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32<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>QValueVector Class Reference</h1>
33
34<p>The QValueVector class is a value-based template class that provides a dynamic array.
35<a href="#details">More...</a>
36<p>All the functions in this class are <a href="threads.html#reentrant">reentrant</a> when Qt is built with thread support.</p>
37<p><tt>#include &lt;<a href="qvaluevector-h.html">qvaluevector.h</a>&gt;</tt>
38<p><a href="qvaluevector-members.html">List of all member functions.</a>
39<h2>Public Members</h2>
40<ul>
41<li class=fn>typedef T&nbsp;<a href="#value_type"><b>value_type</b></a></li>
42<li class=fn>typedef value_type&nbsp;*&nbsp;<a href="#pointer"><b>pointer</b></a></li>
43<li class=fn>typedef const&nbsp;value_type&nbsp;*&nbsp;<a href="#const_pointer"><b>const_pointer</b></a></li>
44<li class=fn>typedef value_type&nbsp;*&nbsp;<a href="#iterator"><b>iterator</b></a></li>
45<li class=fn>typedef const&nbsp;value_type&nbsp;*&nbsp;<a href="#const_iterator"><b>const_iterator</b></a></li>
46<li class=fn>typedef value_type&nbsp;&amp;&nbsp;<a href="#reference"><b>reference</b></a></li>
47<li class=fn>typedef const&nbsp;value_type&nbsp;&amp;&nbsp;<a href="#const_reference"><b>const_reference</b></a></li>
48<li class=fn>typedef size_t&nbsp;<a href="#size_type"><b>size_type</b></a></li>
49<li class=fn>typedef ptrdiff_t&nbsp;<a href="#difference_type"><b>difference_type</b></a></li>
50<li class=fn><a href="#QValueVector"><b>QValueVector</b></a> ()</li>
51<li class=fn><a href="#QValueVector-2"><b>QValueVector</b></a> ( const&nbsp;QValueVector&lt;T&gt;&nbsp;&amp;&nbsp;v )</li>
52<li class=fn><a href="#QValueVector-3"><b>QValueVector</b></a> ( size_type&nbsp;n, const&nbsp;T&nbsp;&amp;&nbsp;val = T ( ) )</li>
53<li class=fn><a href="#QValueVector-4"><b>QValueVector</b></a> ( std::vector&lt;T&gt;&nbsp;&amp;&nbsp;v )</li>
54<li class=fn><a href="#QValueVector-5"><b>QValueVector</b></a> ( const&nbsp;std::vector&lt;T&gt;&nbsp;&amp;&nbsp;v )</li>
55<li class=fn><a href="#~QValueVector"><b>~QValueVector</b></a> ()</li>
56<li class=fn>QValueVector&lt;T&gt; &amp; <a href="#operator-eq"><b>operator=</b></a> ( const&nbsp;QValueVector&lt;T&gt;&nbsp;&amp;&nbsp;v )</li>
57<li class=fn>QValueVector&lt;T&gt; &amp; <a href="#operator-eq-2"><b>operator=</b></a> ( const&nbsp;std::vector&lt;T&gt;&nbsp;&amp;&nbsp;v )</li>
58<li class=fn>size_type <a href="#size"><b>size</b></a> () const</li>
59<li class=fn>bool <a href="#empty"><b>empty</b></a> () const</li>
60<li class=fn>size_type <a href="#capacity"><b>capacity</b></a> () const</li>
61<li class=fn>iterator <a href="#begin"><b>begin</b></a> ()</li>
62<li class=fn>const_iterator <a href="#begin-2"><b>begin</b></a> () const</li>
63<li class=fn>const_iterator <a href="#constBegin"><b>constBegin</b></a> () const</li>
64<li class=fn>iterator <a href="#end"><b>end</b></a> ()</li>
65<li class=fn>const_iterator <a href="#end-2"><b>end</b></a> () const</li>
66<li class=fn>const_iterator <a href="#constEnd"><b>constEnd</b></a> () const</li>
67<li class=fn>reference <a href="#at"><b>at</b></a> ( size_type&nbsp;i, bool&nbsp;*&nbsp;ok = 0 )</li>
68<li class=fn>const_reference <a href="#at-2"><b>at</b></a> ( size_type&nbsp;i, bool&nbsp;*&nbsp;ok = 0 ) const</li>
69<li class=fn>reference <a href="#operator[]"><b>operator[]</b></a> ( size_type&nbsp;i )</li>
70<li class=fn>const_reference <a href="#operator[]-2"><b>operator[]</b></a> ( size_type&nbsp;i ) const</li>
71<li class=fn>reference <a href="#front"><b>front</b></a> ()</li>
72<li class=fn>const_reference <a href="#front-2"><b>front</b></a> () const</li>
73<li class=fn>reference <a href="#back"><b>back</b></a> ()</li>
74<li class=fn>const_reference <a href="#back-2"><b>back</b></a> () const</li>
75<li class=fn>void <a href="#push_back"><b>push_back</b></a> ( const&nbsp;T&nbsp;&amp;&nbsp;x )</li>
76<li class=fn>void <a href="#pop_back"><b>pop_back</b></a> ()</li>
77<li class=fn>iterator <a href="#insert"><b>insert</b></a> ( iterator&nbsp;pos, const&nbsp;T&nbsp;&amp;&nbsp;x )</li>
78<li class=fn>iterator <a href="#insert-2"><b>insert</b></a> ( iterator&nbsp;pos, size_type&nbsp;n, const&nbsp;T&nbsp;&amp;&nbsp;x )</li>
79<li class=fn>void <a href="#reserve"><b>reserve</b></a> ( size_type&nbsp;n )</li>
80<li class=fn>void <a href="#resize"><b>resize</b></a> ( size_type&nbsp;n, const&nbsp;T&nbsp;&amp;&nbsp;val = T ( ) )</li>
81<li class=fn>void <a href="#clear"><b>clear</b></a> ()</li>
82<li class=fn>iterator <a href="#erase"><b>erase</b></a> ( iterator&nbsp;pos )</li>
83<li class=fn>iterator <a href="#erase-2"><b>erase</b></a> ( iterator&nbsp;first, iterator&nbsp;last )</li>
84<li class=fn>bool <a href="#operator-eq-eq-2"><b>operator==</b></a> ( const&nbsp;QValueVector&lt;T&gt;&nbsp;&amp;&nbsp;x )</li>
85<li class=fn>bool <a href="#operator-eq-eq"><b>operator==</b></a> ( const&nbsp;QValueVector&lt;T&gt;&nbsp;&amp;&nbsp;x ) const</li>
86<li class=fn>typedef T&nbsp;<a href="#ValueType"><b>ValueType</b></a></li>
87<li class=fn>typedef ValueType&nbsp;*&nbsp;<a href="#Iterator"><b>Iterator</b></a></li>
88<li class=fn>typedef const&nbsp;ValueType&nbsp;*&nbsp;<a href="#ConstIterator"><b>ConstIterator</b></a></li>
89<li class=fn>size_type <a href="#count"><b>count</b></a> () const</li>
90<li class=fn>bool <a href="#isEmpty"><b>isEmpty</b></a> () const</li>
91<li class=fn>reference <a href="#first"><b>first</b></a> ()</li>
92<li class=fn>const_reference <a href="#first-2"><b>first</b></a> () const</li>
93<li class=fn>reference <a href="#last"><b>last</b></a> ()</li>
94<li class=fn>const_reference <a href="#last-2"><b>last</b></a> () const</li>
95<li class=fn>void <a href="#append"><b>append</b></a> ( const&nbsp;T&nbsp;&amp;&nbsp;x )</li>
96</ul>
97<hr><a name="details"></a><h2>Detailed Description</h2>
98
99
100The QValueVector class is a value-based template class that provides a dynamic array.
101<p>
102
103
104
105
106<p> QValueVector is a Qt implementation of an STL-like vector
107container. It can be used in your application if the standard <tt>vector</tt> is not available for your target platforms. QValueVector is
108part of the <a href="qtl.html">Qt Template Library</a>.
109<p> QValueVector&lt;T&gt; defines a template instance to create a vector
110of values that all have the class T. QValueVector does not store
111pointers to the members of the vector; it holds a copy of every
112member. QValueVector is said to be value based; in contrast,
113<a href="qptrlist.html">QPtrList</a> and <a href="qdict.html">QDict</a> are pointer based.
114<p> QValueVector contains and manages a collection of objects of type
115T and provides random access iterators that allow the contained
116objects to be addressed. QValueVector owns the contained
117elements. For more relaxed ownership semantics, see <a href="qptrcollection.html">QPtrCollection</a>
118and friends, which are pointer-based containers.
119<p> QValueVector provides good performance if you append or remove
120elements from the end of the vector. If you insert or remove
121elements from anywhere but the end, performance is very bad. The
122reason for this is that elements must to be copied into new
123positions.
124<p> Some classes cannot be used within a QValueVector: for example,
125all classes derived from <a href="qobject.html">QObject</a> and thus all classes that
126implement widgets. Only values can be used in a QValueVector. To
127qualify as a value the class must provide:
128<ul>
129<li> a copy constructor;
130<li> an assignment operator;
131<li> a default constructor, i.e., a constructor that does not take any arguments.
132</ul>
133<p> Note that C++ defaults to field-by-field assignment operators and
134copy constructors if no explicit version is supplied. In many
135cases this is sufficient.
136<p> QValueVector uses an STL-like syntax to manipulate and address the
137objects it contains. See <a href="qtl.html">this document</a> for
138more information.
139<p> Example:
140<pre>
141 #include &lt;<a href="qvaluevector-h.html">qvaluevector.h</a>&gt;
142 #include &lt;<a href="qstring-h.html">qstring.h</a>&gt;
143 #include &lt;stdio.h&gt;
144
145 class Employee
146 {
147 public:
148 Employee(): s(0) {}
149 Employee( const <a href="qstring.html">QString</a>&amp; name, int salary )
150 : n( name ), s( salary )
151 { }
152
153 <a href="qstring.html">QString</a> name() const { return n; }
154 int salary() const { return s; }
155 void setSalary( int salary ) { s = salary; }
156 private:
157 <a href="qstring.html">QString</a> n;
158 int s;
159 };
160
161 int main()
162 {
163 typedef QValueVector&lt;Employee&gt; EmployeeVector;
164 EmployeeVector vec( 3 ); // vector of 3 Employees
165
166 vec[0] = Employee( "Bill", 50000 );
167 vec[1] = Employee( "Steve", 80000 );
168 vec[2] = Employee( "Ron", 60000 );
169
170 Employee joe( "Joe", 50000 );
171 vec.push_back( joe ); // vector expands to accommodate 4 Employees
172 joe.setSalary( 70000 );
173
174 EmployeeVector::<a href="#iterator">iterator</a> it;
175 for( it = vec.begin(); it != vec.end(); ++it )
176 printf( "%s earns %d\n", (*it).name().latin1(), (*it).salary() );
177
178 return 0;
179 }
180 </pre>
181
182<p> Program output:
183<pre>
184 Bill earns 50000
185 Steve earns 80000
186 Ron earns 60000
187 Joe earns 50000
188 </pre>
189
190<p> As you can see, the most recent change to Joe's salary did not
191affect the value in the vector because the vector created a copy
192of Joe's entry.
193<p> Many Qt functions return const value vectors; to iterate over
194these you should make a copy and iterate over the copy.
195<p> There are several ways to find items in the vector. The <a href="#begin">begin</a>()
196and <a href="#end">end</a>() functions return iterators to the beginning and end of
197the vector. The advantage of getting an iterator is that you can
198move forward or backward from this position by
199incrementing/decrementing the iterator. The iterator returned by
200end() points to the element which is one past the last element in
201the container. The past-the-end iterator is still associated with
202the vector it belongs to, however it is <em>not</em> dereferenceable;
203<a href="qsize.html#operator*-4">operator*</a>() will not return a well-defined value. If the vector is
204<a href="#empty">empty</a>(), the iterator returned by begin() will equal the iterator
205returned by end().
206<p> The fastest way to access an element of a vector is by using
207operator[]. This function provides random access and will return
208a reference to the element located at the specified index. Thus,
209you can access every element directly, in constant time, providing
210you know the location of the element. It is undefined to access
211an element that does not exist (your application will probably
212crash). For example:
213<p> <pre>
214 QValueVector&lt;int&gt; vec1; // an empty vector
215 vec1[10] = 4; // WARNING: undefined, probably a crash
216
217 QValueVector&lt;QString&gt; vec2(25); // initialize with 25 elements
218 vec2[10] = "Dave"; // OK
219 </pre>
220
221<p> Whenever inserting, removing or referencing elements in a vector,
222always make sure you are referring to valid positions. For
223example:
224<p> <pre>
225 void func( QValueVector&lt;int&gt;&amp; vec )
226 {
227 if ( vec.<a href="#size">size</a>() &gt; 10 ) {
228 vec[9] = 99; // OK
229 }
230 };
231 </pre>
232
233<p> The iterators provided by vector are random access iterators,
234therefore you can use them with many generic algorithms, for
235example, algorithms provided by the STL or the <a href="qtl.html">QTL</a>.
236<p> Another way to find an element in the vector is by using the
237std::find() or <a href="qtl.html#qFind">qFind()</a> algorithms.
238For example:
239<p> <pre>
240 QValueVector&lt;int&gt; vec;
241 ...
242 QValueVector&lt;int&gt;::<a href="#const_iterator">const_iterator</a> it = qFind( vec.<a href="#begin">begin</a>(), vec.<a href="#end">end</a>(), 3 );
243 if ( it != vector.end() )
244 // 'it' points to the found element
245 </pre>
246
247<p> It is safe to have multiple iterators on the vector at the same
248time. Since QValueVector manages memory dynamically, all iterators
249can become invalid if a memory reallocation occurs. For example,
250if some member of the vector is removed, iterators that point to
251the removed element and to all following elements become
252invalidated. Inserting into the middle of the vector will
253invalidate all iterators. For convenience, the function <a href="#back">back</a>()
254returns a reference to the last element in the vector, and <a href="#front">front</a>()
255returns a reference to the first element. If the vector is
256<a href="#empty">empty</a>(), both back() and front() have undefined behavior (your
257application will crash or do unpredictable things). Use back() and
258front() with caution, for example:
259<p> <pre>
260 QValueVector&lt;int&gt; vec( 3 );
261 vec.<a href="#push_back">push_back</a>( 1 );
262 vec.<a href="#push_back">push_back</a>( 2 );
263 vec.<a href="#push_back">push_back</a>( 3 );
264 ...
265 if ( !vec.<a href="#empty">empty</a>() ) {
266 // OK: modify the first element
267 int&amp; i = vec.<a href="#front">front</a>();
268 i = 18;
269 }
270 ...
271 QValueVector&lt;double&gt; dvec;
272 double d = dvec.<a href="#back">back</a>(); // undefined behavior
273 </pre>
274
275<p> Because QValueVector manages memory dynamically, it is recommended
276that you contruct a vector with an initial size. Inserting and
277removing elements happens fastest when:
278<ul>
279<li> Inserting or removing elements happens at the <a href="#end">end</a>() of the
280vector;
281<li> The vector does not need to allocate additional memory.
282</ul>
283<p> By creating a QValueVector with a sufficiently large initial size,
284there will be less memory allocations. Do not use an initial size
285that is too big, since it will still take time to construct all
286the empty entries, and the extra space will be wasted if it is
287never used.
288<p> Because QValueVector is value-based there is no need to be careful
289about deleting elements in the vector. The vector holds its own
290copies and will free them if the corresponding member or the
291vector itself is deleted. You can force the vector to free all of
292its items with <a href="#clear">clear</a>().
293<p> QValueVector is <a href="shclass.html#shared-implicitly">shared implicitly</a>, which means it can be copied in
294constant time. If multiple QValueVector instances share the same
295data and one needs to modify its contents, this modifying instance
296makes a copy and modifies its private copy; it thus does not
297affect the other instances. This is often called "copy on write".
298If a QValueVector is being used in a multi-threaded program, you
299must protect all access to the vector. See <a href="qmutex.html">QMutex</a>.
300<p> There are several ways to insert elements into the vector. The
301<a href="#push_back">push_back</a>() function insert elements into the end of the vector,
302and is usually fastest. The <a href="#insert">insert</a>() function can be used to add
303elements at specific positions within the vector.
304<p> Items can be also be removed from the vector in several ways.
305There are several variants of the <a href="#erase">erase</a>() function which removes a
306specific element, or range of elements, from the vector.
307<p> Vectors can be also sorted with various STL algorithms , or it can
308be sorted using the <a href="qtl.html">Qt Template Library</a>.
309For example with qHeapSort():
310<p> Example:
311<pre>
312 QValueVector&lt;int&gt; v( 4 );
313 v.<a href="#push_back">push_back</a>( 5 );
314 v.<a href="#push_back">push_back</a>( 8 );
315 v.<a href="#push_back">push_back</a>( 3 );
316 v.<a href="#push_back">push_back</a>( 4 );
317 qHeapSort( v );
318 </pre>
319
320<p> QValueVector stores its elements in contiguous memory. This means
321that you can use a QValueVector in any situation that requires an
322array.
323<p>See also <a href="qtl.html">Qt Template Library Classes</a>, <a href="shared.html">Implicitly and Explicitly Shared Classes</a>, and <a href="tools.html">Non-GUI Classes</a>.
324
325<hr><h2>Member Type Documentation</h2>
326<h3 class=fn><a name="ConstIterator"></a>QValueVector::ConstIterator</h3>
327The vector's const iterator type.
328<h3 class=fn><a name="Iterator"></a>QValueVector::Iterator</h3>
329The vector's iterator type.
330<h3 class=fn><a name="ValueType"></a>QValueVector::ValueType</h3>
331The type of the object stored in the vector.
332<h3 class=fn><a name="const_iterator"></a>QValueVector::const_iterator</h3>
333The vector's const iterator type.
334<h3 class=fn><a name="const_pointer"></a>QValueVector::const_pointer</h3>
335The const pointer to T type.
336<h3 class=fn><a name="const_reference"></a>QValueVector::const_reference</h3>
337The const reference to T type.
338<h3 class=fn><a name="difference_type"></a>QValueVector::difference_type</h3>
339A signed integral type used to represent the distance between two iterators.
340<h3 class=fn><a name="iterator"></a>QValueVector::iterator</h3>
341The vector's iterator type.
342<h3 class=fn><a name="pointer"></a>QValueVector::pointer</h3>
343The pointer to T type.
344<h3 class=fn><a name="reference"></a>QValueVector::reference</h3>
345The reference to T type.
346<h3 class=fn><a name="size_type"></a>QValueVector::size_type</h3>
347An unsigned integral type, used to represent various sizes.
348<h3 class=fn><a name="value_type"></a>QValueVector::value_type</h3>
349The type of the object stored in the vector.
350<hr><h2>Member Function Documentation</h2>
351<h3 class=fn><a name="QValueVector"></a>QValueVector::QValueVector ()
352</h3>
353
354<p> Constructs an empty vector without any elements. To create a
355vector which reserves an initial amount of space for elements, use
356<tt>QValueVector(size_type n)</tt>.
357
358<h3 class=fn><a name="QValueVector-2"></a>QValueVector::QValueVector ( const&nbsp;<a href="qvaluevector.html">QValueVector</a>&lt;T&gt;&nbsp;&amp;&nbsp;v )
359</h3>
360
361<p> Constructs a copy of <em>v</em>.
362<p> This operation costs O(1) time because QValueVector is <a href="shclass.html#implicitly-shared">implicitly shared</a>.
363<p> The first modification to the vector does takes O(n) time, because
364the elements must be copied.
365
366<h3 class=fn><a name="QValueVector-3"></a>QValueVector::QValueVector ( <a href="qvaluevector.html#size_type">size_type</a>&nbsp;n, const&nbsp;T&nbsp;&amp;&nbsp;val = T ( ) )
367</h3>
368
369<p> Constructs a vector with an initial size of <em>n</em> elements. Each
370element is initialized with the value of <em>val</em>.
371
372<h3 class=fn><a name="QValueVector-4"></a>QValueVector::QValueVector ( std::vector&lt;T&gt;&nbsp;&amp;&nbsp;v )
373</h3>
374
375<p> Constructs a copy of <em>v</em>.
376
377<h3 class=fn><a name="QValueVector-5"></a>QValueVector::QValueVector ( const&nbsp;std::vector&lt;T&gt;&nbsp;&amp;&nbsp;v )
378</h3>
379
380<p> This operation costs O(n) time because <em>v</em> is copied.
381
382<h3 class=fn><a name="~QValueVector"></a>QValueVector::~QValueVector ()
383</h3>
384
385<p> Destroys the vector, destroying all elements and freeing the
386allocated memory. References to the values in the vector and all
387iterators of this vector become invalidated. Note that it is
388impossible for an iterator to check whether or not it is valid:
389QValueVector is tuned for performance, not for error checking.
390
391<h3 class=fn>void <a name="append"></a>QValueVector::append ( const&nbsp;T&nbsp;&amp;&nbsp;x )
392</h3>
393
394<p> Appends a copy of <em>x</em> to the end of the vector.
395<p> <p>See also <a href="#push_back">push_back</a>() and <a href="#insert">insert</a>().
396
397<h3 class=fn><a href="qvaluevector.html#reference">reference</a> <a name="at"></a>QValueVector::at ( <a href="qvaluevector.html#size_type">size_type</a>&nbsp;i, bool&nbsp;*&nbsp;ok = 0 )
398</h3>
399
400<p> Returns a reference to the element with index <em>i</em>. If <em>ok</em> is
401non-null, and the index <em>i</em> is out of range, *<em>ok</em> is set to
402FALSE and the returned reference is undefined. If the index <em>i</em>
403is within the range of the vector, and <em>ok</em> is non-null, *<em>ok</em>
404is set to TRUE and the returned reference is well defined.
405
406<h3 class=fn><a href="qvaluevector.html#const_reference">const_reference</a> <a name="at-2"></a>QValueVector::at ( <a href="qvaluevector.html#size_type">size_type</a>&nbsp;i, bool&nbsp;*&nbsp;ok = 0 ) const
407</h3>
408
409<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
410<p> Returns a const reference to the element with index <em>i</em>. If <em>ok</em>
411is non-null, and the index <em>i</em> is out of range, *<em>ok</em> is set to
412FALSE and the returned reference is undefined. If the index <em>i</em>
413is within the range of the vector, and <em>ok</em> is non-null, *<em>ok</em>
414is set to TRUE and the returned reference is well defined.
415
416<h3 class=fn><a href="qvaluevector.html#reference">reference</a> <a name="back"></a>QValueVector::back ()
417</h3>
418
419<p> Returns a reference to the last element in the vector. If there is
420no last element, this function has undefined behavior.
421<p> <p>See also <a href="#empty">empty</a>() and <a href="#front">front</a>().
422
423<h3 class=fn><a href="qvaluevector.html#const_reference">const_reference</a> <a name="back-2"></a>QValueVector::back () const
424</h3>
425
426<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
427<p> Returns a const reference to the last element in the vector. If
428there is no last element, this function has undefined behavior.
429<p> <p>See also <a href="#empty">empty</a>() and <a href="#front">front</a>().
430
431<h3 class=fn><a href="qvaluevector.html#iterator">iterator</a> <a name="begin"></a>QValueVector::begin ()
432</h3>
433
434<p> Returns an iterator pointing to the beginning of the vector. If
435the vector is <a href="#empty">empty</a>(), the returned iterator will equal <a href="#end">end</a>().
436
437<h3 class=fn><a href="qvaluevector.html#const_iterator">const_iterator</a> <a name="begin-2"></a>QValueVector::begin () const
438</h3>
439
440<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
441<p> Returns a const iterator pointing to the beginning of the vector.
442If the vector is <a href="#empty">empty</a>(), the returned iterator will equal <a href="#end">end</a>().
443
444<h3 class=fn><a href="qvaluevector.html#size_type">size_type</a> <a name="capacity"></a>QValueVector::capacity () const
445</h3>
446
447<p> Returns the maximum number of elements that can be stored in the
448vector without forcing memory reallocation. If memory reallocation
449takes place, some or all iterators may become invalidated.
450
451<h3 class=fn>void <a name="clear"></a>QValueVector::clear ()
452</h3>
453
454<p> Removes all the elements from the vector.
455
456<h3 class=fn><a href="qvaluevector.html#const_iterator">const_iterator</a> <a name="constBegin"></a>QValueVector::constBegin () const
457</h3>
458
459<p> Returns a const iterator pointing to the beginning of the vector.
460If the vector is <a href="#empty">empty</a>(), the returned iterator will equal <a href="#end">end</a>().
461<p> <p>See also <a href="#constEnd">constEnd</a>().
462
463<h3 class=fn><a href="qvaluevector.html#const_iterator">const_iterator</a> <a name="constEnd"></a>QValueVector::constEnd () const
464</h3>
465
466<p> Returns a const iterator pointing behind the last element of the
467vector.
468<p> <p>See also <a href="#constBegin">constBegin</a>().
469
470<h3 class=fn><a href="qvaluevector.html#size_type">size_type</a> <a name="count"></a>QValueVector::count () const
471</h3>
472
473<p> Returns the number of items in the vector.
474<p> <p>See also <a href="#isEmpty">isEmpty</a>().
475
476<h3 class=fn>bool <a name="empty"></a>QValueVector::empty () const
477</h3>
478
479<p> Returns TRUE if the vector is empty; otherwise returns FALSE.
480Equivalent to <a href="#size">size</a>()==0, only faster.
481<p> This function is provided for STL compatibility. It is equivalent
482to <a href="#isEmpty">isEmpty</a>().
483<p> <p>See also <a href="#size">size</a>().
484
485<h3 class=fn><a href="qvaluevector.html#iterator">iterator</a> <a name="end"></a>QValueVector::end ()
486</h3>
487
488<p> Returns an iterator pointing behind the last element of the
489vector.
490
491<h3 class=fn><a href="qvaluevector.html#const_iterator">const_iterator</a> <a name="end-2"></a>QValueVector::end () const
492</h3>
493
494<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
495<p> Returns a const iterator pointing behind the last element of the
496vector.
497
498<h3 class=fn><a href="qvaluevector.html#iterator">iterator</a> <a name="erase"></a>QValueVector::erase ( <a href="qvaluevector.html#iterator">iterator</a>&nbsp;pos )
499</h3>
500
501<p> Removes the element at position <em>pos</em> and returns the position of
502the next element.
503
504<h3 class=fn><a href="qvaluevector.html#iterator">iterator</a> <a name="erase-2"></a>QValueVector::erase ( <a href="qvaluevector.html#iterator">iterator</a>&nbsp;first, <a href="qvaluevector.html#iterator">iterator</a>&nbsp;last )
505</h3>
506
507<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
508<p> Removes all elements from <em>first</em> up to but not including <em>last</em>
509and returns the position of the next element.
510
511<h3 class=fn><a href="qvaluevector.html#reference">reference</a> <a name="first"></a>QValueVector::first ()
512</h3>
513
514<p> Returns a reference to the first item in the vector. If there is
515no first item, this function has undefined behavior.
516<p> <p>See also <a href="#empty">empty</a>() and <a href="#last">last</a>().
517
518<h3 class=fn><a href="qvaluevector.html#const_reference">const_reference</a> <a name="first-2"></a>QValueVector::first () const
519</h3>
520
521<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
522<p>
523<h3 class=fn><a href="qvaluevector.html#reference">reference</a> <a name="front"></a>QValueVector::front ()
524</h3>
525
526<p> Returns a reference to the first element in the vector. If there
527is no first element, this function has undefined behavior.
528<p> <p>See also <a href="#empty">empty</a>() and <a href="#back">back</a>().
529
530<h3 class=fn><a href="qvaluevector.html#const_reference">const_reference</a> <a name="front-2"></a>QValueVector::front () const
531</h3>
532
533<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
534<p> Returns a const reference to the first element in the vector. If
535there is no first element, this function has undefined behavior.
536<p> <p>See also <a href="#empty">empty</a>() and <a href="#back">back</a>().
537
538<h3 class=fn><a href="qvaluevector.html#iterator">iterator</a> <a name="insert"></a>QValueVector::insert ( <a href="qvaluevector.html#iterator">iterator</a>&nbsp;pos, const&nbsp;T&nbsp;&amp;&nbsp;x )
539</h3>
540
541<p> Inserts a copy of <em>x</em> at the position immediately before <em>pos</em>.
542<p> <p>See also <a href="#push_back">push_back</a>().
543
544<h3 class=fn><a href="qvaluevector.html#iterator">iterator</a> <a name="insert-2"></a>QValueVector::insert ( <a href="qvaluevector.html#iterator">iterator</a>&nbsp;pos, <a href="qvaluevector.html#size_type">size_type</a>&nbsp;n, const&nbsp;T&nbsp;&amp;&nbsp;x )
545</h3>
546
547<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
548<p> Inserts <em>n</em> copies of <em>x</em> immediately before position x.
549<p> <p>See also <a href="#push_back">push_back</a>().
550
551<h3 class=fn>bool <a name="isEmpty"></a>QValueVector::isEmpty () const
552</h3>
553
554<p> Returns TRUE if the vector is empty; returns FALSE otherwise.
555<p> <p>See also <a href="#count">count</a>().
556
557<h3 class=fn><a href="qvaluevector.html#reference">reference</a> <a name="last"></a>QValueVector::last ()
558</h3>
559
560<p> Returns a reference to the last item in the vector. If there is no
561last item, this function has undefined behavior.
562<p> <p>See also <a href="#empty">empty</a>() and <a href="#first">first</a>().
563
564<h3 class=fn><a href="qvaluevector.html#const_reference">const_reference</a> <a name="last-2"></a>QValueVector::last () const
565</h3>
566
567<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
568<p>
569<h3 class=fn><a href="qvaluevector.html">QValueVector</a>&lt;T&gt;&nbsp;&amp; <a name="operator-eq"></a>QValueVector::operator= ( const&nbsp;<a href="qvaluevector.html">QValueVector</a>&lt;T&gt;&nbsp;&amp;&nbsp;v )
570</h3>
571
572<p> Assigns <em>v</em> to this vector and returns a reference to this vector.
573<p> All iterators of the current vector become invalidated by this
574operation. The cost of such an assignment is O(1) since
575QValueVector is <a href="shclass.html#implicitly-shared">implicitly shared</a>.
576
577<h3 class=fn><a href="qvaluevector.html">QValueVector</a>&lt;T&gt;&nbsp;&amp; <a name="operator-eq-2"></a>QValueVector::operator= ( const&nbsp;std::vector&lt;T&gt;&nbsp;&amp;&nbsp;v )
578</h3>
579
580<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
581<p> Assigns <em>v</em> to this vector and returns a reference to this vector.
582<p> All iterators of the current vector become invalidated by this
583operation. The cost of this assignment is O(n) since <em>v</em> is
584copied.
585
586<h3 class=fn>bool <a name="operator-eq-eq"></a>QValueVector::operator== ( const&nbsp;<a href="qvaluevector.html">QValueVector</a>&lt;T&gt;&nbsp;&amp;&nbsp;x ) const
587</h3>
588
589<p> Returns TRUE if each element in this vector equals each
590corresponding element in <em>x</em>; otherwise returns FALSE.
591
592<h3 class=fn>bool <a name="operator-eq-eq-2"></a>QValueVector::operator== ( const&nbsp;<a href="qvaluevector.html">QValueVector</a>&lt;T&gt;&nbsp;&amp;&nbsp;x )
593</h3>
594
595<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
596<p> Returns TRUE if each element in this vector equals each
597corresponding element in <em>x</em>; otherwise returns FALSE.
598
599<h3 class=fn><a href="qvaluevector.html#reference">reference</a> <a name="operator[]"></a>QValueVector::operator[] ( <a href="qvaluevector.html#size_type">size_type</a>&nbsp;i )
600</h3>
601
602<p> Returns a reference to the element at index <em>i</em>. If <em>i</em> is out
603of range, this function has undefined behavior.
604<p> <p>See also <a href="#at">at</a>().
605
606<h3 class=fn><a href="qvaluevector.html#const_reference">const_reference</a> <a name="operator[]-2"></a>QValueVector::operator[] ( <a href="qvaluevector.html#size_type">size_type</a>&nbsp;i ) const
607</h3>
608
609<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
610<p> Returns a const reference to the element at index <em>i</em>. If <em>i</em> is
611out of range, this function has undefined behavior.
612<p> <p>See also <a href="#at">at</a>().
613
614<h3 class=fn>void <a name="pop_back"></a>QValueVector::pop_back ()
615</h3>
616
617<p> Removes the last item from the vector.
618<p> This function is provided for STL compatibility.
619
620<h3 class=fn>void <a name="push_back"></a>QValueVector::push_back ( const&nbsp;T&nbsp;&amp;&nbsp;x )
621</h3>
622
623<p> Appends a copy of <em>x</em> to the end of the vector. This is the
624fastest way to add new elements.
625<p> This function is provided for STL compatibility. It is equivalent
626to <a href="#append">append</a>().
627<p> <p>See also <a href="#insert">insert</a>().
628
629<h3 class=fn>void <a name="reserve"></a>QValueVector::reserve ( <a href="qvaluevector.html#size_type">size_type</a>&nbsp;n )
630</h3>
631
632<p> Increases the vector's capacity. If <em>n</em> is less than or equal to
633<a href="#capacity">capacity</a>(), nothing happens. Otherwise, additional memory is
634allocated so that capacity() will be increased to a value greater
635than or equal to <em>n</em>. All iterators will then become invalidated.
636Note that the vector's <a href="#size">size</a>() and the values of existing elements
637remain unchanged.
638
639<h3 class=fn>void <a name="resize"></a>QValueVector::resize ( <a href="qvaluevector.html#size_type">size_type</a>&nbsp;n, const&nbsp;T&nbsp;&amp;&nbsp;val = T ( ) )
640</h3>
641
642<p> Changes the size of the vector to <em>n</em>. If <em>n</em> is greater than
643the current <a href="#size">size</a>(), elements are added to the end and initialized
644with the value of <em>val</em>. If <em>n</em> is less than size(), elements
645are removed from the end. If <em>n</em> is equal to size() nothing
646happens.
647
648<h3 class=fn><a href="qvaluevector.html#size_type">size_type</a> <a name="size"></a>QValueVector::size () const
649</h3>
650
651<p> Returns the number of elements in the vector.
652<p> This function is provided for STL compatibility. It is equivalent
653to <a href="#count">count</a>().
654<p> <p>See also <a href="#empty">empty</a>().
655
656<!-- eof -->
657<hr><p>
658This file is part of the <a href="index.html">Qt toolkit</a>.
659Copyright &copy; 1995-2007
660<a href="http://www.trolltech.com/">Trolltech</a>. All Rights Reserved.<p><address><hr><div align=center>
661<table width=100% cellspacing=0 border=0><tr>
662<td>Copyright &copy; 2007
663<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a>
664<td align=right><div align=right>Qt 3.3.8</div>
665</table></div></address></body>
666</html>
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