/**************************************************************************** ** ** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies). ** Contact: http://www.qt-project.org/legal ** ** 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 Digia. For licensing terms and ** conditions see http://qt.digia.com/licensing. For further information ** use the contact form at http://qt.digia.com/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 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, Digia gives you certain additional ** rights. These rights are described in the Digia 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. ** ** ** $QT_END_LICENSE$ ** ****************************************************************************/ #include "qqmlparserstatus.h" QT_BEGIN_NAMESPACE /*! \class QQmlParserStatus \since 5.0 \inmodule QtQml \brief The QQmlParserStatus class provides updates on the QML parser state. QQmlParserStatus provides a mechanism for classes instantiated by a QQmlEngine to receive notification at key points in their creation. This class is often used for optimization purposes, as it allows you to defer an expensive operation until after all the properties have been set on an object. For example, QML's \l {Text} element uses the parser status to defer text layout until all of its properties have been set (we don't want to layout when the \c text is assigned, and then relayout when the \c font is assigned, and relayout again when the \c width is assigned, and so on). Be aware that QQmlParserStatus methods are only called when a class is instantiated by a QQmlEngine. If you create the same class directly from C++, these methods will not be called automatically. To avoid this problem, it is recommended that you start deferring operations from classBegin instead of from the initial creation of your class. This will still prevent multiple revaluations during initial binding assignment in QML, but will not defer operations invoked from C++. To use QQmlParserStatus, you must inherit both a QObject-derived class and QQmlParserStatus, and use the Q_INTERFACES() macro. \code class MyObject : public QObject, public QQmlParserStatus { Q_OBJECT Q_INTERFACES(QQmlParserStatus) public: MyObject(QObject *parent = 0); ... void classBegin(); void componentComplete(); } \endcode The \l {Qt Quick 1} version of this class is named QDeclarativeParserStatus. */ /*! \internal */ QQmlParserStatus::QQmlParserStatus() : d(0) { } /*! \internal */ QQmlParserStatus::~QQmlParserStatus() { if(d) (*d) = 0; } /*! \fn void QQmlParserStatus::classBegin() Invoked after class creation, but before any properties have been set. */ /*! \fn void QQmlParserStatus::componentComplete() Invoked after the root component that caused this instantiation has completed construction. At this point all static values and binding values have been assigned to the class. */ QT_END_NAMESPACE