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/****************************************************************************
**
** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** 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, 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.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include "qobjectcleanuphandler.h"
QT_BEGIN_NAMESPACE
/*!
\class QObjectCleanupHandler
\brief The QObjectCleanupHandler class watches the lifetime of multiple QObjects.
\ingroup objectmodel
A QObjectCleanupHandler is useful whenever you need to know when a
number of \l{QObject}s that are owned by someone else have been
deleted. This is important, for example, when referencing memory
in an application that has been allocated in a shared library.
To keep track of some \l{QObject}s, create a
QObjectCleanupHandler, and add() the objects you are interested
in. If you are no longer interested in tracking a particular
object, use remove() to remove it from the cleanup handler. If an
object being tracked by the cleanup handler gets deleted by
someone else it will automatically be removed from the cleanup
handler. You can delete all the objects in the cleanup handler
with clear(), or by destroying the cleanup handler. isEmpty()
returns true if the QObjectCleanupHandler has no objects to keep
track of.
\sa QPointer
*/
/*!
Constructs an empty QObjectCleanupHandler.
*/
QObjectCleanupHandler::QObjectCleanupHandler()
{
}
/*!
Destroys the cleanup handler. All objects in this cleanup handler
will be deleted.
\sa clear()
*/
QObjectCleanupHandler::~QObjectCleanupHandler()
{
clear();
}
/*!
Adds \a object to this cleanup handler and returns the pointer to
the object.
\sa remove()
*/
QObject *QObjectCleanupHandler::add(QObject* object)
{
if (!object)
return 0;
connect(object, SIGNAL(destroyed(QObject*)), this, SLOT(objectDestroyed(QObject*)));
cleanupObjects.insert(0, object);
return object;
}
/*!
Removes the \a object from this cleanup handler. The object will
not be destroyed.
\sa add()
*/
void QObjectCleanupHandler::remove(QObject *object)
{
int index;
if ((index = cleanupObjects.indexOf(object)) != -1) {
cleanupObjects.removeAt(index);
disconnect(object, SIGNAL(destroyed(QObject*)), this, SLOT(objectDestroyed(QObject*)));
}
}
/*!
Returns true if this cleanup handler is empty or if all objects in
this cleanup handler have been destroyed; otherwise return false.
\sa add() remove() clear()
*/
bool QObjectCleanupHandler::isEmpty() const
{
return cleanupObjects.isEmpty();
}
/*!
Deletes all objects in this cleanup handler. The cleanup handler
becomes empty.
\sa isEmpty()
*/
void QObjectCleanupHandler::clear()
{
while (!cleanupObjects.isEmpty())
delete cleanupObjects.takeFirst();
}
void QObjectCleanupHandler::objectDestroyed(QObject *object)
{
remove(object);
}
QT_END_NAMESPACE
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