diff options
Diffstat (limited to 'src/qml/qml/qqmlincubator.cpp')
| -rw-r--r-- | src/qml/qml/qqmlincubator.cpp | 189 |
1 files changed, 118 insertions, 71 deletions
diff --git a/src/qml/qml/qqmlincubator.cpp b/src/qml/qml/qqmlincubator.cpp index 7d4ffcec3f..5c18230450 100644 --- a/src/qml/qml/qqmlincubator.cpp +++ b/src/qml/qml/qqmlincubator.cpp @@ -1,47 +1,10 @@ -/**************************************************************************** -** -** Copyright (C) 2016 The Qt Company Ltd. -** Contact: https://www.qt.io/licensing/ -** -** This file is part of the QtQml module of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:LGPL$ -** Commercial License Usage -** Licensees holding valid commercial Qt licenses may use this file in -** accordance with the commercial license agreement provided with the -** Software or, alternatively, in accordance with the terms contained in -** a written agreement between you and The Qt Company. For licensing terms -** and conditions see https://www.qt.io/terms-conditions. For further -** information use the contact form at https://www.qt.io/contact-us. -** -** GNU Lesser General Public License Usage -** Alternatively, this file may be used under the terms of the GNU Lesser -** General Public License version 3 as published by the Free Software -** Foundation and appearing in the file LICENSE.LGPL3 included in the -** packaging of this file. Please review the following information to -** ensure the GNU Lesser General Public License version 3 requirements -** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. -** -** GNU General Public License Usage -** Alternatively, this file may be used under the terms of the GNU -** General Public License version 2.0 or (at your option) the GNU General -** Public license version 3 or any later version approved by the KDE Free -** Qt Foundation. The licenses are as published by the Free Software -** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 -** included in the packaging of this file. Please review the following -** information to ensure the GNU General Public License requirements will -** be met: https://www.gnu.org/licenses/gpl-2.0.html and -** https://www.gnu.org/licenses/gpl-3.0.html. -** -** $QT_END_LICENSE$ -** -****************************************************************************/ +// Copyright (C) 2016 The Qt Company Ltd. +// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only #include "qqmlincubator.h" #include "qqmlcomponent.h" #include "qqmlincubator_p.h" -#include "qqmlexpression_p.h" #include "qqmlobjectcreator_p.h" #include <private/qqmlcomponent_p.h> @@ -140,7 +103,10 @@ QQmlIncubatorPrivate::~QQmlIncubatorPrivate() void QQmlIncubatorPrivate::clear() { - compilationUnit = nullptr; + // reset the tagged pointer + if (requiredPropertiesFromComponent) + requiredPropertiesFromComponent = decltype(requiredPropertiesFromComponent){}; + compilationUnit.reset(); if (next.isInList()) { next.remove(); enginePriv->incubatorCount--; @@ -152,7 +118,7 @@ void QQmlIncubatorPrivate::clear() if (!rootContext.isNull()) { if (rootContext->incubator()) rootContext->setIncubator(nullptr); - rootContext = nullptr; + rootContext.setContextData({}); } if (nextWaitingFor.isInList()) { @@ -211,9 +177,15 @@ protected: }; \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. +Although the example works, it is heavily simplified. Real world incubation controllers +try and maximize the amount of idle time they consume while not disturbing the +application. Using a static amount of 5 milliseconds like above may both leave idle +time on the table in some frames and disturb the application in others. + +\l{QQuickWindow}, \l{QQuickView}, and \l{QQuickWidget} all pre-create an incubation +controller that spaces out incubation over multiple frames using a more intelligent +algorithm. You rarely have to write your own. + */ /*! @@ -263,12 +235,13 @@ void QQmlIncubatorPrivate::forceCompletion(QQmlInstantiationInterrupt &i) { while (QQmlIncubator::Loading == status) { while (QQmlIncubator::Loading == status && !waitingFor.isEmpty()) - static_cast<QQmlIncubatorPrivate *>(waitingFor.first())->forceCompletion(i); + waitingFor.first()->forceCompletion(i); if (QQmlIncubator::Loading == status) incubate(i); } } + void QQmlIncubatorPrivate::incubate(QQmlInstantiationInterrupt &i) { if (!compilationUnit) @@ -280,6 +253,20 @@ void QQmlIncubatorPrivate::incubate(QQmlInstantiationInterrupt &i) // get a copy of the engine pointer as it might get reset; QQmlEnginePrivate *enginePriv = this->enginePriv; + // Incubating objects takes quite a bit more stack space than our usual V4 function + enum { EstimatedSizeInV4Frames = 2 }; + QV4::ExecutionEngineCallDepthRecorder<EstimatedSizeInV4Frames> callDepthRecorder( + compilationUnit->engine); + if (callDepthRecorder.hasOverflow()) { + QQmlError error; + error.setMessageType(QtCriticalMsg); + error.setUrl(compilationUnit->url()); + error.setDescription(QQmlComponent::tr("Maximum call stack size exceeded.")); + errors << error; + progress = QQmlIncubatorPrivate::Completed; + goto finishIncubate; + } + if (!vmeGuard.isOK()) { QQmlError error; error.setMessageType(QtInfoMsg); @@ -300,11 +287,12 @@ void QQmlIncubatorPrivate::incubate(QQmlInstantiationInterrupt &i) if (!tresult) errors = creator->errors; else { - RequiredProperties& requiredProperties = creator->requiredProperties(); + RequiredProperties* requiredProperties = creator->requiredProperties(); for (auto it = initialProperties.cbegin(); it != initialProperties.cend(); ++it) { auto component = tresult; auto name = it.key(); - QQmlProperty prop = QQmlComponentPrivate::removePropertyFromRequired(component, name, requiredProperties); + QQmlProperty prop = QQmlComponentPrivate::removePropertyFromRequired( + component, name, requiredProperties, QQmlEnginePrivate::get(enginePriv)); if (!prop.isValid() || !prop.write(it.value())) { QQmlError error{}; error.setUrl(compilationUnit->url()); @@ -331,9 +319,9 @@ void QQmlIncubatorPrivate::incubate(QQmlInstantiationInterrupt &i) ddata->rootObjectInCreation = false; if (q) { q->setInitialState(result); - if (creator && !creator->requiredProperties().empty()) { - const auto& unsetRequiredProperties = creator->requiredProperties(); - for (const auto& unsetRequiredProperty: unsetRequiredProperties) + if (creator && !creator->requiredProperties()->empty()) { + const RequiredProperties *unsetRequiredProperties = creator->requiredProperties(); + for (const auto& unsetRequiredProperty: *unsetRequiredProperties) errors << QQmlComponentPrivate::unsetRequiredPropertyToQQmlError(unsetRequiredProperty); } } @@ -395,6 +383,37 @@ finishIncubate: } /*! + \internal + This is used to mimic the behavior of incubate when the + Component we want to incubate refers to a creatable + QQmlType (i.e., it is the result of loadFromModule). + */ +void QQmlIncubatorPrivate::incubateCppBasedComponent(QQmlComponent *component, QQmlContext *context) +{ + auto compPriv = QQmlComponentPrivate::get(component); + Q_ASSERT(compPriv->loadedType.isCreatable()); + std::unique_ptr<QObject> object(component->beginCreate(context)); + component->setInitialProperties(object.get(), initialProperties); + if (auto props = compPriv->state.requiredProperties()) { + requiredPropertiesFromComponent = props; + requiredPropertiesFromComponent.setTag(HadTopLevelRequired::Yes); + } + q->setInitialState(object.get()); + if (requiredPropertiesFromComponent && !requiredPropertiesFromComponent->isEmpty()) { + for (const RequiredPropertyInfo &unsetRequiredProperty : + std::as_const(*requiredPropertiesFromComponent)) { + errors << QQmlComponentPrivate::unsetRequiredPropertyToQQmlError(unsetRequiredProperty); + } + } else { + compPriv->completeCreate(); + result = object.release(); + progress = QQmlIncubatorPrivate::Completed; + } + changeStatus(calculateStatus()); + +} + +/*! Incubate objects for \a msecs, or until there are no more objects to incubate. */ void QQmlIncubationController::incubateFor(int msecs) @@ -402,8 +421,8 @@ void QQmlIncubationController::incubateFor(int msecs) if (!d || !d->incubatorCount) return; - QQmlInstantiationInterrupt i(msecs * Q_INT64_C(1000000)); - i.reset(); + QDeadlineTimer deadline(msecs); + QQmlInstantiationInterrupt i(deadline); do { static_cast<QQmlIncubatorPrivate*>(d->incubatorList.first())->incubate(i); } while (d && d->incubatorCount != 0 && !i.shouldInterrupt()); @@ -426,8 +445,7 @@ void QQmlIncubationController::incubateWhile(std::atomic<bool> *flag, int msecs) if (!d || !d->incubatorCount) return; - QQmlInstantiationInterrupt i(flag, msecs * Q_INT64_C(1000000)); - i.reset(); + QQmlInstantiationInterrupt i(flag, msecs ? QDeadlineTimer(msecs) : QDeadlineTimer::Forever); do { static_cast<QQmlIncubatorPrivate*>(d->incubatorList.first())->incubate(i); } while (d && d->incubatorCount != 0 && !i.shouldInterrupt()); @@ -445,25 +463,37 @@ synchronously which, depending on the complexity of the object, can cause notic stutters in the application. The use of QQmlIncubator gives more control over the creation of a QML object, -including allowing it to be created asynchronously using application idle time. The following +including allowing it to be created asynchronously using application idle time. The following example shows a simple use of QQmlIncubator. \code +// Initialize the incubator QQmlIncubator incubator; component->create(incubator); +\endcode -while (!incubator.isReady()) { - QCoreApplication::processEvents(QEventLoop::AllEvents, 50); -} +Let the incubator run for a while (normally by returning control to the event loop), +then poll it. There are a number of ways to get back to the incubator later. You may +want to connect to one of the signals sent by \l{QQuickWindow}, or you may want to run +a \l{QTimer} especially for that. You may also need the object for some specific +purpose and poll the incubator when that purpose arises. -QObject *object = incubator.object(); +\code +// Poll the incubator +if (incubator.isReady()) { + QObject *object = incubator.object(); + // Use created object +} \endcode -Asynchronous incubators are controlled by a QQmlIncubationController that is -set on the QQmlEngine, which lets the engine know when the application is idle and +Asynchronous incubators are controlled by a \l{QQmlIncubationController} that is +set on the \l{QQmlEngine}, 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 -QQmlEngine, QQmlIncubator creates objects synchronously regardless of the -specified IncubationMode. +\l{QQmlEngine}, \l{QQmlIncubator} creates objects synchronously regardless of the +specified IncubationMode. By default, no incubation controller is set. However, +\l{QQuickView}, \l{QQuickWindow} and \l{QQuickWidget} all set incubation controllers +on their respective \l{QQmlEngine}s. These incubation controllers space out incubations +across multiple frames while the view is being rendered. QQmlIncubator supports three incubation modes: \list @@ -683,21 +713,28 @@ QObject *QQmlIncubator::object() const } /*! -Return a list of properties which are required but haven't been set yet. +Return a pointer to a list of properties which are required but haven't +been set yet. This list can be modified, so that subclasses which implement special logic setInitialProperties can mark properties set there as no longer required. \sa QQmlIncubator::setInitialProperties \since 5.15 */ -RequiredProperties &QQmlIncubatorPrivate::requiredProperties() +RequiredProperties *QQmlIncubatorPrivate::requiredProperties() { - return creator->requiredProperties(); + if (creator) + return creator->requiredProperties(); + else + return requiredPropertiesFromComponent.data(); } -bool QQmlIncubatorPrivate::hadRequiredProperties() const +bool QQmlIncubatorPrivate::hadTopLevelRequiredProperties() const { - return creator->componentHadRequiredProperties(); + if (creator) + return creator->componentHadTopLevelRequiredProperties(); + else + return requiredPropertiesFromComponent.tag() == HadTopLevelRequired::Yes; } /*! @@ -723,13 +760,23 @@ void QQmlIncubator::statusChanged(Status status) } /*! -Called after the \a object is first created, but before property bindings are -evaluated and, if applicable, QQmlParserStatus::componentComplete() is -called. This is equivalent to the point between QQmlComponent::beginCreate() +Called after the \a object is first created, but before complex property +bindings are evaluated and, if applicable, QQmlParserStatus::componentComplete() +is called. This is equivalent to the point between QQmlComponent::beginCreate() and QQmlComponent::completeCreate(), and can be used to assign initial values to the object's properties. The default implementation does nothing. + +\note Simple bindings such as numeric literals are evaluated before +setInitialState() is called. The categorization of bindings into simple and +complex ones is intentionally unspecified and may change between versions of +Qt and depending on whether and how you are using \l{qmlcachegen}. You should +not rely on any particular binding to be evaluated either before or after +setInitialState() is called. For example, a constant expression like +\e{MyType.EnumValue} may be recognized as such at compile time or deferred +to be executed as binding. The same holds for constant expressions like +\e{-(5)} or \e{"a" + " constant string"}. */ void QQmlIncubator::setInitialState(QObject *object) { |