfSignalRelative(&smeta, signal, false); } if (signal_index < 0) { // re-use tmp_signal_name and signal from above smeta = sender->metaObject(); signal_index = QMetaObjectPrivate::indexOfSignalRelative(&smeta, signal, true); } if (signal_index < 0) { err_method_notfound(sender, signal_arg, "connect"); err_info_about_objects("connect", sender, receiver); return false; } signal_index = QMetaObjectPrivate::originalClone(smeta, signal_index); int signalOffset, methodOffset; computeOffsets(smeta, &signalOffset, &methodOffset); int signal_absolute_index = signal_index + methodOffset; signal_index += signalOffset; QByteArray tmp_method_name; int membcode = extract_code(method); if (!check_method_code(membcode, receiver, method, "connect")) return false; const char *method_arg = method; ++method; // skip code const QMetaObject *rmeta = receiver->metaObject(); int method_index = -1; switch (membcode) { case QSLOT_CODE: method_index = QMetaObjectPrivate::indexOfSlot(rmeta, method, false); break; case QSIGNAL_CODE: method_index = QMetaObjectPrivate::indexOfSignalRelative(&rmeta, method, false); if (method_index >= 0) method_index += rmeta->methodOffset(); break; } if (method_index < 0) { // check for normalized methods tmp_method_name = QMetaObject::normalizedSignature(method); method = tmp_method_name.constData(); // rmeta may have been modified above rmeta = receiver->metaObject(); switch (membcode) { case QSLOT_CODE: method_index = rmeta->indexOfSlot(method); break; case QSIGNAL_CODE: method_index = rmeta->indexOfSignal(method); break; } } if (method_index < 0) { err_method_notfound(receiver, method_arg, "connect"); err_info_about_objects("connect", sender, receiver); return false; } if (!QMetaObject::checkConnectArgs(signal, method)) { qWarning("QObject::connect: Incompatible sender/receiver arguments" "\n %s::%s --> %s::%s", sender->metaObject()->className(), signal, receiver->metaObject()->className(), method); return false; } int *types = 0; if ((type == Qt::QueuedConnection) && !(types = queuedConnectionTypes(smeta->method(signal_absolute_index).parameterTypes()))) return false; #ifndef QT_NO_DEBUG { QMetaMethod smethod = smeta->method(signal_absolute_index); QMetaMethod rmethod = rmeta->method(method_index); if (warnCompat) check_and_warn_compat(smeta, smethod, rmeta, rmethod); } #endif if (!QMetaObjectPrivate::connect(sender, signal_index, receiver, method_index, type, types)) return false; const_cast(sender)->connectNotify(signal - 1); return true; } /*! \since 4.8 Creates a connection of the given \a type from the \a signal in the \a sender object to the \a method in the \a receiver object. Returns true if the connection succeeds; otherwise returns false. This function works in the same way as connect(const QObject *sender, const char *signal, const QObject *receiver, const char *method, Qt::ConnectionType type) but it uses QMetaMethod to specify signal and method. \see connect(const QObject *sender, const char *signal, const QObject *receiver, const char *method, Qt::ConnectionType type) */ bool QObject::connect(const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &method, Qt::ConnectionType type) { #ifndef QT_NO_DEBUG bool warnCompat = true; #endif if (type == Qt::AutoCompatConnection) { type = Qt::AutoConnection; #ifndef QT_NO_DEBUG warnCompat = false; #endif } if (sender == 0 || receiver == 0 || signal.methodType() != QMetaMethod::Signal || method.methodType() == QMetaMethod::Constructor) { qWarning("QObject::connect: Cannot connect %s::%s to %s::%s", sender ? sender->metaObject()->className() : "(null)", signal.signature(), receiver ? receiver->metaObject()->className() : "(null)", method.signature() ); return false; } // Reconstructing SIGNAL() macro result for signal.signature() string QByteArray signalSignature; signalSignature.reserve(qstrlen(signal.signature())+1); signalSignature.append((char)(QSIGNAL_CODE + '0')); signalSignature.append(signal.signature()); { QByteArray methodSignature; methodSignature.reserve(qstrlen(method.signature())+1); methodSignature.append((char)(method.methodType() == QMetaMethod::Slot ? QSLOT_CODE : method.methodType() == QMetaMethod::Signal ? QSIGNAL_CODE : 0 + '0')); methodSignature.append(method.signature()); const void *cbdata[] = { sender, signalSignature.constData(), receiver, methodSignature.constData(), &type }; if (QInternal::activateCallbacks(QInternal::ConnectCallback, (void **) cbdata)) return true; } int signal_index; int method_index; { int dummy; QMetaObjectPrivate::memberIndexes(sender, signal, &signal_index, &dummy); QMetaObjectPrivate::memberIndexes(receiver, method, &dummy, &method_index); } const QMetaObject *smeta = sender->metaObject(); const QMetaObject *rmeta = receiver->metaObject(); if (signal_index == -1) { qWarning("QObject::connect: Can't find signal %s on instance of class %s", signal.signature(), smeta->className()); return false; } if (method_index == -1) { qWarning("QObject::connect: Can't find method %s on instance of class %s", method.signature(), rmeta->className()); return false; } if (!QMetaObject::checkConnectArgs(signal.signature(), method.signature())) { qWarning("QObject::connect: Incompatible sender/receiver arguments" "\n %s::%s --> %s::%s", smeta->className(), signal.signature(), rmeta->className(), method.signature()); return false; } int *types = 0; if ((type == Qt::QueuedConnection) && !(types = queuedConnectionTypes(signal.parameterTypes()))) return false; #ifndef QT_NO_DEBUG if (warnCompat) check_and_warn_compat(smeta, signal, rmeta, method); #endif if (!QMetaObjectPrivate::connect(sender, signal_index, receiver, method_index, type, types)) return false; const_cast(sender)->connectNotify(signalSignature.constData()); return true; } /*! \fn bool QObject::connect(const QObject *sender, const char *signal, const char *method, Qt::ConnectionType type) const \overload connect() \threadsafe Connects \a signal from the \a sender object to this object's \a method. Equivalent to connect(\a sender, \a signal, \c this, \a method, \a type). Every connection you make emits a signal, so duplicate connections emit two signals. You can break a connection using disconnect(). \sa disconnect() */ /*! \threadsafe Disconnects \a signal in object \a sender from \a method in object \a receiver. Returns true if the connection is successfully broken; otherwise returns false. 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. \list 1 \i Disconnect everything connected to an object's signals: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 26 equivalent to the non-static overloaded function \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 27 \i Disconnect everything connected to a specific signal: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 28 equivalent to the non-static overloaded function \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 29 \i Disconnect a specific receiver: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 30 equivalent to the non-static overloaded function \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 31 \endlist 0 may be used as a wildcard, meaning "any signal", "any receiving object", or "any slot in the receiving object", respectively. The \a sender may never be 0. (You cannot disconnect signals from more than one object in a single call.) If \a signal is 0, it disconnects \a receiver and \a method from any signal. If not, only the specified signal is disconnected. If \a receiver is 0, it disconnects anything connected to \a signal. If not, slots in objects other than \a receiver are not disconnected. If \a method is 0, it disconnects anything that is connected to \a receiver. If not, only slots named \a method will be disconnected, and all other slots are left alone. The \a method must be 0 if \a receiver is left out, so you cannot disconnect a specifically-named slot on all objects. \sa connect() */ bool QObject::disconnect(const QObject *sender, const char *signal, const QObject *receiver, const char *method) { if (sender == 0 || (receiver == 0 && method != 0)) { qWarning("Object::disconnect: Unexpected null parameter"); return false; } { const void *cbdata[] = { sender, signal, receiver, method }; if (QInternal::activateCallbacks(QInternal::DisconnectCallback, (void **) cbdata)) return true; } const char *signal_arg = signal; QByteArray signal_name; bool signal_found = false; if (signal) { QT_TRY { signal_name = QMetaObject::normalizedSignature(signal); signal = signal_name.constData(); } QT_CATCH (const std::bad_alloc &) { // if the signal is already normalized, we can continue. if (sender->metaObject()->indexOfSignal(signal + 1) == -1) QT_RETHROW; } if (!check_signal_macro(sender, signal, "disconnect", "unbind")) return false; signal++; // skip code } QByteArray method_name; const char *method_arg = method; int membcode = -1; bool method_found = false; if (method) { QT_TRY { method_name = QMetaObject::normalizedSignature(method); method = method_name.constData(); } QT_CATCH(const std::bad_alloc &) { // if the method is already normalized, we can continue. if (receiver->metaObject()->indexOfMethod(method + 1) == -1) QT_RETHROW; } membcode = extract_code(method); if (!check_method_code(membcode, receiver, method, "disconnect")) return false; method++; // skip code } /* We now iterate through all the sender's and receiver's meta * objects in order to also disconnect possibly shadowed signals * and slots with the same signature. */ bool res = false; const QMetaObject *smeta = sender->metaObject(); do { int signal_index = -1; if (signal) { signal_index = QMetaObjectPrivate::indexOfSignalRelative(&smeta, signal, false); if (signal_index < 0) signal_index = QMetaObjectPrivate::indexOfSignalRelative(&smeta, signal, true); if (signal_index < 0) break; signal_index = QMetaObjectPrivate::originalClone(smeta, signal_index); int signalOffset, methodOffset; computeOffsets(smeta, &signalOffset, &methodOffset); signal_index += signalOffset; signal_found = true; } if (!method) { res |= QMetaObjectPrivate::disconnect(sender, signal_index, receiver, -1); } else { const QMetaObject *rmeta = receiver->metaObject(); do { int method_index = rmeta->indexOfMethod(method); if (method_index >= 0) while (method_index < rmeta->methodOffset()) rmeta = rmeta->superClass(); if (method_index < 0) break; res |= QMetaObjectPrivate::disconnect(sender, signal_index, receiver, method_index); method_found = true; } while ((rmeta = rmeta->superClass())); } } while (signal && (smeta = smeta->superClass())); if (signal && !signal_found) { err_method_notfound(sender, signal_arg, "disconnect"); err_info_about_objects("disconnect", sender, receiver); } else if (method && !method_found) { err_method_notfound(receiver, method_arg, "disconnect"); err_info_about_objects("disconnect", sender, receiver); } if (res) const_cast(sender)->disconnectNotify(signal ? (signal - 1) : 0); return res; } /*! \since 4.8 Disconnects \a signal in object \a sender from \a method in object \a receiver. Returns true if the connection is successfully broken; otherwise returns false. This function provides the same posibilities like disconnect(const QObject *sender, const char *signal, const QObject *receiver, const char *method) but uses QMetaMethod to represent the signal and the method to be disconnected. Additionally this function returnsfalse and no signals and slots disconnected if: \list 1 \i \a signal is not a member of sender class or one of its parent classes. \i \a method is not a member of receiver class or one of its parent classes. \i \a signal instance represents not a signal. \endlist QMetaMethod() may be used as wildcard in the meaning "any signal" or "any slot in receiving object". In the same way 0 can be used for \a receiver in the meaning "any receiving object". In this case method shoud also be QMetaMethod(). \a sender parameter should be never 0. \see disconnect(const QObject *sender, const char *signal, const QObject *receiver, const char *method) */ bool QObject::disconnect(const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &method) { if (sender == 0 || (receiver == 0 && method.mobj != 0)) { qWarning("Object::disconnect: Unexpected null parameter"); return false; } if (signal.mobj) { if(signal.methodType() != QMetaMethod::Signal) { qWarning("Object::%s: Attempt to %s non-signal %s::%s", "disconnect","unbind", sender->metaObject()->className(), signal.signature()); return false; } } if (method.mobj) { if(method.methodType() == QMetaMethod::Constructor) { qWarning("QObject::disconect: cannot use constructor as argument %s::%s", receiver->metaObject()->className(), method.signature()); return false; } } // Reconstructing SIGNAL() macro result for signal.signature() string QByteArray signalSignature; if (signal.mobj) { signalSignature.reserve(qstrlen(signal.signature())+1); signalSignature.append((char)(QSIGNAL_CODE + '0')); signalSignature.append(signal.signature()); } { QByteArray methodSignature; if (method.mobj) { methodSignature.reserve(qstrlen(method.signature())+1); methodSignature.append((char)(method.methodType() == QMetaMethod::Slot ? QSLOT_CODE : method.methodType() == QMetaMethod::Signal ? QSIGNAL_CODE : 0 + '0')); methodSignature.append(method.signature()); } const void *cbdata[] = { sender, signal.mobj ? signalSignature.constData() : 0, receiver, method.mobj ? methodSignature.constData() : 0 }; if (QInternal::activateCallbacks(QInternal::ConnectCallback, (void **) cbdata)) return true; } int signal_index; int method_index; { int dummy; QMetaObjectPrivate::memberIndexes(sender, signal, &signal_index, &dummy); QMetaObjectPrivate::memberIndexes(receiver, method, &dummy, &method_index); } // If we are here sender is not null. If signal is not null while signal_index // is -1 then this signal is not a member of sender. if (signal.mobj && signal_index == -1) { qWarning("QObject::disconect: signal %s not found on class %s", signal.signature(), sender->metaObject()->className()); return false; } // If this condition is true then method is not a member of receeiver. if (receiver && method.mobj && method_index == -1) { qWarning("QObject::disconect: method %s not found on class %s", method.signature(), receiver->metaObject()->className()); return false; } if (!QMetaObjectPrivate::disconnect(sender, signal_index, receiver, method_index)) return false; const_cast(sender)->disconnectNotify(method.mobj ? signalSignature.constData() : 0); return true; } /*! \threadsafe \fn bool QObject::disconnect(const char *signal, const QObject *receiver, const char *method) \overload disconnect() Disconnects \a signal from \a method of \a receiver. A signal-slot connection is removed when either of the objects involved are destroyed. */ /*! \fn bool QObject::disconnect(const QObject *receiver, const char *method) \overload disconnect() Disconnects all signals in this object from \a receiver's \a method. A signal-slot connection is removed when either of the objects involved are destroyed. */ /*! \fn void QObject::connectNotify(const char *signal) This virtual function is called when something has been connected to \a signal in this object. If you want to compare \a signal with a specific signal, use QLatin1String and the \c SIGNAL() macro as follows: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 32 If the signal contains multiple parameters or parameters that contain spaces, call QMetaObject::normalizedSignature() on the result of the \c SIGNAL() macro. \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. \sa connect(), disconnectNotify() */ void QObject::connectNotify(const char *) { } /*! \fn void QObject::disconnectNotify(const char *signal) This virtual function is called when something has been disconnected from \a signal in this object. See connectNotify() for an example of how to compare \a signal with a specific signal. \warning This function violates the object-oriented principle of modularity. However, it might be useful for optimizing access to expensive resources. \sa disconnect(), connectNotify() */ void QObject::disconnectNotify(const char *) { } /* \internal convert a signal index from the method range to the signal range */ static int methodIndexToSignalIndex(const QMetaObject *metaObject, int signal_index) { if (signal_index < 0) return signal_index; while (metaObject && metaObject->methodOffset() > signal_index) metaObject = metaObject->superClass(); if (metaObject) { int signalOffset, methodOffset; computeOffsets(metaObject, &signalOffset, &methodOffset); if (signal_index < metaObject->methodCount()) signal_index = QMetaObjectPrivate::originalClone(metaObject, signal_index - methodOffset) + signalOffset; else signal_index = signal_index - methodOffset + signalOffset; } return signal_index; } /*!\internal \a types is a 0-terminated vector of meta types for queued connections. if \a signal_index is -1, then we effectively connect *all* signals from the sender to the receiver's slot */ bool QMetaObject::connect(const QObject *sender, int signal_index, const QObject *receiver, int method_index, int type, int *types) { signal_index = methodIndexToSignalIndex(sender->metaObject(), signal_index); return QMetaObjectPrivate::connect(sender, signal_index, receiver, method_index, type, types); } /*! \internal Same as the QMetaObject::connect, but \a signal_index must be the result of QObjectPrivate::signalIndex */ bool QMetaObjectPrivate::connect(const QObject *sender, int signal_index, const QObject *receiver, int method_index, int type, int *types) { QObject *s = const_cast(sender); QObject *r = const_cast(receiver); QOrderedMutexLocker locker(signalSlotLock(sender), signalSlotLock(receiver)); if (type & Qt::UniqueConnection) { QObjectConnectionListVector *connectionLists = QObjectPrivate::get(s)->connectionLists; if (connectionLists && connectionLists->count() > signal_index) { const QObjectPrivate::Connection *c2 = (*connectionLists)[signal_index].first; while (c2) { if (c2->receiver == receiver && c2->method == method_index) return false; c2 = c2->nextConnectionList; } } type &= Qt::UniqueConnection - 1; } QObjectPrivate::Connection *c = new QObjectPrivate::Connection; c->sender = s; c->receiver = r; c->method = method_index; c->connectionType = type; c->argumentTypes = types; c->nextConnectionList = 0; QT_TRY { QObjectPrivate::get(s)->addConnection(signal_index, c); } QT_CATCH(...) { delete c; QT_RETHROW; } c->prev = &(QObjectPrivate::get(r)->senders); c->next = *c->prev; *c->prev = c; if (c->next) c->next->prev = &c->next; QObjectPrivate *const sender_d = QObjectPrivate::get(s); if (signal_index < 0) { sender_d->connectedSignals[0] = sender_d->connectedSignals[1] = ~0; } else if (signal_index < (int)sizeof(sender_d->connectedSignals) * 8) { sender_d->connectedSignals[signal_index >> 5] |= (1 << (signal_index & 0x1f)); } return true; } /*!\internal */ bool QMetaObject::disconnect(const QObject *sender, int signal_index, const QObject *receiver, int method_index) { signal_index = methodIndexToSignalIndex(sender->metaObject(), signal_index); return QMetaObjectPrivate::disconnect(sender, signal_index, receiver, method_index); } /*!\internal Disconnect a single signal connection. If QMetaObject::connect() has been called multiple times for the same sender, signal_index, receiver and method_index only one of these connections will be removed. */ bool QMetaObject::disconnectOne(const QObject *sender, int signal_index, const QObject *receiver, int method_index) { signal_index = methodIndexToSignalIndex(sender->metaObject(), signal_index); return QMetaObjectPrivate::disconnect(sender, signal_index, receiver, method_index, QMetaObjectPrivate::DisconnectOne); } /*! \internal Helper function to remove the connection from the senders list and setting the receivers to 0 */ bool QMetaObjectPrivate::disconnectHelper(QObjectPrivate::Connection *c, const QObject *receiver, int method_index, QMutex *senderMutex, DisconnectType disconnectType) { bool success = false; while (c) { if (c->receiver && (receiver == 0 || (c->receiver == receiver && (method_index < 0 || c->method == method_index)))) { bool needToUnlock = false; QMutex *receiverMutex = 0; if (!receiver) { receiverMutex = signalSlotLock(c->receiver); // need to relock this receiver and sender in the correct order needToUnlock = QOrderedMutexLocker::relock(senderMutex, receiverMutex); } if (c->receiver) { *c->prev = c->next; if (c->next) c->next->prev = c->prev; } if (needToUnlock) receiverMutex->unlockInline(); c->receiver = 0; success = true; if (disconnectType == DisconnectOne) return success; } c = c->nextConnectionList; } return success; } /*! \internal Same as the QMetaObject::disconnect, but \a signal_index must be the result of QObjectPrivate::signalIndex */ bool QMetaObjectPrivate::disconnect(const QObject *sender, int signal_index, const QObject *receiver, int method_index, DisconnectType disconnectType) { if (!sender) return false; QObject *s = const_cast(sender); QMutex *senderMutex = signalSlotLock(sender); QMutex *receiverMutex = receiver ? signalSlotLock(receiver) : 0; QOrderedMutexLocker locker(senderMutex, receiverMutex); QObjectConnectionListVector *connectionLists = QObjectPrivate::get(s)->connectionLists; if (!connectionLists) return false; // prevent incoming connections changing the connectionLists while unlocked ++connectionLists->inUse; bool success = false; if (signal_index < 0) { // remove from all connection lists for (signal_index = -1; signal_index < connectionLists->count(); ++signal_index) { QObjectPrivate::Connection *c = (*connectionLists)[signal_index].first; if (disconnectHelper(c, receiver, method_index, senderMutex, disconnectType)) { success = true; connectionLists->dirty = true; } } } else if (signal_index < connectionLists->count()) { QObjectPrivate::Connection *c = (*connectionLists)[signal_index].first; if (disconnectHelper(c, receiver, method_index, senderMutex, disconnectType)) { success = true; connectionLists->dirty = true; } } --connectionLists->inUse; Q_ASSERT(connectionLists->inUse >= 0); if (connectionLists->orphaned && !connectionLists->inUse) delete connectionLists; return success; } /*! \fn void QMetaObject::connectSlotsByName(QObject *object) Searches recursively for all child objects of the given \a object, and connects matching signals from them to slots of \a object that follow the following form: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 33 Let's assume our object has a child object of type QPushButton with the \l{QObject::objectName}{object name} \c{button1}. The slot to catch the button's \c{clicked()} signal would be: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 34 \sa QObject::setObjectName() */ void QMetaObject::connectSlotsByName(QObject *o) { if (!o) return; const QMetaObject *mo = o->metaObject(); Q_ASSERT(mo); const QObjectList list = o->findChildren(QString()); for (int i = 0; i < mo->methodCount(); ++i) { const char *slot = mo->method(i).signature(); Q_ASSERT(slot); if (slot[0] != 'o' || slot[1] != 'n' || slot[2] != '_') continue; bool foundIt = false; for(int j = 0; j < list.count(); ++j) { const QObject *co = list.at(j); QByteArray objName = co->objectName().toAscii(); int len = objName.length(); if (!len || qstrncmp(slot + 3, objName.data(), len) || slot[len+3] != '_') continue; int sigIndex = co->d_func()->signalIndex(slot + len + 4); if (sigIndex < 0) { // search for compatible signals const QMetaObject *smo = co->metaObject(); int slotlen = qstrlen(slot + len + 4) - 1; for (int k = 0; k < co->metaObject()->methodCount(); ++k) { QMetaMethod method = smo->method(k); if (method.methodType() != QMetaMethod::Signal) continue; if (!qstrncmp(method.signature(), slot + len + 4, slotlen)) { int signalOffset, methodOffset; computeOffsets(method.enclosingMetaObject(), &signalOffset, &methodOffset); sigIndex = k + - methodOffset + signalOffset; break; } } } if (sigIndex < 0) continue; if (QMetaObjectPrivate::connect(co, sigIndex, o, i)) { foundIt = true; break; } } if (foundIt) { // we found our slot, now skip all overloads while (mo->method(i + 1).attributes() & QMetaMethod::Cloned) ++i; } else if (!(mo->method(i).attributes() & QMetaMethod::Cloned)) { qWarning("QMetaObject::connectSlotsByName: No matching signal for %s", slot); } } } static void queued_activate(QObject *sender, int signal, QObjectPrivate::Connection *c, void **argv) { if (!c->argumentTypes && c->argumentTypes != &DIRECT_CONNECTION_ONLY) { QMetaMethod m = sender->metaObject()->method(signal); int *tmp = queuedConnectionTypes(m.parameterTypes()); if (!tmp) // cannot queue arguments tmp = &DIRECT_CONNECTION_ONLY; if (!c->argumentTypes.testAndSetOrdered(0, tmp)) { if (tmp != &DIRECT_CONNECTION_ONLY) delete [] tmp; } } if (c->argumentTypes == &DIRECT_CONNECTION_ONLY) // cannot activate return; int nargs = 1; // include return type while (c->argumentTypes[nargs-1]) ++nargs; int *types = (int *) qMalloc(nargs*sizeof(int)); Q_CHECK_PTR(types); void **args = (void **) qMalloc(nargs*sizeof(void *)); Q_CHECK_PTR(args); types[0] = 0; // return type args[0] = 0; // return value for (int n = 1; n < nargs; ++n) args[n] = QMetaType::construct((types[n] = c->argumentTypes[n-1]), argv[n]); QCoreApplication::postEvent(c->receiver, new QMetaCallEvent(c->method, sender, signal, nargs, types, args)); } /*!\internal \obsolete. Used to be called from QMetaObject::activate(QObject *, QMetaObject *, int, int, void **) before Qt 4.6 */ void QMetaObject::activate(QObject *sender, int from_signal_index, int to_signal_index, void **argv) { Q_UNUSED(to_signal_index); activate(sender, from_signal_index, argv); } /*!\internal */ void QMetaObject::activate(QObject *sender, const QMetaObject *m, int local_signal_index, void **argv) { int signalOffset; int methodOffset; computeOffsets(m, &signalOffset, &methodOffset); int signal_index = signalOffset + local_signal_index; if (!sender->d_func()->isSignalConnected(signal_index)) return; // nothing connected to these signals, and no spy if (sender->d_func()->blockSig) return; int signal_absolute_index = methodOffset + local_signal_index; void *empty_argv[] = { 0 }; if (qt_signal_spy_callback_set.signal_begin_callback != 0) { qt_signal_spy_callback_set.signal_begin_callback(sender, signal_absolute_index, argv ? argv : empty_argv); } QThreadData *currentThreadData = QThreadData::current(); QMutexLocker locker(signalSlotLock(sender)); QObjectConnectionListVector *connectionLists = sender->d_func()->connectionLists; if (!connectionLists) { locker.unlock(); if (qt_signal_spy_callback_set.signal_end_callback != 0) qt_signal_spy_callback_set.signal_end_callback(sender, signal_absolute_index); return; } ++connectionLists->inUse; if (signal_index >= connectionLists->count()) { signal_index = -2; //for "all signals"; } do { QObjectPrivate::Connection *c = connectionLists->at(signal_index).first; if (!c) continue; // We need to check against last here to ensure that signals added // during the signal emission are not emitted in this emission. QObjectPrivate::Connection *last = connectionLists->at(signal_index).last; do { if (!c->receiver) continue; QObject * const receiver = c->receiver; const int method = c->method; const bool receiverInSameThread = currentThreadData == receiver->d_func()->threadData; // determine if this connection should be sent immediately or // put into the event queue if ((c->connectionType == Qt::AutoConnection && !receiverInSameThread) || (c->connectionType == Qt::QueuedConnection)) { queued_activate(sender, signal_absolute_index, c, argv ? argv : empty_argv); continue; #ifndef QT_NO_THREAD } else if (c->connectionType == Qt::BlockingQueuedConnection) { locker.unlock(); if (receiverInSameThread) { qWarning("Qt: Dead lock detected while activating a BlockingQueuedConnection: " "Sender is %s(%p), receiver is %s(%p)", sender->metaObject()->className(), sender, receiver->metaObject()->className(), receiver); } QSemaphore semaphore; QCoreApplication::postEvent(receiver, new QMetaCallEvent(method, sender, signal_absolute_index, 0, 0, argv ? argv : empty_argv, &semaphore)); semaphore.acquire(); locker.relock(); continue; #endif } QObjectPrivate::Sender currentSender; QObjectPrivate::Sender *previousSender = 0; if (receiverInSameThread) { currentSender.sender = sender; currentSender.signal = signal_absolute_index; currentSender.ref = 1; previousSender = QObjectPrivate::setCurrentSender(receiver, ¤tSender); } locker.unlock(); if (qt_signal_spy_callback_set.slot_begin_callback != 0) { qt_signal_spy_callback_set.slot_begin_callback(receiver, method, argv ? argv : empty_argv); } #if defined(QT_NO_EXCEPTIONS) metacall(receiver, QMetaObject::InvokeMetaMethod, method, argv ? argv : empty_argv); #else QT_TRY { metacall(receiver, QMetaObject::InvokeMetaMethod, method, argv ? argv : empty_argv); } QT_CATCH(...) { locker.relock(); if (receiverInSameThread) QObjectPrivate::resetCurrentSender(receiver, ¤tSender, previousSender); --connectionLists->inUse; Q_ASSERT(connectionLists->inUse >= 0); if (connectionLists->orphaned && !connectionLists->inUse) delete connectionLists; QT_RETHROW; } #endif if (qt_signal_spy_callback_set.slot_end_callback != 0) qt_signal_spy_callback_set.slot_end_callback(receiver, method); locker.relock(); if (receiverInSameThread) QObjectPrivate::resetCurrentSender(receiver, ¤tSender, previousSender); if (connectionLists->orphaned) break; } while (c != last && (c = c->nextConnectionList) != 0); if (connectionLists->orphaned) break; } while (signal_index >= 0 && (signal_index = -1)); //start over for -1 (all signal) --connectionLists->inUse; Q_ASSERT(connectionLists->inUse >= 0); if (connectionLists->orphaned) { if (!connectionLists->inUse) delete connectionLists; } else if (connectionLists->dirty) { sender->d_func()->cleanConnectionLists(); } locker.unlock(); if (qt_signal_spy_callback_set.signal_end_callback != 0) qt_signal_spy_callback_set.signal_end_callback(sender, signal_absolute_index); } /*!\internal Obsolete. (signal_index comes from indexOfMethod()) */ void QMetaObject::activate(QObject *sender, int signal_index, void **argv) { const QMetaObject *mo = sender->metaObject(); while (mo->methodOffset() > signal_index) mo = mo->superClass(); activate(sender, mo, signal_index - mo->methodOffset(), argv); } /*!\internal Obsolete, called by moc generated code before Qt 4.6 for cloned signals But since Qt 4.6, all clones are connected to their original */ void QMetaObject::activate(QObject *sender, const QMetaObject *m, int from_local_signal_index, int to_local_signal_index, void **argv) { Q_UNUSED(to_local_signal_index); Q_ASSERT(from_local_signal_index == QMetaObjectPrivate::originalClone(m, to_local_signal_index)); activate(sender, m, from_local_signal_index, argv); } /*! \internal Returns the signal index used in the internal connectionLists vector. It is different from QMetaObject::indexOfSignal(): indexOfSignal is the same as indexOfMethod while QObjectPrivate::signalIndex is smaller because it doesn't give index to slots. */ int QObjectPrivate::signalIndex(const char *signalName) const { Q_Q(const QObject); const QMetaObject *base = q->metaObject(); int relative_index = QMetaObjectPrivate::indexOfSignalRelative(&base, signalName, false); if (relative_index < 0) relative_index = QMetaObjectPrivate::indexOfSignalRelative(&base, signalName, true); if (relative_index < 0) return relative_index; relative_index = QMetaObjectPrivate::originalClone(base, relative_index); int signalOffset, methodOffset; computeOffsets(base, &signalOffset, &methodOffset); return relative_index + signalOffset; } /***************************************************************************** Properties *****************************************************************************/ #ifndef QT_NO_PROPERTIES /*! Sets the value of the object's \a name property to \a value. If the property is defined in the class using Q_PROPERTY then true is returned on success and false otherwise. If the property is not defined using Q_PROPERTY, and therefore not listed in the meta-object, it is added as a dynamic property and false is returned. Information about all available properties is provided through the metaObject() and dynamicPropertyNames(). Dynamic properties can be queried again using property() and can be removed by setting the property value to an invalid QVariant. Changing the value of a dynamic property causes a QDynamicPropertyChangeEvent to be sent to the object. \bold{Note:} Dynamic properties starting with "_q_" are reserved for internal purposes. \sa property(), metaObject(), dynamicPropertyNames() */ bool QObject::setProperty(const char *name, const QVariant &value) { Q_D(QObject); const QMetaObject* meta = metaObject(); if (!name || !meta) return false; int id = meta->indexOfProperty(name); if (id < 0) { if (!d->extraData) d->extraData = new QObjectPrivate::ExtraData; const int idx = d->extraData->propertyNames.indexOf(name); if (!value.isValid()) { if (idx == -1) return false; d->extraData->propertyNames.removeAt(idx); d->extraData->propertyValues.removeAt(idx); } else { if (idx == -1) { d->extraData->propertyNames.append(name); d->extraData->propertyValues.append(value); } else { d->extraData->propertyValues[idx] = value; } } QDynamicPropertyChangeEvent ev(name); QCoreApplication::sendEvent(this, &ev); return false; } QMetaProperty p = meta->property(id); #ifndef QT_NO_DEBUG if (!p.isWritable()) qWarning("%s::setProperty: Property \"%s\" invalid," " read-only or does not exist", metaObject()->className(), name); #endif return p.write(this, value); } /*! Returns the value of the object's \a name property. If no such property exists, the returned variant is invalid. Information about all available properties is provided through the metaObject() and dynamicPropertyNames(). \sa setProperty(), QVariant::isValid(), metaObject(), dynamicPropertyNames() */ QVariant QObject::property(const char *name) const { Q_D(const QObject); const QMetaObject* meta = metaObject(); if (!name || !meta) return QVariant(); int id = meta->indexOfProperty(name); if (id < 0) { if (!d->extraData) return QVariant(); const int i = d->extraData->propertyNames.indexOf(name); return d->extraData->propertyValues.value(i); } QMetaProperty p = meta->property(id); #ifndef QT_NO_DEBUG if (!p.isReadable()) qWarning("%s::property: Property \"%s\" invalid or does not exist", metaObject()->className(), name); #endif return p.read(this); } /*! \since 4.2 Returns the names of all properties that were dynamically added to the object using setProperty(). */ QList QObject::dynamicPropertyNames() const { Q_D(const QObject); if (d->extraData) return d->extraData->propertyNames; return QList(); } #endif // QT_NO_PROPERTIES /***************************************************************************** QObject debugging output routines. *****************************************************************************/ static void dumpRecursive(int level, QObject *object) { #if defined(QT_DEBUG) if (object) { QByteArray buf; buf.fill(' ', level / 2 * 8); if (level % 2) buf += " "; QString name = object->objectName(); QString flags = QLatin1String(""); #if 0 if (qApp->focusWidget() == object) flags += 'F'; if (object->isWidgetType()) { QWidget * w = (QWidget *)object; if (w->isVisible()) { QString t("<%1,%2,%3,%4>"); flags += t.arg(w->x()).arg(w->y()).arg(w->width()).arg(w->height()); } else { flags += 'I'; } } #endif qDebug("%s%s::%s %s", (const char*)buf, object->metaObject()->className(), name.toLocal8Bit().data(), flags.toLatin1().data()); QObjectList children = object->children(); if (!children.isEmpty()) { for (int i = 0; i < children.size(); ++i) dumpRecursive(level+1, children.at(i)); } } #else Q_UNUSED(level) Q_UNUSED(object) #endif } /*! 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). \sa dumpObjectInfo() */ void QObject::dumpObjectTree() { dumpRecursive(0, this); } /*! 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). \sa dumpObjectTree() */ void QObject::dumpObjectInfo() { #if defined(QT_DEBUG) qDebug("OBJECT %s::%s", metaObject()->className(), objectName().isEmpty() ? "unnamed" : objectName().toLocal8Bit().data()); Q_D(QObject); QMutexLocker locker(signalSlotLock(this)); // first, look for connections where this object is the sender qDebug(" SIGNALS OUT"); if (d->connectionLists) { int offset = 0; int offsetToNextMetaObject = 0; for (int signal_index = 0; signal_index < d->connectionLists->count(); ++signal_index) { if (signal_index >= offsetToNextMetaObject) { const QMetaObject *mo = metaObject(); int signalOffset, methodOffset; computeOffsets(mo, &signalOffset, &methodOffset); while (signalOffset > signal_index) { mo = mo->superClass(); offsetToNextMetaObject = signalOffset; computeOffsets(mo, &signalOffset, &methodOffset); } offset = methodOffset - signalOffset; } const QMetaMethod signal = metaObject()->method(signal_index + offset); qDebug(" signal: %s", signal.signature()); // receivers const QObjectPrivate::Connection *c = d->connectionLists->at(signal_index).first; while (c) { if (!c->receiver) { qDebug(" "); c = c->nextConnectionList; continue; } const QMetaObject *receiverMetaObject = c->receiver->metaObject(); const QMetaMethod method = receiverMetaObject->method(c->method); qDebug(" --> %s::%s %s", receiverMetaObject->className(), c->receiver->objectName().isEmpty() ? "unnamed" : qPrintable(c->receiver->objectName()), method.signature()); c = c->nextConnectionList; } } } else { qDebug( " " ); } // now look for connections where this object is the receiver qDebug(" SIGNALS IN"); if (d->senders) { for (QObjectPrivate::Connection *s = d->senders; s; s = s->next) { const QMetaMethod slot = metaObject()->method(s->method); qDebug(" <-- %s::%s %s", s->sender->metaObject()->className(), s->sender->objectName().isEmpty() ? "unnamed" : qPrintable(s->sender->objectName()), slot.signature()); } } else { qDebug(" "); } #endif } #ifndef QT_NO_USERDATA /*!\internal */ uint QObject::registerUserData() { static int user_data_registration = 0; return user_data_registration++; } /*!\internal */ QObjectUserData::~QObjectUserData() { } /*!\internal */ void QObject::setUserData(uint id, QObjectUserData* data) { Q_D(QObject); if (!d->extraData) d->extraData = new QObjectPrivate::ExtraData; if (d->extraData->userData.size() <= (int) id) d->extraData->userData.resize((int) id + 1); d->extraData->userData[id] = data; } /*!\internal */ QObjectUserData* QObject::userData(uint id) const { Q_D(const QObject); if (!d->extraData) return 0; if ((int)id < d->extraData->userData.size()) return d->extraData->userData.at(id); return 0; } #endif // QT_NO_USERDATA #ifndef QT_NO_DEBUG_STREAM QDebug operator<<(QDebug dbg, const QObject *o) { #ifndef Q_BROKEN_DEBUG_STREAM if (!o) return dbg << "QObject(0x0) "; dbg.nospace() << o->metaObject()->className() << '(' << (void *)o; if (!o->objectName().isEmpty()) dbg << ", name = " << o->objectName(); dbg << ')'; return dbg.space(); #else qWarning("This compiler doesn't support streaming QObject to QDebug"); return dbg; Q_UNUSED(o); #endif } #endif /*! \fn void QObject::insertChild(QObject *object) Use setParent() instead, i.e., call object->setParent(this). */ /*! \fn void QObject::removeChild(QObject *object) Use setParent() instead, i.e., call object->setParent(0). */ /*! \fn bool QObject::isA(const char *className) const Compare \a className with the object's metaObject()->className() instead. */ /*! \fn const char *QObject::className() const Use metaObject()->className() instead. */ /*! \fn const char *QObject::name() const Use objectName() instead. */ /*! \fn const char *QObject::name(const char *defaultName) const Use objectName() instead. */ /*! \fn void QObject::setName(const char *name) Use setObjectName() instead. */ /*! \fn bool QObject::checkConnectArgs(const char *signal, const QObject *object, const char *method) Use QMetaObject::checkConnectArgs() instead. */ /*! \fn QByteArray QObject::normalizeSignalSlot(const char *signalSlot) Use QMetaObject::normalizedSignature() instead. */ /*! \fn const char *QMetaObject::superClassName() const \internal */ /*! \macro Q_CLASSINFO(Name, Value) \relates QObject This macro associates extra information to the class, which is available using QObject::metaObject(). Except for the ActiveQt extension, Qt doesn't use this information. The extra information takes the form of a \a Name string and a \a Value literal string. Example: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 35 \sa QMetaObject::classInfo() */ /*! \macro Q_INTERFACES(...) \relates QObject This macro tells Qt which interfaces the class implements. This is used when implementing plugins. Example: \snippet examples/tools/plugandpaintplugins/basictools/basictoolsplugin.h 1 \dots \snippet examples/tools/plugandpaintplugins/basictools/basictoolsplugin.h 3 See the \l{tools/plugandpaintplugins/basictools}{Plug & Paint Basic Tools} example for details. \sa Q_DECLARE_INTERFACE(), Q_EXPORT_PLUGIN2(), {How to Create Qt Plugins} */ /*! \macro Q_PROPERTY(...) \relates QObject This macro is used for declaring properties in classes that inherit QObject. Properties behave like class data members, but they have additional features accessible through the \l {Meta-Object System}. \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 36 The property name and type and the \c READ function are required. The type can be any type supported by QVariant, or it can be a user-defined type. The other items are optional, but a \c WRITE function is common. The attributes default to true except \c USER, which defaults to false. For example: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 37 For more details about how to use this macro, and a more detailed example of its use, see the discussion on \l {Qt's Property System}. \sa {Qt's Property System} */ /*! \macro Q_ENUMS(...) \relates QObject This macro registers one or several enum types to the meta-object system. For example: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 38 If you want to register an enum that is declared in another class, the enum must be fully qualified with the name of the class defining it. In addition, the class \e defining the enum has to inherit QObject as well as declare the enum using Q_ENUMS(). \sa {Qt's Property System} */ /*! \macro Q_FLAGS(...) \relates QObject This macro registers one or several \l{QFlags}{flags types} to the meta-object system. It is typically used in a class definition to declare that values of a given enum can be used as flags and combined using the bitwise OR operator. For example, in QLibrary, the \l{QLibrary::LoadHints}{LoadHints} flag is declared in the following way: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 39a The declaration of the flags themselves is performed in the public section of the QLibrary class itself, using the \l Q_DECLARE_FLAGS() macro: \snippet doc/src/snippets/code/src_corelib_kernel_qobject.cpp 39b \note This macro takes care of registering individual flag values with the meta-object system, so it is unnecessary to use Q_ENUMS() in addition to this macro. \sa {Qt's Property System} */ /*! \macro Q_OBJECT \relates QObject The Q_OBJECT macro must appear in the private section of a class definition that declares its own signals and slots or that uses other services provided by Qt's meta-object system. For example: \snippet doc/src/snippets/signalsandslots/signalsandslots.h 1 \codeline \snippet doc/src/snippets/signalsandslots/signalsandslots.h 2 \snippet doc/src/snippets/signalsandslots/signalsandslots.h 3 \note This macro requires the class to be a subclass of QObject. Use Q_GADGET instead of Q_OBJECT to enable the meta object system's support for enums in a class that is not a QObject subclass. Q_GADGET makes a class member, \c{staticMetaObject}, available. \c{staticMetaObject} is of type QMetaObject and provides access to the enums declared with Q_ENUMS. Q_GADGET is provided only for C++. \sa {Meta-Object System}, {Signals and Slots}, {Qt's Property System} */ /*! \macro Q_SIGNALS \relates QObject Use this macro to replace the \c signals keyword in class declarations, when you want to use Qt Signals and Slots with a \l{3rd Party Signals and Slots} {3rd party signal/slot mechanism}. The macro is normally used when \c no_keywords is specified with the \c CONFIG variable in the \c .pro file, but it can be used even when \c no_keywords is \e not specified. */ /*! \macro Q_SIGNAL \relates QObject This is an additional macro that allows you to mark a single function as a signal. It can be quite useful, especially when you use a 3rd-party source code parser which doesn't understand a \c signals or \c Q_SIGNALS groups. Use this macro to replace the \c signals keyword in class declarations, when you want to use Qt Signals and Slots with a \l{3rd Party Signals and Slots} {3rd party signal/slot mechanism}. The macro is normally used when \c no_keywords is specified with the \c CONFIG variable in the \c .pro file, but it can be used even when \c no_keywords is \e not specified. */ /*! \macro Q_SLOTS \relates QObject Use this macro to replace the \c slots keyword in class declarations, when you want to use Qt Signals and Slots with a \l{3rd Party Signals and Slots} {3rd party signal/slot mechanism}. The macro is normally used when \c no_keywords is specified with the \c CONFIG variable in the \c .pro file, but it can be used even when \c no_keywords is \e not specified. */ /*! \macro Q_SLOT \relates QObject This is an additional macro that allows you to mark a single function as a slot. It can be quite useful, especially when you use a 3rd-party source code parser which doesn't understand a \c slots or \c Q_SLOTS groups. Use this macro to replace the \c slots keyword in class declarations, when you want to use Qt Signals and Slots with a \l{3rd Party Signals and Slots} {3rd party signal/slot mechanism}. The macro is normally used when \c no_keywords is specified with the \c CONFIG variable in the \c .pro file, but it can be used even when \c no_keywords is \e not specified. */ /*! \macro Q_EMIT \relates QObject Use this macro to replace the \c emit keyword for emitting signals, when you want to use Qt Signals and Slots with a \l{3rd Party Signals and Slots} {3rd party signal/slot mechanism}. The macro is normally used when \c no_keywords is specified with the \c CONFIG variable in the \c .pro file, but it can be used even when \c no_keywords is \e not specified. */ /*! \macro Q_INVOKABLE \relates QObject Apply this macro to definitions of member functions to allow them to be invoked via the meta-object system. The macro is written before the return type, as shown in the following example: \snippet snippets/qmetaobject-invokable/window.h Window class with invokable method The \c invokableMethod() function is marked up using Q_INVOKABLE, causing it to be registered with the meta-object system and enabling it to be invoked using QMetaObject::invokeMethod(). Since \c normalMethod() function is not registered in this way, it cannot be invoked using QMetaObject::invokeMethod(). */ /*! \typedef QObjectList \relates QObject Synonym for QList. */ void qDeleteInEventHandler(QObject *o) { #ifdef QT_JAMBI_BUILD if (!o) return; QObjectPrivate::get(o)->inEventHandler = false; #endif delete o; } QT_END_NAMESPACE #include "moc_qobject.cpp"