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Diffstat (limited to 'src/declarative/qml/qdeclarativeincubator.cpp')
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diff --git a/src/declarative/qml/qdeclarativeincubator.cpp b/src/declarative/qml/qdeclarativeincubator.cpp deleted file mode 100644 index 6d39fc763a..0000000000 --- a/src/declarative/qml/qdeclarativeincubator.cpp +++ /dev/null @@ -1,697 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies). -** Contact: http://www.qt-project.org/ -** -** This file is part of the QtDeclarative module of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:LGPL$ -** GNU Lesser General Public License Usage -** 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. -** -** GNU General Public License Usage -** Alternatively, this file may be used under the terms of the GNU General -** Public License version 3.0 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 the GNU General -** Public License version 3.0 requirements will be met: -** http://www.gnu.org/copyleft/gpl.html. -** -** Other Usage -** Alternatively, this file may be used in accordance with the terms and -** conditions contained in a signed written agreement between you and Nokia. -** -** -** -** -** -** -** $QT_END_LICENSE$ -** -****************************************************************************/ - -#include "qdeclarativeincubator.h" -#include "qdeclarativecomponent.h" -#include "qdeclarativeincubator_p.h" - -#include "qdeclarativecompiler_p.h" -#include "qdeclarativeexpression_p.h" - -// XXX TODO -// - check that the Component.onCompleted behavior is the same as 4.8 in the synchronous and -// async if nested cases -void QDeclarativeEnginePrivate::incubate(QDeclarativeIncubator &i, QDeclarativeContextData *forContext) -{ - QDeclarativeIncubatorPrivate *p = i.d; - - QDeclarativeIncubator::IncubationMode mode = i.incubationMode(); - - if (!incubationController) - mode = QDeclarativeIncubator::Synchronous; - - if (mode == QDeclarativeIncubator::AsynchronousIfNested) { - mode = QDeclarativeIncubator::Synchronous; - - // Need to find the first constructing context and see if it is asynchronous - QDeclarativeIncubatorPrivate *parentIncubator = 0; - QDeclarativeContextData *cctxt = forContext; - while (cctxt) { - if (cctxt->activeVMEData) { - parentIncubator = (QDeclarativeIncubatorPrivate *)cctxt->activeVMEData; - break; - } - cctxt = cctxt->parent; - } - - if (parentIncubator && parentIncubator->isAsynchronous) { - mode = QDeclarativeIncubator::Asynchronous; - p->waitingOnMe = parentIncubator; - parentIncubator->waitingFor.insert(p); - } - } - - p->isAsynchronous = (mode != QDeclarativeIncubator::Synchronous); - - inProgressCreations++; - - if (mode == QDeclarativeIncubator::Synchronous) { - typedef QDeclarativeIncubatorPrivate IP; - QRecursionWatcher<IP, &IP::recursion> watcher(p); - - p->changeStatus(QDeclarativeIncubator::Loading); - - if (!watcher.hasRecursed()) { - QDeclarativeVME::Interrupt i; - p->incubate(i); - } - } else { - incubatorList.insert(p); - incubatorCount++; - - p->vmeGuard.guard(&p->vme); - p->changeStatus(QDeclarativeIncubator::Loading); - - if (incubationController) - incubationController->incubatingObjectCountChanged(incubatorCount); - } -} - -/*! -Sets the engine's incubation \a controller. The engine can only have one active controller -and it does not take ownership of it. - -\sa incubationController() -*/ -void QDeclarativeEngine::setIncubationController(QDeclarativeIncubationController *controller) -{ - Q_D(QDeclarativeEngine); - if (d->incubationController) - d->incubationController->d = 0; - d->incubationController = controller; - if (controller) controller->d = d; -} - -/*! -Returns the currently set incubation controller, or 0 if no controller has been set. - -\sa setIncubationController() -*/ -QDeclarativeIncubationController *QDeclarativeEngine::incubationController() const -{ - Q_D(const QDeclarativeEngine); - return d->incubationController; -} - -QDeclarativeIncubatorPrivate::QDeclarativeIncubatorPrivate(QDeclarativeIncubator *q, - QDeclarativeIncubator::IncubationMode m) -: q(q), status(QDeclarativeIncubator::Null), mode(m), isAsynchronous(false), progress(Execute), - result(0), component(0), vme(this), waitingOnMe(0) -{ -} - -QDeclarativeIncubatorPrivate::~QDeclarativeIncubatorPrivate() -{ -} - -void QDeclarativeIncubatorPrivate::clear() -{ - if (next.isInList()) { - next.remove(); - Q_ASSERT(component); - QDeclarativeEnginePrivate *enginePriv = QDeclarativeEnginePrivate::get(component->engine); - component->release(); - component = 0; - enginePriv->incubatorCount--; - QDeclarativeIncubationController *controller = enginePriv->incubationController; - if (controller) - controller->incubatingObjectCountChanged(enginePriv->incubatorCount); - } else if (component) { - component->release(); - component = 0; - } - if (!rootContext.isNull()) { - rootContext->activeVMEData = 0; - rootContext = 0; - } - - if (nextWaitingFor.isInList()) { - Q_ASSERT(waitingOnMe); - nextWaitingFor.remove(); - waitingOnMe = 0; - } -} - -/*! -\class QDeclarativeIncubationController -\brief QDeclarativeIncubationController instances drive the progress of QDeclarativeIncubators - -In order to behave asynchronously and not introduce stutters or freezes in an application, -the process of creating objects a QDeclarativeIncubators must be driven only during the -application's idle time. QDeclarativeIncubationController allows the application to control -exactly when, how often and for how long this processing occurs. - -A QDeclarativeIncubationController derived instance should be created and set on a -QDeclarativeEngine by calling the QDeclarativeEngine::setIncubationController() method. -Processing is then controlled by calling the QDeclarativeIncubationController::incubateFor() -or QDeclarativeIncubationController::incubateWhile() methods as dictated by the application's -requirements. - -For example, this is an example of a incubation controller that will incubate for a maximum -of 5 milliseconds out of every 16 milliseconds. - -\code -class PeriodicIncubationController : public QObject, - public QDeclarativeIncubationController -{ -public: - PeriodicIncubationController() { - startTimer(16); - } - -protected: - virtual void timerEvent(QTimerEvent *) { - incubateFor(5); - } -}; -\endcode - -Although the previous example would work, it is not optimal. Real world incubation -controllers should try and maximize the amount of idle time they consume - rather -than a static amount like 5 milliseconds - while not disturbing the application. -*/ - -/*! -Create a new incubation controller. -*/ -QDeclarativeIncubationController::QDeclarativeIncubationController() -: d(0) -{ -} - -/*! \internal */ -QDeclarativeIncubationController::~QDeclarativeIncubationController() -{ - if (d) QDeclarativeEnginePrivate::get(d)->setIncubationController(0); - d = 0; -} - -/*! -Return the QDeclarativeEngine this incubation controller is set on, or 0 if it -has not been set on any engine. -*/ -QDeclarativeEngine *QDeclarativeIncubationController::engine() const -{ - return QDeclarativeEnginePrivate::get(d); -} - -/*! -Return the number of objects currently incubating. -*/ -int QDeclarativeIncubationController::incubatingObjectCount() const -{ - if (d) - return d->incubatorCount; - else - return 0; -} - -/*! -Called when the number of incubating objects changes. \a incubatingObjectCount is the -new number of incubating objects. - -The default implementation does nothing. -*/ -void QDeclarativeIncubationController::incubatingObjectCountChanged(int incubatingObjectCount) -{ - Q_UNUSED(incubatingObjectCount); -} - -void QDeclarativeIncubatorPrivate::incubate(QDeclarativeVME::Interrupt &i) -{ - if (!component) - return; - typedef QDeclarativeIncubatorPrivate IP; - QRecursionWatcher<IP, &IP::recursion> watcher(this); - - QDeclarativeEngine *engine = component->engine; - QDeclarativeEnginePrivate *enginePriv = QDeclarativeEnginePrivate::get(engine); - - bool guardOk = vmeGuard.isOK(); - vmeGuard.clear(); - - if (!guardOk) { - QDeclarativeError error; - error.setUrl(component->url); - error.setDescription(QDeclarativeComponent::tr("Object destroyed during incubation")); - errors << error; - progress = QDeclarativeIncubatorPrivate::Completed; - - goto finishIncubate; - } - - if (progress == QDeclarativeIncubatorPrivate::Execute) { - enginePriv->referenceScarceResources(); - QObject *tresult = vme.execute(&errors, i); - enginePriv->dereferenceScarceResources(); - - if (watcher.hasRecursed()) - return; - - result = tresult; - if (errors.isEmpty() && result == 0) - goto finishIncubate; - - if (result) { - QDeclarativeData *ddata = QDeclarativeData::get(result); - Q_ASSERT(ddata); - ddata->indestructible = true; - - q->setInitialState(result); - } - - if (watcher.hasRecursed()) - return; - - if (errors.isEmpty()) - progress = QDeclarativeIncubatorPrivate::Completing; - else - progress = QDeclarativeIncubatorPrivate::Completed; - - changeStatus(calculateStatus()); - - if (watcher.hasRecursed()) - return; - - if (i.shouldInterrupt()) - goto finishIncubate; - } - - if (progress == QDeclarativeIncubatorPrivate::Completing) { - do { - if (watcher.hasRecursed()) - return; - - QDeclarativeContextData *ctxt = vme.complete(i); - if (ctxt) { - rootContext = ctxt; - progress = QDeclarativeIncubatorPrivate::Completed; - goto finishIncubate; - } - } while (!i.shouldInterrupt()); - } - -finishIncubate: - if (progress == QDeclarativeIncubatorPrivate::Completed && waitingFor.isEmpty()) { - typedef QDeclarativeIncubatorPrivate IP; - - QDeclarativeIncubatorPrivate *isWaiting = waitingOnMe; - clear(); - - if (isWaiting) { - QRecursionWatcher<IP, &IP::recursion> watcher(isWaiting); - changeStatus(calculateStatus()); - if (!watcher.hasRecursed()) - isWaiting->incubate(i); - } else { - changeStatus(calculateStatus()); - } - - enginePriv->inProgressCreations--; - - if (0 == enginePriv->inProgressCreations) { - while (enginePriv->erroredBindings) { - enginePriv->warning(enginePriv->erroredBindings->error); - enginePriv->erroredBindings->removeError(); - } - } - } else { - vmeGuard.guard(&vme); - } -} - -/*! -Incubate objects for \a msecs, or until there are no more objects to incubate. -*/ -void QDeclarativeIncubationController::incubateFor(int msecs) -{ - if (!d || d->incubatorCount == 0) - return; - - QDeclarativeVME::Interrupt i(msecs * 1000000); - i.reset(); - do { - QDeclarativeIncubatorPrivate *p = (QDeclarativeIncubatorPrivate*)d->incubatorList.first(); - p->incubate(i); - } while (d && d->incubatorCount != 0 && !i.shouldInterrupt()); -} - -/*! -Incubate objects while the bool pointed to by \a flag is true, or until there are no -more objects to incubate, or up to msecs if msecs is not zero. - -Generally this method is used in conjunction with a thread or a UNIX signal that sets -the bool pointed to by \a flag to false when it wants incubation to be interrupted. -*/ -void QDeclarativeIncubationController::incubateWhile(volatile bool *flag, int msecs) -{ - if (!d || d->incubatorCount == 0) - return; - - QDeclarativeVME::Interrupt i(flag, msecs * 1000000); - i.reset(); - do { - QDeclarativeIncubatorPrivate *p = (QDeclarativeIncubatorPrivate*)d->incubatorList.first(); - p->incubate(i); - } while (d && d->incubatorCount != 0 && !i.shouldInterrupt()); -} - -/*! -\class QDeclarativeIncubator -\brief The QDeclarativeIncubator class allows QML objects to be created asynchronously. - -Creating QML objects - like delegates in a view, or a new page in an application - can take -a noticable amount of time, especially on resource constrained mobile devices. When an -application uses QDeclarativeComponent::create() directly, the QML object instance is created -synchronously which, depending on the complexity of the object, can cause noticable pauses or -stutters in the application. - -The use of QDeclarativeIncubator gives more control over the creation of a QML object, -including allowing it to be created asynchronously using application idle time. The following -example shows a simple use of QDeclarativeIncubator. - -\code -QDeclarativeIncubator incubator; -component->create(incubator); - -while (incubator.isReady()) { - QCoreApplication::processEvents(QEventLoop::AllEvents, 50); -} - -QObject *object = incubator.object(); -\endcode - -Asynchronous incubators are controlled by a QDeclarativeIncubationController that is -set on the QDeclarativeEngine, which lets the engine know when the application is idle and -incubating objects should be processed. If an incubation controller is not set on the -QDeclarativeEngine, QDeclarativeIncubator creates objects synchronously regardless of the -specified IncubationMode. - -QDeclarativeIncubator supports three incubation modes: -\list -\i Synchronous The creation occurs synchronously. That is, once the -QDeclarativeComponent::create() call returns, the incubator will already be in either the -Error or Ready state. A synchronous incubator has no real advantage compared to using -the synchronous creation methods on QDeclarativeComponent directly, but it may simplify an -application's implementation to use the same API for both synchronous and asynchronous -creations. - -\i Asynchronous (default) The creation occurs asynchronously, assuming a -QDeclarativeIncubatorController is set on the QDeclarativeEngine. - -The incubator will remain in the Loading state until either the creation is complete or an error -occurs. The statusChanged() callback can be used to be notified of status changes. - -Applications should use the Asynchronous incubation mode to create objects that are not needed -immediately. For example, the ListView element uses Asynchronous incubation to create objects -that are slightly off screen while the list is being scrolled. If, during asynchronous creation, -the object is needed immediately the QDeclarativeIncubator::forceCompletion() method can be called -to complete the creation process synchronously. - -\i AsynchronousIfNested The creation will occur asynchronously if part of a nested asynchronous -creation, or synchronously if not. - -In most scenarios where a QML element or component wants the appearance of a synchronous -instantiation, it should use this mode. - -This mode is best explained with an example. When the ListView element is first created, it needs -to populate itself with an initial set of delegates to show. If the ListView was 400 pixels high, -and each delegate was 100 pixels high, it would need to create four initial delegate instances. If -the ListView used the Asynchronous incubation mode, the ListView would always be created empty and -then, sometime later, the four initial elements would appear. - -Conversely, if the ListView was to use the Synchronous incubation mode it would behave correctly -but it may introduce stutters into the application. As QML would have to stop and instantiate the -ListView's delegates synchronously, if the ListView was part of a QML component that was being -instantiated asynchronously this would undo much of the benefit of asynchronous instantiation. - -The AsynchronousIfNested mode reconciles this problem. By using AsynchronousIfNested, the ListView -delegates are instantiated asynchronously if the ListView itself is already part of an asynchronous -instantiation, and synchronously otherwise. In the case of a nested asynchronous instantiation, the -outer asynchronous instantiation will not complete until after all the nested instantiations have also -completed. This ensures that by the time the outer asynchronous instantitation completes, inner -elements like ListView have already completed loading their initial delegates. - -It is almost always incorrect to use the Synchronous incubation mode - elements or components that -want the appearance of synchronous instantiation, but without the downsides of introducing freezes -or stutters into the application, should use the AsynchronousIfNested incubation mode. -\endlist -*/ - -/*! -Create a new incubator with the specified \a mode -*/ -QDeclarativeIncubator::QDeclarativeIncubator(IncubationMode mode) -: d(new QDeclarativeIncubatorPrivate(this, mode)) -{ -} - -/*! \internal */ -QDeclarativeIncubator::~QDeclarativeIncubator() -{ - clear(); - - delete d; d = 0; -} - -/*! -\enum QDeclarativeIncubator::IncubationMode - -Specifies the mode the incubator operates in. Regardless of the incubation mode, a -QDeclarativeIncubator will behave synchronously if the QDeclarativeEngine does not have -a QDeclarativeIncubationController set. - -\value Asynchronous The object will be created asynchronously. -\value AsynchronousIfNested If the object is being created in a context that is already part -of an asynchronous creation, this incubator will join that existing incubation and execute -asynchronously. The existing incubation will not become Ready until both it and this -incubation have completed. Otherwise, the incubation will execute synchronously. -\value Synchronous The object will be created synchronously. -*/ - -/*! -\enum QDeclarativeIncubator::Status - -Specifies the status of the QDeclarativeIncubator. - -\value Null Incubation is not in progress. Call QDeclarativeComponent::create() to begin incubating. -\value Ready The object is fully created and can be accessed by calling object(). -\value Loading The object is in the process of being created. -\value Error An error occurred. The errors can be access by calling errors(). -*/ - -/*! -Clears the incubator. Any in-progress incubation is aborted. If the incubator is in the -Ready state, the created object is \b not deleted. -*/ -void QDeclarativeIncubator::clear() -{ - typedef QDeclarativeIncubatorPrivate IP; - QRecursionWatcher<IP, &IP::recursion> watcher(d); - - Status s = status(); - - if (s == Null) - return; - - QDeclarativeEnginePrivate *enginePriv = 0; - if (s == Loading) { - Q_ASSERT(d->component); - enginePriv = QDeclarativeEnginePrivate::get(d->component->engine); - if (d->result) d->result->deleteLater(); - d->result = 0; - } - - d->clear(); - - d->vme.reset(); - d->vmeGuard.clear(); - - Q_ASSERT(d->component == 0); - Q_ASSERT(d->waitingOnMe == 0); - Q_ASSERT(d->waitingFor.isEmpty()); - Q_ASSERT(!d->nextWaitingFor.isInList()); - - d->errors.clear(); - d->progress = QDeclarativeIncubatorPrivate::Execute; - d->result = 0; - - if (s == Loading) { - Q_ASSERT(enginePriv); - - enginePriv->inProgressCreations--; - if (0 == enginePriv->inProgressCreations) { - while (enginePriv->erroredBindings) { - enginePriv->warning(enginePriv->erroredBindings->error); - enginePriv->erroredBindings->removeError(); - } - } - } - - d->changeStatus(Null); -} - -/*! -Force any in-progress incubation to finish synchronously. Once this call -returns, the incubator will not be in the Loading state. -*/ -void QDeclarativeIncubator::forceCompletion() -{ - QDeclarativeVME::Interrupt i; - while (Loading == status()) { - while (Loading == status() && !d->waitingFor.isEmpty()) - static_cast<QDeclarativeIncubatorPrivate *>(d->waitingFor.first())->incubate(i); - if (Loading == status()) - d->incubate(i); - } -} - -/*! -Returns true if the incubator's status() is Null. -*/ -bool QDeclarativeIncubator::isNull() const -{ - return status() == Null; -} - -/*! -Returns true if the incubator's status() is Ready. -*/ -bool QDeclarativeIncubator::isReady() const -{ - return status() == Ready; -} - -/*! -Returns true if the incubator's status() is Error. -*/ -bool QDeclarativeIncubator::isError() const -{ - return status() == Error; -} - -/*! -Returns true if the incubator's status() is Loading. -*/ -bool QDeclarativeIncubator::isLoading() const -{ - return status() == Loading; -} - -/*! -Return the list of errors encountered while incubating the object. -*/ -QList<QDeclarativeError> QDeclarativeIncubator::errors() const -{ - return d->errors; -} - -/*! -Return the incubation mode passed to the QDeclarativeIncubator constructor. -*/ -QDeclarativeIncubator::IncubationMode QDeclarativeIncubator::incubationMode() const -{ - return d->mode; -} - -/*! -Return the current status of the incubator. -*/ -QDeclarativeIncubator::Status QDeclarativeIncubator::status() const -{ - return d->status; -} - -/*! -Return the incubated object if the status is Ready, otherwise 0. -*/ -QObject *QDeclarativeIncubator::object() const -{ - if (status() != Ready) return 0; - else return d->result; -} - -/*! -Called when the status of the incubator changes. \a status is the new status. - -The default implementation does nothing. -*/ -void QDeclarativeIncubator::statusChanged(Status status) -{ - Q_UNUSED(status); -} - -/*! -Called after the object is first created, but before property bindings are -evaluated and, if applicable, QDeclarativeParserStatus::componentComplete() is -called. This is equivalent to the point between QDeclarativeComponent::beginCreate() -and QDeclarativeComponent::endCreate(), and can be used to assign initial values -to the object's properties. - -The default implementation does nothing. -*/ -void QDeclarativeIncubator::setInitialState(QObject *object) -{ - Q_UNUSED(object); -} - -void QDeclarativeIncubatorPrivate::changeStatus(QDeclarativeIncubator::Status s) -{ - if (s == status) - return; - - status = s; - q->statusChanged(status); -} - -QDeclarativeIncubator::Status QDeclarativeIncubatorPrivate::calculateStatus() const -{ - if (!errors.isEmpty()) - return QDeclarativeIncubator::Error; - else if (result && progress == QDeclarativeIncubatorPrivate::Completed && - waitingFor.isEmpty()) - return QDeclarativeIncubator::Ready; - else if (component) - return QDeclarativeIncubator::Loading; - else - return QDeclarativeIncubator::Null; -} - |