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QPtrCollection(3qt)							      QPtrCollection(3qt)

       QPtrCollection - The base class of most pointer-based Qt collections

       All the functions in this class are reentrant when Qt is built with thread support.</p>

       #include <qptrcollection.h>

       Inherited by QAsciiDict, QCache, QDict, QIntDict, QPtrList, QPtrDict, and QPtrVector.

   Public Members
       bool autoDelete () const
       void setAutoDelete ( bool enable )
       virtual uint count () const = 0
       virtual void clear () = 0
       typedef void * Item

   Protected Members
       QPtrCollection ()
       QPtrCollection ( const QPtrCollection & source )
       virtual ~QPtrCollection ()
       virtual Item newItem ( Item d )
       virtual void deleteItem ( Item d ) = 0

       The QPtrCollection class is the base class of most pointer-based Qt collections.

       The QPtrCollection class is an abstract base class for the Qt collection classes 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 Item (generic collection item) type, which is a
       void*. The template classes that create the real collections cast the Item to the required

       See also Collection Classes and Non-GUI Classes.

   Member Type Documentation
       This type is the generic "item" in a QPtrCollection.

QPtrCollection::QPtrCollection () [protected]
       Constructs a collection. The constructor is protected because QPtrCollection is an
       abstract class.

QPtrCollection::QPtrCollection ( const QPtrCollection & source ) [protected]
       Constructs a copy of source with autoDelete() set to FALSE. The constructor is protected
       because QPtrCollection is an abstract class.

       Note that if source has autoDelete turned on, copying it will risk memory leaks, reading
       freed memory, or both.

QPtrCollection::~QPtrCollection () [virtual protected]
       Destroys the collection. The destructor is protected because QPtrCollection is an abstract

bool QPtrCollection::autoDelete () const
       Returns the setting of the auto-delete option. The default is FALSE.

       See also setAutoDelete().

void QPtrCollection::clear () [pure virtual]
       Removes all objects from the collection. The objects will be deleted if auto-delete has
       been enabled.

       See also setAutoDelete().

       Reimplemented in QAsciiDict, QCache, QDict, QIntDict, QPtrList, QPtrDict, and QPtrVector.

uint QPtrCollection::count () const [pure virtual]
       Returns the number of objects in the collection.

       Reimplemented in QAsciiDict, QCache, QDict, QIntDict, QPtrList, QPtrDict, and QPtrVector.

void QPtrCollection::deleteItem ( Item d ) [pure virtual protected]
       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 only
       delete item 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.

       See also newItem() and setAutoDelete().

Item QPtrCollection::newItem ( Item d ) [virtual protected]
       Virtual function that creates a copy of an object that is about to be inserted into the

       The default implementation returns the 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.

       See also deleteItem().

void QPtrCollection::setAutoDelete ( bool enable )
       Sets the collection to auto-delete its contents if enable is TRUE and to never delete them
       if 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.

       See also autoDelete().


       http://doc.trolltech.com/qptrcollection.html http://www.trolltech.com/faq/tech.html

       Copyright 1992-2001 Trolltech AS, http://www.trolltech.com.  See the license file included
       in the distribution for a complete license statement.

       Generated automatically from the source code.

       If you find a bug in Qt, please report it as described in
       http://doc.trolltech.com/bughowto.html.	Good bug reports help us to help you. Thank you.

       The definitive Qt documentation is provided in HTML format; it is located at
       $QTDIR/doc/html and can be read using Qt Assistant or with a web browser. This man page is
       provided as a convenience for those users who prefer man pages, although this format is
       not officially supported by Trolltech.

       If you find errors in this manual page, please report them to qt-bugs@trolltech.com.
       Please include the name of the manual page (qptrcollection.3qt) and the Qt version

Trolltech AS				 9 December 2002		      QPtrCollection(3qt)
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