/**************************************************************************** ** ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). ** All rights reserved. ** Contact: Nokia Corporation (qt-info@nokia.com) ** ** This file is part of the Qt3Support 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 "q3ptrcollection.h" QT_BEGIN_NAMESPACE /*! \class Q3PtrCollection \reentrant \brief The Q3PtrCollection class is the base class of most pointer-based Qt collections. \compat The Q3PtrCollection class is an abstract base class for the Qt collection classes QDict, Q3PtrList, etc. A Q3PtrCollection only knows about the number of objects in the collection and the deletion strategy (see setAutoDelete()). A collection is implemented using the \c Item (generic collection item) type, which is a \c void*. The template classes that create the real collections cast the \c Item to the required type. */ /*! \typedef Q3PtrCollection::Item This type is the generic "item" in a Q3PtrCollection. */ /*! \fn Q3PtrCollection::Q3PtrCollection() Constructs a collection. The constructor is protected because Q3PtrCollection is an abstract class. */ /*! \fn Q3PtrCollection::Q3PtrCollection( const Q3PtrCollection & source ) Constructs a copy of \a source with autoDelete() set to false. The constructor is protected because Q3PtrCollection is an abstract class. Note that if \a source has autoDelete turned on, copying it will risk memory leaks, reading freed memory, or both. */ /*! \fn Q3PtrCollection::~Q3PtrCollection() Destroys the collection. The destructor is protected because Q3PtrCollection is an abstract class. */ /*! \fn bool Q3PtrCollection::autoDelete() const Returns the setting of the auto-delete option. The default is false. \sa setAutoDelete() */ /*! \fn void Q3PtrCollection::setAutoDelete( bool enable ) Sets the collection to auto-delete its contents if \a enable is true and to never delete them if \a enable is false. If auto-deleting is turned on, all the items in a collection are deleted when the collection itself is deleted. This is convenient if the collection has the only pointer to the items. The default setting is false, for safety. If you turn it on, be careful about copying the collection - you might find yourself with two collections deleting the same items. Note that the auto-delete setting may also affect other functions in subclasses. For example, a subclass that has a remove() function will remove the item from its data structure, and if auto-delete is enabled, will also delete the item. \sa autoDelete() */ /*! \fn virtual uint Q3PtrCollection::count() const Returns the number of objects in the collection. */ /*! \fn virtual void Q3PtrCollection::clear() Removes all objects from the collection. The objects will be deleted if auto-delete has been enabled. \sa setAutoDelete() */ /*! \fn void Q3PtrCollection::deleteItem( Item d ) Reimplement this function if you want to be able to delete items. Deletes an item that is about to be removed from the collection. This function has to reimplemented in the collection template classes, and should \e only delete item \a d if auto-delete has been enabled. \warning If you reimplement this function you must also reimplement the destructor and call the virtual function clear() from your destructor. This is due to the way virtual functions and destructors work in C++: Virtual functions in derived classes cannot be called from a destructor. If you do not do this, your deleteItem() function will not be called when the container is destroyed. \sa newItem(), setAutoDelete() */ /*! Virtual function that creates a copy of an object that is about to be inserted into the collection. The default implementation returns the \a d pointer, i.e. no copy is made. This function is seldom reimplemented in the collection template classes. It is not common practice to make a copy of something that is being inserted. \sa deleteItem() */ Q3PtrCollection::Item Q3PtrCollection::newItem(Item d) { return d; // just return reference } QT_END_NAMESPACE