/**************************************************************************** ** ** Implementation of base class for all pointer based collection classes ** ** Created : 920820 ** ** Copyright (C) 1992-2008 Trolltech ASA. All rights reserved. ** ** This file is part of the tools module of the Qt GUI Toolkit. ** ** This file may be used under the terms of the GNU General ** Public License versions 2.0 or 3.0 as published by the Free ** Software Foundation and appearing in the files LICENSE.GPL2 ** and LICENSE.GPL3 included in the packaging of this file. ** Alternatively you may (at your option) use any later version ** of the GNU General Public License if such license has been ** publicly approved by Trolltech ASA (or its successors, if any) ** and the KDE Free Qt Foundation. ** ** Please review the following information to ensure GNU General ** Public Licensing requirements will be met: ** http://trolltech.com/products/qt/licenses/licensing/opensource/. ** If you are unsure which license is appropriate for your use, please ** review the following information: ** http://trolltech.com/products/qt/licenses/licensing/licensingoverview ** or contact the sales department at sales@trolltech.com. ** ** This file may be used under the terms of the Q Public License as ** defined by Trolltech ASA and appearing in the file LICENSE.QPL ** included in the packaging of this file. Licensees holding valid Qt ** Commercial licenses may use this file in accordance with the Qt ** Commercial License Agreement provided with the Software. ** ** This file is provided "AS IS" with NO WARRANTY OF ANY KIND, ** INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR ** A PARTICULAR PURPOSE. Trolltech reserves all rights not granted ** herein. ** **********************************************************************/ #include "qptrcollection.h" /*! \class QPtrCollection qptrcollection.h \reentrant \brief The QPtrCollection class is the base class of most pointer-based Qt collections. \ingroup collection \ingroup tools The QPtrCollection class is an abstract base class for the Qt \link collection.html collection classes\endlink QDict, QPtrList, etc. Qt also includes value based collections, e.g. QValueList, QMap, etc. A QPtrCollection 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. */ /*! \enum QPtrCollection::Item This type is the generic "item" in a QPtrCollection. */ /*! \fn QPtrCollection::QPtrCollection() Constructs a collection. The constructor is protected because QPtrCollection is an abstract class. */ /*! \fn QPtrCollection::QPtrCollection( const QPtrCollection & source ) Constructs a copy of \a source with autoDelete() set to FALSE. The constructor is protected because QPtrCollection 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 QPtrCollection::~QPtrCollection() Destroys the collection. The destructor is protected because QPtrCollection is an abstract class. */ /*! \fn bool QPtrCollection::autoDelete() const Returns the setting of the auto-delete option. The default is FALSE. \sa setAutoDelete() */ /*! \fn void QPtrCollection::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 QPtrCollection::count() const Returns the number of objects in the collection. */ /*! \fn virtual void QPtrCollection::clear() Removes all objects from the collection. The objects will be deleted if auto-delete has been enabled. \sa setAutoDelete() */ /*! \fn void QPtrCollection::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() */ QPtrCollection::Item QPtrCollection::newItem( Item d ) { return d; // just return reference }