QCollection - The base class of all Qt collections

       #include <qcollection.h>

       Inherited by QGCache, QGDict, QGList and QGVector.

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

   Protected Members
       QCollection ()
       QCollection ( const QCollection & )
       virtual ~QCollection ()
       virtual Item newItem ( Item )
       virtual void deleteItem ( Item )


DESCRIPTION

       The QCollection class is the base class of all Qt
       collections.

       The QCollection class is an abstract base class for the Qt
       collection classes QDict, QList etc. via QGDict, QGList
       etc.

       A QCollection knows only 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 type.

       See also Collection Classes

   Member Type Documentation

QCollection::Item

       This type is the generic "item" in a QCollection.


MEMBER FUNCTION DOCUMENTATION


QCollection::QCollection () [protected]

       Constructs a collection. The constructor is protected
       because QCollection is an abstract class.


QCollection::QCollection ( const QCollection & source )

       [protected]
       Constructs a copy of source with autoDelete() set to
       FALSE. The constructor is protected because QCollection is


       Note that if source has autoDelete turned on, copying it
       is a good way to get memory leaks, reading freed memory,
       or both.


QCollection::~QCollection () [virtual protected]

       Destroys the collection. The destructor is protected
       because QCollection is an abstract class.


bool QCollection::autoDelete () const

       Returns the setting of the auto-delete option (default is
       FALSE).

       See also setAutoDelete().


virtual void QCollection::clear () [virtual]

       Removes all objects from the collection. The objects will
       be deleted if auto-delete has been enabled.

       See also setAutoDelete().

       Reimplemented in QGCache, QIntDict, QDict, QPtrDict,
       QAsciiDict, QQueue, QGVector, QAsciiCache, QStack,
       QVector, QList, QGDict, QGList, QIntCache and QCache.


virtual uint QCollection::count () const [virtual]

       Returns the number of objects in the collection.

       Reimplemented in QGDict, QGList, QAsciiCache, QGCache,
       QVector, QPtrDict, QIntCache, QDict, QAsciiDict, QCache,
       QQueue, QGVector, QIntDict, QList and QStack.


void QCollection::deleteItem ( Item d ) [protected]

       Virtual function that deletes an item that is about to be
       removed from the collection.

       The default implementation deletes d pointer if and only
       if auto-delete has been enabled.

       This function is always reimplemented in the collection
       template classes.

       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
       destructed.

       See also newItem() and setAutoDelete().

       Virtual function that creates a copy of an object that is
       about to be inserted into the collection.

       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 QCollection::setAutoDelete ( bool enable )

       Sets the auto-delete option of the collection.

       Enabling auto-delete (enable is TRUE) will delete objects
       that are removed from the collection. This can be useful
       if the collection has the only reference to the objects.
       (Note that the object can still be copied using the copy
       constructor - copying such objects is a good way to get
       memory leaks, reading freed memory or both.)

       Disabling auto-delete (enable is FALSE) will not delete
       objects that are removed from the collection. This is
       useful if the objects are part of many collections.

       The default setting is FALSE.

       See also autoDelete().

       Examples: grapher/grapher.cpp


SEE ALSO

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


COPYRIGHT

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


AUTHOR

       Generated automatically from the source code.


BUGS

       If you find a bug in Qt, please report it as described in
       http://doc.trolltech.com/bughowto.html.  Good bug reports
       make our job much simpler. Thank you.

       In case of content or formattting problems with this
       manual page, please report them to qt-bugs@trolltech.com.
       Please include the name of the manual page
       (qcollection.3qt) and the Qt version (2.3.1).


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