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<td align="right" valign="top" width="230"><img src="images/trolltech-logo.png" align="right" width="203" height="32" border="0" /></td></tr></table><h1 align="center">Q3PtrListIterator Class Reference</h1>

<p>The Q3PtrListIterator class provides an iterator for <a href="q3ptrlist.html">Q3PtrList</a> collections. <a href="#details">More...</a></p>

<pre>#include <Q3PtrListIterator></pre><p><b>This class is part of the Qt 3 support library.</b> It is provided to keep old source code working. We strongly advise against using it in new code. See the <a href="porting4.html">Porting Guide</a> for more information.</p>

<p>Part of the <a href="qt3support.html">Qt3Support</a> module.</p>

<p>Inherited by <a href="q3strlistiterator.html">Q3StrListIterator</a>.</p>

<ul>

<li><a href="q3ptrlistiterator-members.html">List of all members, including inherited members</a></li>

</ul>

<h3>Public Functions</h3>

<ul>

<li><div class="fn"/><b><a href="q3ptrlistiterator.html#Q3PtrListIterator">Q3PtrListIterator</a></b> ( const Q3PtrList<type> & <i>list</i> )</li>

<li><div class="fn"/><b><a href="q3ptrlistiterator.html#dtor.Q3PtrListIterator">~Q3PtrListIterator</a></b> ()</li>

<li><div class="fn"/>bool <b><a href="q3ptrlistiterator.html#atFirst">atFirst</a></b> () const</li>

<li><div class="fn"/>bool <b><a href="q3ptrlistiterator.html#atLast">atLast</a></b> () const</li>

<li><div class="fn"/>uint <b><a href="q3ptrlistiterator.html#count">count</a></b> () const</li>

<li><div class="fn"/>type * <b><a href="q3ptrlistiterator.html#current">current</a></b> () const</li>

<li><div class="fn"/>bool <b><a href="q3ptrlistiterator.html#isEmpty">isEmpty</a></b> () const</li>

<li><div class="fn"/>type * <b><a href="q3ptrlistiterator.html#toFirst">toFirst</a></b> ()</li>

<li><div class="fn"/>type * <b><a href="q3ptrlistiterator.html#toLast">toLast</a></b> ()</li>

<li><div class="fn"/><b><a href="q3ptrlistiterator.html#operator-type--2a">operator type *</a></b> () const</li>

<li><div class="fn"/>type * <b><a href="q3ptrlistiterator.html#operator-28-29">operator()</a></b> ()</li>

<li><div class="fn"/>type * <b><a href="q3ptrlistiterator.html#operator-2a">operator*</a></b> ()</li>

<li><div class="fn"/>type * <b><a href="q3ptrlistiterator.html#operator-2b-2b">operator++</a></b> ()</li>

<li><div class="fn"/>type * <b><a href="q3ptrlistiterator.html#operator-2b-eq">operator+=</a></b> ( uint <i>jump</i> )</li>

<li><div class="fn"/>type * <b><a href="q3ptrlistiterator.html#operator--">operator--</a></b> ()</li>

<li><div class="fn"/>type * <b><a href="q3ptrlistiterator.html#operator--eq">operator-=</a></b> ( uint <i>jump</i> )</li>

<li><div class="fn"/>Q3PtrListIterator<type> & <b><a href="q3ptrlistiterator.html#operator-eq">operator=</a></b> ( const Q3PtrListIterator<type> & <i>it</i> )</li>

</ul>

<hr />

<h2>Detailed Description</h2>

<p>The Q3PtrListIterator class provides an iterator for <a href="q3ptrlist.html">Q3PtrList</a> collections.</p>

<p>Define a template instance Q3PtrListIterator<X> to create a list iterator that operates on <a href="q3ptrlist.html">Q3PtrList</a><X> (list of X*).</p>

<p>The following example is similar to the example in the <a href="q3ptrlist.html">Q3PtrList</a> class documentation, but it uses Q3PtrListIterator. The class Employee is defined there.</p>

<pre>  Q3PtrList<Employee> list;

list.append( new Employee("John", "Doe", 50000) );

list.append( new Employee("Jane", "Williams", 80000) );

list.append( new Employee("Tom", "Jones", 60000) );

Q3PtrListIterator<Employee> it( list );

Employee *employee;

while ( (employee = it.current()) != 0 ) {

++it;

cout << employee->surname().latin1() << ", " <<

employee->forename().latin1() << " earns " <<

employee->salary() << endl;

}</pre>

<p>The output is</p>

<pre>  Doe, John earns 50000

Williams, Jane earns 80000

Jones, Tom earns 60000</pre>

<p>Using a list iterator is a more robust way of traversing the list than using the <a href="q3ptrlist.html">Q3PtrList</a> member functions <a href="q3ptrlist.html#first">first</a>(), <a href="q3ptrlist.html#next">next</a>(), <a href="q3ptrlist.html#current">current</a>(), etc., as many iterators can traverse the same list independently.</p>

<p>An iterator has its own current list item and can get the next and previous list items. It doesn't modify the list in any way.</p>

<p>When an item is removed from the list, all iterators that point to that item are updated to point to <a href="q3ptrlist.html#current">Q3PtrList::current</a>() instead to avoid dangling references.</p>

<p>See also <a href="q3ptrlist.html">Q3PtrList</a>.</p>

<hr />

<h2>Member Function Documentation</h2>

<h3 class="fn"><a name="Q3PtrListIterator"></a>Q3PtrListIterator::Q3PtrListIterator ( const <a href="q3ptrlist.html">Q3PtrList</a><type> & <i>list</i> )</h3>

<p>Constructs an iterator for <i>list</i>. The current iterator item is set to point on the first item in the <i>list</i>.</p>

<h3 class="fn"><a name="dtor.Q3PtrListIterator"></a>Q3PtrListIterator::~Q3PtrListIterator ()</h3>

<p>Destroys the iterator.</p>

<h3 class="fn"><a name="atFirst"></a>bool Q3PtrListIterator::atFirst () const</h3>

<p>Returns TRUE if the current iterator item is the first list item; otherwise returns FALSE.</p>

<p>See also <a href="q3ptrlistiterator.html#toFirst">toFirst</a>() and <a href="q3ptrlistiterator.html#atLast">atLast</a>().</p>

<h3 class="fn"><a name="atLast"></a>bool Q3PtrListIterator::atLast () const</h3>

<p>Returns TRUE if the current iterator item is the last list item; otherwise returns FALSE.</p>

<p>See also <a href="q3ptrlistiterator.html#toLast">toLast</a>() and <a href="q3ptrlistiterator.html#atFirst">atFirst</a>().</p>

<h3 class="fn"><a name="count"></a><a href="qtglobal.html#uint-typedef">uint</a> Q3PtrListIterator::count () const</h3>

<p>Returns the number of items in the list this iterator operates on.</p>

<p>See also <a href="q3ptrlistiterator.html#isEmpty">isEmpty</a>().</p>

<h3 class="fn"><a name="current"></a>type * Q3PtrListIterator::current () const</h3>

<p>Returns a pointer to the current iterator item. If the iterator is positioned before the first item in the list or after the last item in the list, 0 is returned.</p>

<h3 class="fn"><a name="isEmpty"></a>bool Q3PtrListIterator::isEmpty () const</h3>

<p>Returns TRUE if the list is empty; otherwise returns FALSE.</p>

<p>See also <a href="q3ptrlistiterator.html#count">count</a>().</p>

<h3 class="fn"><a name="toFirst"></a>type * Q3PtrListIterator::toFirst ()</h3>

<p>Sets the current iterator item to point to the first list item and returns a pointer to the item. Sets the current item to 0 and returns 0 if the list is empty.</p>

<p>See also <a href="q3ptrlistiterator.html#toLast">toLast</a>() and <a href="q3ptrlistiterator.html#atFirst">atFirst</a>().</p>

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<h3 class="fn"><a name="toLast"></a>type * Q3PtrListIterator::toLast ()</h3>

101

<p>Sets the current iterator item to point to the last list item and returns a pointer to the item. Sets the current item to 0 and returns 0 if the list is empty.</p>

102

<p>See also <a href="q3ptrlistiterator.html#toFirst">toFirst</a>() and <a href="q3ptrlistiterator.html#atLast">atLast</a>().</p>

103

<h3 class="fn"><a name="operator-type--2a"></a>Q3PtrListIterator::operator type * () const</h3>

104

<p>Cast operator. Returns a pointer to the current iterator item. Same as <a href="q3ptrlistiterator.html#current">current</a>().</p>

105

<h3 class="fn"><a name="operator-28-29"></a>type * Q3PtrListIterator::operator() ()</h3>

106

<p>Makes the succeeding item current and returns the original current item.</p>

107

<p>If the current iterator item was the last item in the list or if it was 0, 0 is returned.</p>

108

<h3 class="fn"><a name="operator-2a"></a>type * Q3PtrListIterator::operator* ()</h3>

109

<p>Asterisk operator. Returns a pointer to the current iterator item. Same as <a href="q3ptrlistiterator.html#current">current</a>().</p>

110

<h3 class="fn"><a name="operator-2b-2b"></a>type * Q3PtrListIterator::operator++ ()</h3>

111

<p>Prefix ++ makes the succeeding item current and returns the new current item.</p>

112

<p>If the current iterator item was the last item in the list or if it was 0, 0 is returned.</p>

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<h3 class="fn"><a name="operator-2b-eq"></a>type * Q3PtrListIterator::operator+= ( <a href="qtglobal.html#uint-typedef">uint</a> <i>jump</i> )</h3>

114

<p>Sets the current item to the item <i>jump</i> positions after the current item and returns a pointer to that item.</p>

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<p>If that item is beyond the last item or if the list is empty, it sets the current item to 0 and returns 0</p>

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<h3 class="fn"><a name="operator--"></a>type * Q3PtrListIterator::operator-- ()</h3>

117

<p>Prefix - makes the preceding item current and returns the new current item.</p>

118

<p>If the current iterator item was the first item in the list or if it was 0, 0 is returned.</p>

119

<h3 class="fn"><a name="operator--eq"></a>type * Q3PtrListIterator::operator-= ( <a href="qtglobal.html#uint-typedef">uint</a> <i>jump</i> )</h3>

120

<p>Returns the item <i>jump</i> positions before the current item or 0 if it is beyond the first item. Makes this the current item.</p>

121

<h3 class="fn"><a name="operator-eq"></a>Q3PtrListIterator<type> & Q3PtrListIterator::operator= ( const Q3PtrListIterator<type> & <i>it</i> )</h3>

122

<p>Assignment. Makes a copy of the iterator <i>it</i> and returns a reference to this iterator.</p>

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<td width="40%" align="center"><a href="trademarks.html">Trademarks</a></td>

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