diff options
Diffstat (limited to 'src/corelib/kernel/qobject.cpp')
| -rw-r--r-- | src/corelib/kernel/qobject.cpp | 94 |
1 files changed, 57 insertions, 37 deletions
diff --git a/src/corelib/kernel/qobject.cpp b/src/corelib/kernel/qobject.cpp index cc689657d22..a52fd25e088 100644 --- a/src/corelib/kernel/qobject.cpp +++ b/src/corelib/kernel/qobject.cpp @@ -522,13 +522,6 @@ void QMetaCallEvent::placeMetaCall(QObject *object) 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. @@ -549,6 +542,41 @@ void QMetaCallEvent::placeMetaCall(QObject *object) Some QObject functions, e.g. children(), return a QObjectList. QObjectList is a typedef for QList<QObject *>. + \section1 Thread Affinity + + A QObject instance is said to have a \e{thread affinity}, or that + it \e{lives} in a certain thread. When a QObject receives a + \l{Qt::QueuedConnection}{queued signal} or a \l{The Event + System#Sending Events}{posted event}, the slot or event handler + will run in the thread that the object lives in. + + \note If a QObject has no thread affinity (that is, if thread() + returns zero), or if it lives in a thread that has no running event + loop, then it cannot receive queued signals or posted events. + + By default, a QObject lives in the thread in which it is created. + An object's thread affinity can be queried using thread() and + changed using moveToThread(). + + All QObjects must live in the same thread as their parent. Consequently: + + \list + \li setParent() will fail if the two QObjects involved live in + different threads. + \li When a QObject is moved to another thread, all its children + will be automatically moved too. + \li moveToThread() will fail if the QObject has a parent. + \li If \l{QObject}s are created within QThread::run(), they cannot + become children of the QThread object because the QThread does + not live in the thread that calls QThread::run(). + \endlist + + \note A QObject's member variables \e{do not} automatically become + its children. The parent-child relationship must be set by either + passing a pointer to the child's \l{QObject()}{constructor}, or by + calling setParent(). Without this step, the object's member variables + will remain in the old thread when moveToThread() is called. + \target No copy constructor \section1 No copy constructor or assignment operator @@ -977,9 +1005,9 @@ QObjectPrivate::Connection::~Connection() /*! \fn bool QObject::inherits(const char *className) const - Returns true if this object is an instance of a class that + Returns \c 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. + className; otherwise returns \c false. A class is considered to inherit itself. @@ -1040,7 +1068,7 @@ void QObject::setObjectName(const QString &name) /*! \fn bool QObject::isWidgetType() const - Returns true if the object is a widget; otherwise returns false. + Returns \c true if the object is a widget; otherwise returns \c false. Calling this function is equivalent to calling \c{inherits("QWidget")}, except that it is much faster. @@ -1049,7 +1077,7 @@ void QObject::setObjectName(const QString &name) /*! \fn bool QObject::isWindowType() const - Returns true if the object is a window; otherwise returns false. + Returns \c true if the object is a window; otherwise returns \c false. Calling this function is equivalent to calling \c{inherits("QWindow")}, except that it is much faster. @@ -1144,7 +1172,7 @@ void QObject::timerEvent(QTimerEvent *) 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 + returns \c 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). @@ -1221,7 +1249,7 @@ bool QObject::eventFilter(QObject * /* watched */, QEvent * /* event */) /*! \fn bool QObject::signalsBlocked() const - Returns true if signals are blocked; otherwise returns false. + Returns \c true if signals are blocked; otherwise returns \c false. Signals are not blocked by default. @@ -2029,14 +2057,9 @@ void QObject::deleteLater() *****************************************************************************/ -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; + QThreadData::current()->flaggedSignatures.store(method); return method; } @@ -2048,14 +2071,11 @@ static int extract_code(const char *member) 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; - } + if (QThreadData::current()->flaggedSignatures.contains(member)) { + // signature includes location information after the first null-terminator + const char *location = member + qstrlen(member) + 1; + if (*location != '\0') + return location; } return 0; } @@ -2259,8 +2279,8 @@ int QObject::receivers(const char *signal) const /*! \since 5.0 - Returns true if the \a signal is connected to at least one receiver, - otherwise returns false. + Returns \c true if the \a signal is connected to at least one receiver, + otherwise returns \c false. \a signal must be a signal member of this object, otherwise the behaviour is undefined. @@ -2662,8 +2682,8 @@ QMetaObject::Connection QObject::connect(const QObject *sender, const QMetaMetho \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 receiver. Returns \c true if the connection is successfully broken; + otherwise returns \c false. A signal-slot connection is removed when either of the objects involved are destroyed. @@ -2828,8 +2848,8 @@ bool QObject::disconnect(const QObject *sender, const char *signal, \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. + \a receiver. Returns \c true if the connection is successfully broken; + otherwise returns \c false. This function provides the same possibilities like disconnect(const QObject *sender, const char *signal, const QObject *receiver, const char *method) @@ -2978,7 +2998,7 @@ void QObject::connectNotify(const QMetaMethod &signal) If all signals were disconnected from this object (e.g., the signal argument to disconnect() was 0), disconnectNotify() is only called once, and the \a signal will be an invalid - QMetaMethod (QMetaMethod::isValid() returns false). + QMetaMethod (QMetaMethod::isValid() returns \c false). \warning This function violates the object-oriented principle of modularity. However, it might be useful for optimizing access to @@ -4486,8 +4506,8 @@ bool QObject::disconnect(const QMetaObject::Connection &connection) \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 receiver. Returns \c true if the connection is successfully broken; + otherwise returns \c false. A signal-slot connection is removed when either of the objects involved are destroyed. @@ -4637,7 +4657,7 @@ QMetaObject::Connection::~Connection() /*! \fn QMetaObject::Connection::operator bool() const - Returns true if the connection is valid. + Returns \c true if the connection is valid. The connection is valid if the call to QObject::connect succeeded. The connection is invalid if QObject::connect was not able to find |