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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">QMutableLinkedListIterator Class Reference<br /><sup><sup>[<a href="qtcore.html">QtCore</a> module]</sup></sup></h1>

<td align="right" valign="top" width="230"><a href="http://www.trolltech.com"><img src="images/trolltech-logo.png" align="right" width="203" height="32" border="0" /></a></td></tr></table><h1 align="center">QMutableLinkedListIterator Class Reference<br /><sup><sup>[<a href="qtcore.html">QtCore</a> module]</sup></sup></h1>

<p>The QMutableLinkedListIterator class provides a Java-style non-const iterator for <a href="qlinkedlist.html">QLinkedList</a>. <a href="#details">More...</a></p>

<pre>#include <QMutableLinkedListIterator></pre><ul>

<pre> #include <QMutableLinkedListIterator></pre><ul>

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

</ul>

<p><a href="qlinkedlist.html">QLinkedList</a> has both <a href="containers.html#java-style-iterators">Java-style iterators</a> and <a href="containers.html#stl-style-iterators">STL-style iterators</a>. The Java-style iterators are more high-level and easier to use than the STL-style iterators; on the other hand, they are slightly less efficient.</p>

<p>QMutableLinkedListIterator<T> allows you to iterate over a <a href="qlinkedlist.html">QLinkedList</a><T> and modify the list. If you don't want to modify the list (or have a const <a href="qlinkedlist.html">QLinkedList</a>), use the slightly faster <a href="qlinkedlistiterator.html">QLinkedListIterator</a><T> instead.</p>

<p>The QMutableLinkedListIterator constructor takes a <a href="qlinkedlist.html">QLinkedList</a> as argument. After construction, the iterator is located at the very beginning of the list (before the first item). Here's how to iterate over all the elements sequentially:</p>

<pre>  QLinkedList<float> list;

...

QMutableLinkedListIterator<float> i(list);

while (i.hasNext())

qDebug() << i.next();</pre>

<pre> QLinkedList<float> list;

...

QMutableLinkedListIterator<float> i(list);

while (i.hasNext())

qDebug() << i.next();</pre>

<p>The <a href="qmutablelinkedlistiterator.html#next">next</a>() function returns the next item in the list and advances the iterator. Unlike STL-style iterators, Java-style iterators point <i>between</i> items rather than directly <i>at</i> items. The first call to <a href="qmutablelinkedlistiterator.html#next">next</a>() advances the iterator to the position between the first and second item, and returns the first item; the second call to <a href="qmutablelinkedlistiterator.html#next">next</a>() advances the iterator to the position between the second and third item, returning the second item; and so on.</p>

<p align="center"><img src="images/javaiterators1.png" /></p><p>Here's how to iterate over the elements in reverse order:</p>

<pre>  QMutableLinkedListIterator<float> i(list);

i.toBack();

while (i.hasPrevious())

qDebug() << i.previous();</pre>

<pre> QMutableLinkedListIterator<float> i(list);

i.toBack();

while (i.hasPrevious())

qDebug() << i.previous();</pre>

<p>If you want to find all occurrences of a particular value, use <a href="qmutablelinkedlistiterator.html#findNext">findNext</a>() or <a href="qmutablelinkedlistiterator.html#findPrevious">findPrevious</a>() in a loop.</p>

<p>If you want to remove items as you iterate over the list, use <a href="qmutablelinkedlistiterator.html#remove">remove</a>(). If you want to modify the value of an item, use <a href="qmutablelinkedlistiterator.html#setValue">setValue</a>(). If you want to insert a new item in the list, use <a href="qmutablelinkedlistiterator.html#insert">insert</a>().</p>

<p>Example:</p>

<pre>  QMutableLinkedListIterator<int> i(list);

while (i.hasNext()) {

int val = i.next();

if (val < 0) {

i.setValue(-val);

} else if (val == 0) {

i.remove();

}

}</pre>

<pre> QMutableLinkedListIterator<int> i(list);

while (i.hasNext()) {

int val = i.next();

if (val < 0) {

i.setValue(-val);

} else if (val == 0) {

i.remove();

}

}</pre>

<p>The example traverses a list, replacing negative numbers with their absolute values, and eliminating zeroes.</p>

<p>Only one mutable iterator can be active on a given list at any time. Furthermore, no changes should be done directly to the list while the iterator is active (as opposed to through the iterator), since this could invalidate the iterator and lead to undefined behavior.</p>

<p>See also <a href="qlinkedlistiterator.html">QLinkedListIterator</a> and <a href="qlinkedlist-iterator.html">QLinkedList::iterator</a>.</p>

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<h3 class="fn"><a name="remove"></a>void QMutableLinkedListIterator::remove ()</h3>

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<p>Removes the last item that was jumped over using one of the traversal functions (<a href="qmutablelinkedlistiterator.html#next">next</a>(), <a href="qmutablelinkedlistiterator.html#previous">previous</a>(), <a href="qmutablelinkedlistiterator.html#findNext">findNext</a>(), <a href="qmutablelinkedlistiterator.html#findPrevious">findPrevious</a>()).</p>

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<p>Example:</p>

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<pre>  QMutableLinkedListIterator<int> i(list);

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while (i.hasNext()) {

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int val = i.next();

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if (val < -32768 || val > 32767)

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i.remove();

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}</pre>

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<pre> QMutableLinkedListIterator<int> i(list);

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while (i.hasNext()) {

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int val = i.next();

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if (val < -32768 || val > 32767)

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i.remove();

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}</pre>

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<p>See also <a href="qmutablelinkedlistiterator.html#insert">insert</a>() and <a href="qmutablelinkedlistiterator.html#setValue">setValue</a>().</p>

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<h3 class="fn"><a name="setValue"></a>void QMutableLinkedListIterator::setValue ( const T & <i>value</i> ) const</h3>

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<p>Replaces the value of the last item that was jumped over using one of the traversal functions with <i>value</i>.</p>

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<p>The traversal functions are <a href="qmutablelinkedlistiterator.html#next">next</a>(), <a href="qmutablelinkedlistiterator.html#previous">previous</a>(), <a href="qmutablelinkedlistiterator.html#findNext">findNext</a>(), and <a href="qmutablelinkedlistiterator.html#findPrevious">findPrevious</a>().</p>

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<p>Example:</p>

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<pre>  QMutableLinkedListIterator<double> i(list);

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while (i.hasNext()) {

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double val = i.next();

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i.setValue(sqrt(val));

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}</pre>

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<pre> QMutableLinkedListIterator<double> i(list);

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while (i.hasNext()) {

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double val = i.next();

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i.setValue(sqrt(val));

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}</pre>

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<p>See also <a href="qmutablelinkedlistiterator.html#value">value</a>(), <a href="qmutablelinkedlistiterator.html#remove">remove</a>(), and <a href="qmutablelinkedlistiterator.html#insert">insert</a>().</p>

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<h3 class="fn"><a name="toBack"></a>void QMutableLinkedListIterator::toBack ()</h3>

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<p>Moves the iterator to the back of the container (after the last item).</p>

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