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<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>QValueListIterator Class Reference</h1>
<p>The QValueListIterator class provides an iterator for QValueList.
<a href="#details">More...</a>
<p><tt>#include <<a href="qvaluelist-h.html">qvaluelist.h</a>></tt>
<p><a href="qvaluelistiterator-members.html">List of all member functions.</a>
<h2>Public Members</h2>
<ul>
<li><div class=fn>typedef T <a href="#value_type"><b>value_type</b></a></div></li>
<li><div class=fn>typedef T * <a href="#pointer"><b>pointer</b></a></div></li>
<li><div class=fn>typedef T & <a href="#reference"><b>reference</b></a></div></li>
<li><div class=fn><a href="#QValueListIterator"><b>QValueListIterator</b></a> ()</div></li>
<li><div class=fn><a href="#QValueListIterator-3"><b>QValueListIterator</b></a> ( const QValueListIterator<T> & it )</div></li>
<li><div class=fn>bool <a href="#operator-eq-eq"><b>operator==</b></a> ( const QValueListIterator<T> & it ) const</div></li>
<li><div class=fn>bool <a href="#operator!-eq"><b>operator!=</b></a> ( const QValueListIterator<T> & it ) const</div></li>
<li><div class=fn>const T & <a href="#operator*-2"><b>operator*</b></a> () const</div></li>
<li><div class=fn>T & <a href="#operator*"><b>operator*</b></a> ()</div></li>
<li><div class=fn>QValueListIterator<T> & <a href="#operator++"><b>operator++</b></a> ()</div></li>
<li><div class=fn>QValueListIterator<T> <a href="#operator++-2"><b>operator++</b></a> ( int )</div></li>
<li><div class=fn>QValueListIterator<T> & <a href="#operator--"><b>operator--</b></a> ()</div></li>
<li><div class=fn>QValueListIterator<T> <a href="#operator---2"><b>operator--</b></a> ( int )</div></li>
</ul>
<hr><a name="details"></a><h2>Detailed Description</h2>
The QValueListIterator class provides an iterator for <a href="qvaluelist.html">QValueList</a>.
<p>
<p> An iterator is a class for accessing the items of a container
classes - a generalization of the index in an array. A pointer into
a "const char *" and an index into an "int[]"
are both iterators, and the general idea is to provide that
functionality for any data structure.
<p> The QValueListIterator class is an iterator for QValueList
instantiations. You can create the appropriate iterator type by
using the <tt>iterator</tt> typedef provided by QValueList.
<p> The only way to access the items in a QValueList is to use an
iterator.
<p> Example (see QValueList for the complete code):
<pre>
EmployeeList::iterator it;
for ( it = list.begin(); it != list.end(); ++it )
cout << (*it).surname().latin1() << ", " <<
(*it).forename().latin1() << " earns " <<
(*it).salary() << endl;
// Output:
// Doe, John earns 50000
// Williams, Jane earns 80000
// Hawthorne, Mary earns 90000
// Jones, Tom earns 60000
</pre>
<p> <a href="qvaluelist.html">QValueList</a> is highly optimized for performance and memory usage.
This means that you must be careful: QValueList does not know about
all its iterators and the iterators don't know to which list they
belong. This makes things very fast, but if you're not careful, you
can get spectacular bugs. Always make sure iterators are valid
before dereferencing them or using them as parameters to generic
algorithms in the STL or the <a href="qtl.html">QTL</a>.
<p> Using an invalid iterator is undefined (your application will
probably crash). Many Qt functions return const value lists; to
iterate over these you should make a copy and iterate over the copy.
<p> For every Iterator there is a ConstIterator. When accessing a
QValueList in a const environment or if the reference or pointer to
the list is itself const, then you must use the
ConstIterator. Its semantics are the same as the Iterator, but it
returns only const references.
<p> <p>See also <a href="qvaluelist.html">QValueList</a>, <a href="qvaluelistconstiterator.html">QValueListConstIterator</a>, <a href="qtl.html">Qt Template Library Classes</a> and <a href="tools.html">Non-GUI Classes</a>.
<hr><h2>Member Type Documentation</h2>
<h3 class=fn><a name="pointer"></a>QValueListIterator::pointer</h3>
Pointer to value_type.
<h3 class=fn><a name="reference"></a>QValueListIterator::reference</h3>
Reference to value_type.
<h3 class=fn><a name="value_type"></a>QValueListIterator::value_type</h3>
The type of value, T.
<hr><h2>Member Function Documentation</h2>
<h3 class=fn><a name="QValueListIterator"></a>QValueListIterator::QValueListIterator ()
</h3>
Creates un uninitialized iterator.
<h3 class=fn><a name="QValueListIterator-3"></a>QValueListIterator::QValueListIterator ( const <a href="qvaluelistiterator.html">QValueListIterator</a><T> & it )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Constructs a copy of the iterator <em>it</em>.
<h3 class=fn>bool <a name="operator!-eq"></a>QValueListIterator::operator!= ( const <a href="qvaluelistiterator.html">QValueListIterator</a><T> & it ) const
</h3>
<p> Compares this iterator and <em>it</em> and returns TRUE if they point to
different items; otherwise returns FALSE.
<h3 class=fn>T & <a name="operator*"></a>QValueListIterator::operator* ()
</h3>
<p> Asterisk operator. Returns a reference to the current iterator item.
<h3 class=fn>const T & <a name="operator*-2"></a>QValueListIterator::operator* () const
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Asterisk operator. Returns a reference to the current iterator item.
<h3 class=fn><a href="qvaluelistiterator.html">QValueListIterator</a><T> & <a name="operator++"></a>QValueListIterator::operator++ ()
</h3>
<p> Prefix ++ makes the succeeding item current and returns
an iterator pointing to the new current item.
The iterator cannot check whether it reached the end of the list. Incrementing
the iterator as returned by end() causes undefined results.
<h3 class=fn><a href="qvaluelistiterator.html">QValueListIterator</a><T> <a name="operator++-2"></a>QValueListIterator::operator++ ( int )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Postfix ++ makes the succeeding item current and returns
an iterator pointing to the new current item.
The iterator cannot check whether it reached the end of the list. Incrementing
the iterator as returned by end() causes undefined results.
<h3 class=fn><a href="qvaluelistiterator.html">QValueListIterator</a><T> & <a name="operator--"></a>QValueListIterator::operator-- ()
</h3>
<p> Prefix -- makes the previous item current and returns
an iterator pointing to the new current item.
The iterator cannot check whether it reached the beginning of the list. Decrementing
the iterator as returned by begin() causes undefined results.
<h3 class=fn><a href="qvaluelistiterator.html">QValueListIterator</a><T> <a name="operator---2"></a>QValueListIterator::operator-- ( int )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Postfix -- makes the previous item current and returns
an iterator pointing to the new current item.
The iterator cannot check whether it reached the beginning of the list. Decrementing
the iterator as returned by begin() causes undefined results.
<h3 class=fn>bool <a name="operator-eq-eq"></a>QValueListIterator::operator== ( const <a href="qvaluelistiterator.html">QValueListIterator</a><T> & it ) const
</h3>
<p> Compares this iterator and <em>it</em> and returns TRUE if they point to
the same item; otherwise returns FALSE.
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