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#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