1QIntDict(3qt) QIntDict(3qt)
2
6 QIntDict - Template class that provides a dictionary based on long keys
7
9 #include <qintdict.h>
10 Inherits QPtrCollection.
12 Public Members
14 QIntDict ( int size = 17 )
15 QIntDict ( const QIntDict<type> & dict )
16 ~QIntDict ()
17 QIntDict<type> & operator= ( const QIntDict<type> & dict )
18 virtual uint count () const
19 uint size () const
20 bool isEmpty () const
21 void insert ( long key, const type * item )
22 void replace ( long key, const type * item )
23 bool remove ( long key )
24 type * take ( long key )
25 type * find ( long key ) const
26 type * operator[] ( long key ) const
27 virtual void clear ()
28 void resize ( uint newsize )
29 void statistics () const
30 Important Inherited Members
32 bool autoDelete () const
33 void setAutoDelete ( bool enable )
34 Protected Members
36 virtual QDataStream & read ( QDataStream & s, QPtrCollection::Item &
37 item )
38 virtual QDataStream & write ( QDataStream & s, QPtrCollection::Item )
39 const
40
42 The QIntDict class is a template class that provides a dictionary based
43 on long keys.
44 QMap is an STL-compatible alternative to this class.
46 QIntDict is implemented as a template class. Define a template instance
48 QIntDict<X> to create a dictionary that operates on pointers to X (X*).
49 A dictionary is a collection of key-value pairs. The key is an long
51 used for insertion, removal and lookup. The value is a pointer.
52 Dictionaries provide very fast insertion and lookup.
53 Example:
55 QIntDict<QLineEdit> fields; // long int keys, QLineEdit* values
57 for ( int i = 0; i < 3; i++ )
58 fields.insert( i, new QLineEdit( this ) );
59 fields[0]->setText( "Homer" );
60 fields[1]->setText( "Simpson" );
61 fields[2]->setText( "45" );
62 QIntDictIterator<QLineEdit> it( fields );
63 for ( ; it.current(); ++it )
64 cout << it.currentKey() << ": " << it.current()->text() << endl;
65 for ( int i = 0; i < 3; i++ )
66 cout << fields[i]->text() << " "; // Prints "Homer Simpson 45"
67 cout << endl;
68 fields.remove( 1 ); // Does not delete the line edit
69 for ( int i = 0; i < 3; i++ )
70 if ( fields[i] )
71 cout << fields[i]->text() << " "; // Prints "Homer 45"
72 See QDict for full details, including the choice of dictionary size,
74 and how deletions are handled.
75 See also QIntDictIterator, QDict, QAsciiDict, QPtrDict, Collection
77 Classes, Collection Classes, and Non-GUI Classes.
78
81 Constructs a dictionary using an internal hash array of size size.
82 Setting size to a suitably large prime number (equal to or greater than
84 the expected number of entries) makes the hash distribution better
85 which leads to faster lookup.
86
88 Constructs a copy of dict.
89 Each item in dict is inserted into this dictionary. Only the pointers
91 are copied (shallow copy).
92
94 Removes all items from the dictionary and destroys it.
95 All iterators that access this dictionary will be reset.
97 See also setAutoDelete().
99
101 Returns the setting of the auto-delete option. The default is FALSE.
102 See also setAutoDelete().
104
106 Removes all items from the dictionary.
107 The removed items are deleted if auto-deletion is enabled.
109 All dictionary iterators that access this dictionary will be reset.
111 See also remove(), take(), and setAutoDelete().
113 Reimplemented from QPtrCollection.
115
117 Returns the number of items in the dictionary.
118 See also isEmpty().
120 Reimplemented from QPtrCollection.
122
124 Returns the item associated with key, or 0 if the key does not exist in
125 the dictionary.
126 If there are two or more items with equal keys, then the most recently
128 inserted item will be found.
129 Equivalent to operator[].
131 See also operator[]().
133 Example: table/bigtable/main.cpp.
135
137 Insert item item into the dictionary using key key.
138 Multiple items can have the same key, in which case only the last item
140 will be accessible using operator[]().
141 item may not be 0.
143 See also replace().
145 Example: scribble/scribble.cpp.
147
149 Returns TRUE if the dictionary is empty; otherwise returns FALSE.
150 See also count().
152
154 Assigns dict to this dictionary and returns a reference to this
155 dictionary.
156 This dictionary is first cleared and then each item in dict is inserted
158 into this dictionary. Only the pointers are copied (shallow copy),
159 unless newItem() has been reimplemented.
160
162 Returns the item associated with key, or 0 if the key does not exist in
163 the dictionary.
164 If there are two or more items with equal keys, then the most recently
166 inserted item will be found.
167 Equivalent to the find() function.
169 See also find().
171
173 [virtual protected]
174 Reads a dictionary item from the stream s and returns a reference to
175 the stream.
176 The default implementation sets item to 0.
178 See also write().
180
182 Removes the item associated with key from the dictionary. Returns TRUE
183 if successful, i.e. if the key is in the dictionary; otherwise returns
184 FALSE.
185 If there are two or more items with equal keys, then the most recently
187 inserted item will be removed.
188 The removed item is deleted if auto-deletion is enabled.
190 All dictionary iterators that refer to the removed item will be set to
192 point to the next item in the dictionary's traversal order.
193 See also take(), clear(), and setAutoDelete().
195 Example: table/bigtable/main.cpp.
197
199 If the dictionary has key key, this key's item is replaced with item.
200 If the dictionary doesn't contain key key, item is inserted into the
201 dictionary using key key.
202 item may not be 0.
204 Equivalent to:
206 QIntDict<char> dict;
208 // ...
209 if ( dict.find(key) )
210 dict.remove( key );
211 dict.insert( key, item );
212 If there are two or more items with equal keys, then the most recently
214 inserted item will be replaced.
215 See also insert().
217 Example: table/bigtable/main.cpp.
219
221 Changes the size of the hashtable to newsize. The contents of the
222 dictionary are preserved, but all iterators on the dictionary become
223 invalid.
224
226 Sets the collection to auto-delete its contents if enable is TRUE and
227 to never delete them if enable is FALSE.
228 If auto-deleting is turned on, all the items in a collection are
230 deleted when the collection itself is deleted. This is convenient if
231 the collection has the only pointer to the items.
232 The default setting is FALSE, for safety. If you turn it on, be careful
234 about copying the collection - you might find yourself with two
235 collections deleting the same items.
236 Note that the auto-delete setting may also affect other functions in
238 subclasses. For example, a subclass that has a remove() function will
239 remove the item from its data structure, and if auto-delete is enabled,
240 will also delete the item.
241 See also autoDelete().
243 Examples:
245
247 Returns the size of the internal hash array (as specified in the
248 constructor).
249 See also count().
251
253 Debugging-only function that prints out the dictionary distribution
254 using qDebug().
255
257 Takes the item associated with key out of the dictionary without
258 deleting it (even if auto-deletion is enabled).
259 If there are two or more items with equal keys, then the most recently
261 inserted item will be taken.
262 Returns a pointer to the item taken out, or 0 if the key does not exist
264 in the dictionary.
265 All dictionary iterators that refer to the taken item will be set to
267 point to the next item in the dictionary's traversing order.
268 See also remove(), clear(), and setAutoDelete().
270 Example: table/bigtable/main.cpp.
272
274 [virtual protected]
275 Writes a dictionary item to the stream s and returns a reference to the
276 stream.
277 See also read().
279
282 http://doc.trolltech.com/qintdict.html
283 http://www.trolltech.com/faq/tech.html
284
286 Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com. See the
287 license file included in the distribution for a complete license
288 statement.
289
291 Generated automatically from the source code.
292
294 If you find a bug in Qt, please report it as described in
295 http://doc.trolltech.com/bughowto.html. Good bug reports help us to
296 help you. Thank you.
297 The definitive Qt documentation is provided in HTML format; it is
299 located at $QTDIR/doc/html and can be read using Qt Assistant or with a
300 web browser. This man page is provided as a convenience for those users
301 who prefer man pages, although this format is not officially supported
302 by Trolltech.
303 If you find errors in this manual page, please report them to qt-
305 bugs@trolltech.com. Please include the name of the manual page
306 (qintdict.3qt) and the Qt version (3.3.8).
307Trolltech AS 2 February 2007 QIntDict(3qt)