/**************************************************************************** ** ** Copyright (C) 1992-2007 Trolltech ASA. All rights reserved. ** ** This file is part of the QtCore module of the Qt Toolkit. ** ** This file may be used under the terms of the GNU General Public ** License version 2.0 as published by the Free Software Foundation ** and appearing in the file LICENSE.GPL included in the packaging of ** this file. Please review the following information to ensure GNU ** General Public Licensing requirements will be met: ** http://trolltech.com/products/qt/licenses/licensing/opensource/ ** ** If you are unsure which license is appropriate for your use, please ** review the following information: ** http://trolltech.com/products/qt/licenses/licensing/licensingoverview ** or contact the sales department at sales@trolltech.com. ** ** In addition, as a special exception, Trolltech gives you certain ** additional rights. These rights are described in the Trolltech GPL ** Exception version 1.0, which can be found at ** http://www.trolltech.com/products/qt/gplexception/ and in the file ** GPL_EXCEPTION.txt in this package. ** ** In addition, as a special exception, Trolltech, as the sole copyright ** holder for Qt Designer, grants users of the Qt/Eclipse Integration ** plug-in the right for the Qt/Eclipse Integration to link to ** functionality provided by Qt Designer and its related libraries. ** ** Trolltech reserves all rights not expressly granted herein. ** ** Trolltech ASA (c) 2007 ** ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. ** ****************************************************************************/ #include "qabstracteventdispatcher.h" #include "qabstracteventdispatcher_p.h" #include "qthread.h" #include #include static QBasicAtomic timerId = Q_ATOMIC_INIT(1); void QAbstractEventDispatcherPrivate::init() { Q_Q(QAbstractEventDispatcher); if (threadData->eventDispatcher != 0) { qWarning("QAbstractEventDispatcher: An event dispatcher has already been created for this thread"); } else { threadData->eventDispatcher = q; } } /*! \class QAbstractEventDispatcher \brief The QAbstractEventDispatcher class manages Qt's event queue, excluding GUI-related events. \ingroup application \ingroup events An event dispatcher receives events from the window system and other sources. It then sends them to the QCoreApplication or QApplication instance for processing and delivery. QAbstractEventDispatcher provides fine-grained control over event delivery. For simple control of event processing use QCoreApplication::processEvents(). For finer control of the application's event loop, call instance() and call functions on the QAbstractEventDispatcher object that is returned. If you want to use your own instance of QAbstractEventDispatcher or of a QAbstractEventDispatcher subclass, you must create your instance \e before you create the QApplication object. The main event loop is started by calling QCoreApplication::exec(), and stopped by calling QCoreApplication::exit(). Local event loops can be created using QEventLoop. Programs that perform long operations can call processEvents() with a bitwise OR combination of various QEventLoop::ProcessEventsFlag values to control which events should be delivered. QAbstractEventDispatcher also allows the integration of an external event loop with the Qt event loop. For example, the Motif Extension included with Qt includes a reimplementation of QAbstractEventDispatcher that merges Qt and Motif events together. \sa QEventLoop, QCoreApplication */ /*! Constructs a new event dispatcher with the given \a parent. */ QAbstractEventDispatcher::QAbstractEventDispatcher(QObject *parent) : QObject(*new QAbstractEventDispatcherPrivate, parent) { Q_D(QAbstractEventDispatcher); d->init(); } /*! \internal */ QAbstractEventDispatcher::QAbstractEventDispatcher(QAbstractEventDispatcherPrivate &dd, QObject *parent) : QObject(dd, parent) { Q_D(QAbstractEventDispatcher); d->init(); } /*! Destroys the event dispatcher. */ QAbstractEventDispatcher::~QAbstractEventDispatcher() { } /*! Returns a pointer to the event dispatcher object for the specified \a thread. If \a thread is zero, the current thread is used. If no event dispatcher exists for the specified thread, this function returns 0. \bold{Note:} If Qt is built without thread support, the \a thread argument is ignored. */ QAbstractEventDispatcher *QAbstractEventDispatcher::instance(QThread *thread) { QThreadData *data = thread ? QThreadData::get2(thread) : QThreadData::current(); return data->eventDispatcher; } /*! \fn bool QAbstractEventDispatcher::processEvents(QEventLoop::ProcessEventsFlags flags) Processes pending events that match \a flags until there are no more events to process. Returns true if an event was processed; otherwise returns false. This function is especially useful if you have a long running operation and want to show its progress without allowing user input; i.e. by using the QEventLoop::ExcludeUserInputEvents flag. If the QEventLoop::WaitForMoreEvents flag is set in \a flags, the behavior of this function is as follows: \list \i If events are available, this function returns after processing them. \i If no events are available, this function will wait until more are available and return after processing newly available events. \endlist If the QEventLoop::WaitForMoreEvents flag is not set in \a flags, and no events are available, this function will return immediately. \bold{Note:} This function does not process events continuously; it returns after all available events are processed. \sa hasPendingEvents() */ /*! \fn bool QAbstractEventDispatcher::hasPendingEvents() Returns true if there is an event waiting; otherwise returns false. */ /*! \fn void QAbstractEventDispatcher::registerSocketNotifier(QSocketNotifier *notifier) Registers \a notifier with the event loop. Subclasses must implement this method to tie a socket notifier into another event loop. */ /*! \fn void QAbstractEventDispatcher::unregisterSocketNotifier(QSocketNotifier *notifier) Unregisters \a notifier from the event dispatcher. Subclasses must reimplement this method to tie a socket notifier into another event loop. Reimplementations must call the base implementation. */ /*! \fn int QAbstractEventDispatcher::registerTimer(int interval, QObject *object) Registers a timer with the specified \a interval for the given \a object. */ int QAbstractEventDispatcher::registerTimer(int interval, QObject *object) { int id = timerId.fetchAndAdd(1); registerTimer(id, interval, object); return id; } /*! \fn void QAbstractEventDispatcher::registerTimer(int timerId, int interval, QObject *object) Register a timer with the specified \a timerId and \a interval for the given \a object. */ /*! \fn bool QAbstractEventDispatcher::unregisterTimer(int timerId) Unregisters the timer with the given \a timerId. Returns true if successful; otherwise returns false. \sa registerTimer(), unregisterTimers() */ /*! \fn bool QAbstractEventDispatcher::unregisterTimers(QObject *object) Unregisters all the timers associated with the given \a object. Returns true if all timers were successful removed; otherwise returns false. \sa unregisterTimer(), registeredTimers() */ /*! \fn QList QAbstractEventDispatcher::registeredTimers(QObject *object) const Returns a list of registered timers for \a object. The timer ID is the first member in each pair; the interval is the second. */ /*! \fn void QAbstractEventDispatcher::wakeUp() \threadsafe Wakes up the event loop. \sa awake() */ /*! \fn void QAbstractEventDispatcher::interrupt() Interrupts event dispatching; i.e. the event dispatcher will return from processEvents() as soon as possible. */ /*! \fn void QAbstractEventDispatcher::flush() Flushes the event queue. This normally returns almost immediately. Does nothing on platforms other than X11. */ // ### DOC: Are these called when the _application_ starts/stops or just // when the current _event loop_ starts/stops? /*! \internal */ void QAbstractEventDispatcher::startingUp() { } /*! \internal */ void QAbstractEventDispatcher::closingDown() { } /*! \typedef QAbstractEventDispatcher::TimerInfo Typedef for QPair. The first component of the pair is the timer ID; the second component is the interval. \sa registeredTimers() */ /*! \typedef QAbstractEventDispatcher::EventFilter Typedef for a function with the signature \code bool myEventFilter(void *message); \endcode \sa setEventFilter(), filterEvent() */ /*! Sets the event filter \a filter. Returns a pointer to the filter function previously defined. The event filter is a function that receives all messages taken from the system event loop before the event is dispatched to the respective target. This includes messages that are not sent to Qt objects. The function can return true to stop the event to be processed by Qt, or false to continue with the standard event processing. Only one filter can be defined, but the filter can use the return value to call the previously set event filter. By default, no filter is set (i.e. the function returns 0). */ QAbstractEventDispatcher::EventFilter QAbstractEventDispatcher::setEventFilter(EventFilter filter) { Q_D(QAbstractEventDispatcher); EventFilter oldFilter = d->event_filter; d->event_filter = filter; return oldFilter; } /*! Sends \a message through the event filter that was set by setEventFilter(). If no event filter has been set, this function returns false; otherwise, this function returns the result of the event filter function. Subclasses of QAbstractEventDispatcher \e must call this function for \e all messages received from the system to ensure compatibility with any extensions that may be used in the application. \sa setEventFilter() */ bool QAbstractEventDispatcher::filterEvent(void *message) { Q_D(QAbstractEventDispatcher); if (d->event_filter) return d->event_filter(message); return false; } /*! \fn void QAbstractEventDispatcher::awake() This signal is emitted after the event loop returns from a function that could block. \sa wakeUp() aboutToBlock() */ /*! \fn void QAbstractEventDispatcher::aboutToBlock() This signal is emitted before the event loop calls a function that could block. \sa awake() */