1QPtrQueue(3qt)                                                  QPtrQueue(3qt)
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NAME

6       QPtrQueue - Template class that provides a queue
7

SYNOPSIS

9       #include <qptrqueue.h>
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11   Public Members
12       QPtrQueue ()
13       QPtrQueue ( const QPtrQueue<type> & queue )
14       ~QPtrQueue ()
15       QPtrQueue<type> & operator= ( const QPtrQueue<type> & queue )
16       bool autoDelete () const
17       void setAutoDelete ( bool enable )
18       uint count () const
19       bool isEmpty () const
20       void enqueue ( const type * d )
21       type * dequeue ()
22       bool remove ()
23       void clear ()
24       type * head () const
25       operator type * () const
26       type * current () const
27
28   Protected Members
29       virtual QDataStream & read ( QDataStream & s, QPtrCollection::Item &
30           item )
31       virtual QDataStream & write ( QDataStream & s, QPtrCollection::Item
32           item ) const
33

DESCRIPTION

35       The QPtrQueue class is a template class that provides a queue.
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37       QValueVector can be used as an STL-compatible alternative to this
38       class.
39
40       A template instance QPtrQueue<X> is a queue that operates on pointers
41       to X (X*).
42
43       A queue is a first in, first out structure. Items are added to the tail
44       of the queue with enqueue() and retrieved from the head with dequeue().
45       You can peek at the head item without dequeing it using head().
46
47       You can control the queue's deletion policy with setAutoDelete().
48
49       For compatibility with the QPtrCollection classes, current() and
50       remove() are provided; both operate on the head().
51
52       See also QPtrList, QPtrStack, Collection Classes, and Non-GUI Classes.
53

MEMBER FUNCTION DOCUMENTATION

QPtrQueue::QPtrQueue ()

56       Creates an empty queue with autoDelete() set to FALSE.
57

QPtrQueue::QPtrQueue ( const QPtrQueue<type> & queue )

59       Creates a queue from queue.
60
61       Only the pointers are copied; the items are not. The autoDelete() flag
62       is set to FALSE.
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QPtrQueue::~QPtrQueue ()

65       Destroys the queue. Items in the queue are deleted if autoDelete() is
66       TRUE.
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bool QPtrQueue::autoDelete () const

69       Returns the setting of the auto-delete option. The default is FALSE.
70
71       See also setAutoDelete().
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void QPtrQueue::clear ()

74       Removes all items from the queue, and deletes them if autoDelete() is
75       TRUE.
76
77       See also remove().
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uint QPtrQueue::count () const

80       Returns the number of items in the queue.
81
82       See also isEmpty().
83

type * QPtrQueue::current () const

85       Returns a pointer to the head item in the queue. The queue is not
86       changed. Returns 0 if the queue is empty.
87
88       See also dequeue() and isEmpty().
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type * QPtrQueue::dequeue ()

91       Takes the head item from the queue and returns a pointer to it. Returns
92       0 if the queue is empty.
93
94       See also enqueue() and count().
95

void QPtrQueue::enqueue ( const type * d )

97       Adds item d to the tail of the queue.
98
99       See also count() and dequeue().
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type * QPtrQueue::head () const

102       Returns a pointer to the head item in the queue. The queue is not
103       changed. Returns 0 if the queue is empty.
104
105       See also dequeue() and isEmpty().
106

bool QPtrQueue::isEmpty () const

108       Returns TRUE if the queue is empty; otherwise returns FALSE.
109
110       See also count(), dequeue(), and head().
111

QPtrQueue::operator type * () const

113       Returns a pointer to the head item in the queue. The queue is not
114       changed. Returns 0 if the queue is empty.
115
116       See also dequeue() and isEmpty().
117

QPtrQueue<type> & QPtrQueue::operator= ( const QPtrQueue<type> & queue )

119       Assigns queue to this queue and returns a reference to this queue.
120
121       This queue is first cleared and then each item in queue is enqueued to
122       this queue. Only the pointers are copied.
123
124       Warning: The autoDelete() flag is not modified. If it it TRUE for both
125       queue and this queue, deleting the two lists will cause double-deletion
126       of the items.
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QDataStream & QPtrQueue::read ( QDataStream & s, QPtrCollection::Item & item )

129       [virtual protected]
130       Reads a queue item, item, from the stream s and returns a reference to
131       the stream.
132
133       The default implementation sets item to 0.
134
135       See also write().
136

bool QPtrQueue::remove ()

138       Removes the head item from the queue, and returns TRUE if there was an
139       item, i.e. the queue wasn't empty; otherwise returns FALSE.
140
141       The item is deleted if autoDelete() is TRUE.
142
143       See also head(), isEmpty(), and dequeue().
144

void QPtrQueue::setAutoDelete ( bool enable )

146       Sets the queue to auto-delete its contents if enable is TRUE and not to
147       delete them if enable is FALSE.
148
149       If auto-deleting is turned on, all the items in a queue are deleted
150       when the queue itself is deleted. This can be quite convenient if the
151       queue has the only pointer to the items.
152
153       The default setting is FALSE, for safety. If you turn it on, be careful
154       about copying the queue: you might find yourself with two queues
155       deleting the same items.
156
157       See also autoDelete().
158

QDataStream & QPtrQueue::write ( QDataStream & s, QPtrCollection::Item item )

160       const [virtual protected]
161       Writes a queue item, item, to the stream s and returns a reference to
162       the stream.
163
164       The default implementation does nothing.
165
166       See also read().
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168

SEE ALSO

170       http://doc.trolltech.com/qptrqueue.html
171       http://www.trolltech.com/faq/tech.html
172
174       Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com.  See the
175       license file included in the distribution for a complete license
176       statement.
177

AUTHOR

179       Generated automatically from the source code.
180

BUGS

182       If you find a bug in Qt, please report it as described in
183       http://doc.trolltech.com/bughowto.html.  Good bug reports help us to
184       help you. Thank you.
185
186       The definitive Qt documentation is provided in HTML format; it is
187       located at $QTDIR/doc/html and can be read using Qt Assistant or with a
188       web browser. This man page is provided as a convenience for those users
189       who prefer man pages, although this format is not officially supported
190       by Trolltech.
191
192       If you find errors in this manual page, please report them to qt-
193       bugs@trolltech.com.  Please include the name of the manual page
194       (qptrqueue.3qt) and the Qt version (3.3.8).
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198Trolltech AS                    2 February 2007                 QPtrQueue(3qt)
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