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<li class="level1"><a href="#public-types">Public Types</a></li>
<li class="level1"><a href="#public-functions">Public Functions</a></li>
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<h1 class="title">Q3PtrCollection Class Reference</h1>
<!-- $$$Q3PtrCollection-brief -->
<p>The Q3PtrCollection class is the base class of most pointer-based Qt collections. <a href="#details">More...</a></p>
<!-- @@@Q3PtrCollection -->
<pre class="cpp"> <span class="preprocessor">#include <Q3PtrCollection></span></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 <a href="porting4.html">Porting to Qt 4</a> for more information.</p>
<p><b>Inherited by: </b><a href="q3asciicache.html">Q3AsciiCache</a>, <a href="q3asciidict.html">Q3AsciiDict</a>, <a href="q3cache.html">Q3Cache</a>, <a href="q3dict.html">Q3Dict</a>, <a href="q3intcache.html">Q3IntCache</a>, <a href="q3intdict.html">Q3IntDict</a>, <a href="q3ptrdict.html">Q3PtrDict</a>, <a href="q3ptrlist.html">Q3PtrList</a>, <a href="q3ptrqueue.html">Q3PtrQueue</a>, <a href="q3ptrstack.html">Q3PtrStack</a>, and <a href="q3ptrvector.html">Q3PtrVector</a>.</p>
<p><b>Note:</b> All functions in this class are <a href="threads-reentrancy.html#reentrant">reentrant</a>.</p>
<ul>
<li><a href="q3ptrcollection-members.html">List of all members, including inherited members</a></li>
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<a name="public-types"></a>
<h2>Public Types</h2>
<table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> typedef </td><td class="memItemRight bottomAlign"><b><a href="q3ptrcollection.html#Item-typedef">Item</a></b></td></tr>
</table>
<a name="public-functions"></a>
<h2>Public Functions</h2>
<table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="q3ptrcollection.html#autoDelete">autoDelete</a></b> () const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual void </td><td class="memItemRight bottomAlign"><b><a href="q3ptrcollection.html#clear">clear</a></b> () = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual uint </td><td class="memItemRight bottomAlign"><b><a href="q3ptrcollection.html#count">count</a></b> () const = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="q3ptrcollection.html#setAutoDelete">setAutoDelete</a></b> ( bool <i>enable</i> )</td></tr>
</table>
<a name="protected-functions"></a>
<h2>Protected Functions</h2>
<table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="q3ptrcollection.html#Q3PtrCollection">Q3PtrCollection</a></b> ()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="q3ptrcollection.html#Q3PtrCollection-2">Q3PtrCollection</a></b> ( const Q3PtrCollection & <i>source</i> )</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual </td><td class="memItemRight bottomAlign"><b><a href="q3ptrcollection.html#dtor.Q3PtrCollection">~Q3PtrCollection</a></b> ()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual void </td><td class="memItemRight bottomAlign"><b><a href="q3ptrcollection.html#deleteItem">deleteItem</a></b> ( Item <i>d</i> ) = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual Item </td><td class="memItemRight bottomAlign"><b><a href="q3ptrcollection.html#newItem">newItem</a></b> ( Item <i>d</i> )</td></tr>
</table>
<a name="details"></a>
<!-- $$$Q3PtrCollection-description -->
<div class="descr">
<h2>Detailed Description</h2>
<p>The Q3PtrCollection class is the base class of most pointer-based Qt collections.</p>
<p>The Q3PtrCollection class is an abstract base class for the Qt collection classes QDict, <a href="q3ptrlist.html">Q3PtrList</a>, etc.</p>
<p>A Q3PtrCollection only knows about the number of objects in the collection and the deletion strategy (see <a href="q3ptrcollection.html#setAutoDelete">setAutoDelete</a>()).</p>
<p>A collection is implemented using the <tt>Item</tt> (generic collection item) type, which is a <tt>void*</tt>. The template classes that create the real collections cast the <tt>Item</tt> to the required type.</p>
</div>
<!-- @@@Q3PtrCollection -->
<div class="types">
<h2>Member Type Documentation</h2>
<!-- $$$Item -->
<h3 class="fn"><a name="Item-typedef"></a>typedef Q3PtrCollection::<span class="name">Item</span></h3>
<p>This type is the generic "item" in a <a href="q3ptrcollection.html" class="compat">Q3PtrCollection</a>.</p>
<!-- @@@Item -->
</div>
<div class="func">
<h2>Member Function Documentation</h2>
<!-- $$$Q3PtrCollection[overload1]$$$Q3PtrCollection -->
<h3 class="fn"><a name="Q3PtrCollection"></a>Q3PtrCollection::<span class="name">Q3PtrCollection</span> ()<tt> [protected]</tt></h3>
<p>Constructs a collection. The constructor is protected because <a href="q3ptrcollection.html" class="compat">Q3PtrCollection</a> is an abstract class.</p>
<!-- @@@Q3PtrCollection -->
<!-- $$$Q3PtrCollection$$$Q3PtrCollectionconstQ3PtrCollection& -->
<h3 class="fn"><a name="Q3PtrCollection-2"></a>Q3PtrCollection::<span class="name">Q3PtrCollection</span> ( const <span class="type">Q3PtrCollection</span> & <i>source</i> )<tt> [protected]</tt></h3>
<p>Constructs a copy of <i>source</i> with <a href="q3ptrcollection.html#autoDelete">autoDelete</a>() set to false. The constructor is protected because <a href="q3ptrcollection.html" class="compat">Q3PtrCollection</a> is an abstract class.</p>
<p>Note that if <i>source</i> has autoDelete turned on, copying it will risk memory leaks, reading freed memory, or both.</p>
<!-- @@@Q3PtrCollection -->
<!-- $$$~Q3PtrCollection[overload1]$$$~Q3PtrCollection -->
<h3 class="fn"><a name="dtor.Q3PtrCollection"></a>Q3PtrCollection::<span class="name">~Q3PtrCollection</span> ()<tt> [virtual protected]</tt></h3>
<p>Destroys the collection. The destructor is protected because <a href="q3ptrcollection.html" class="compat">Q3PtrCollection</a> is an abstract class.</p>
<!-- @@@~Q3PtrCollection -->
<!-- $$$autoDelete[overload1]$$$autoDelete -->
<h3 class="fn"><a name="autoDelete"></a><span class="type">bool</span> Q3PtrCollection::<span class="name">autoDelete</span> () const</h3>
<p>Returns the setting of the auto-delete option. The default is false.</p>
<p><b>See also </b><a href="q3ptrcollection.html#setAutoDelete">setAutoDelete</a>().</p>
<!-- @@@autoDelete -->
<!-- $$$clear[overload1]$$$clear -->
<h3 class="fn"><a name="clear"></a><span class="type">void</span> Q3PtrCollection::<span class="name">clear</span> ()<tt> [pure virtual]</tt></h3>
<p>Removes all objects from the collection. The objects will be deleted if auto-delete has been enabled.</p>
<p><b>See also </b><a href="q3ptrcollection.html#setAutoDelete">setAutoDelete</a>().</p>
<!-- @@@clear -->
<!-- $$$count[overload1]$$$count -->
<h3 class="fn"><a name="count"></a><span class="type"><a href="qtglobal.html#uint-typedef">uint</a></span> Q3PtrCollection::<span class="name">count</span> () const<tt> [pure virtual]</tt></h3>
<p>Returns the number of objects in the collection.</p>
<!-- @@@count -->
<!-- $$$deleteItem[overload1]$$$deleteItemItem -->
<h3 class="fn"><a name="deleteItem"></a><span class="type">void</span> Q3PtrCollection::<span class="name">deleteItem</span> ( <span class="type"><a href="q3ptrcollection.html#Item-typedef">Item</a></span> <i>d</i> )<tt> [pure virtual protected]</tt></h3>
<p>Reimplement this function if you want to be able to delete items.</p>
<p>Deletes an item that is about to be removed from the collection.</p>
<p>This function has to reimplemented in the collection template classes, and should <i>only</i> delete item <i>d</i> if auto-delete has been enabled.</p>
<p><b>Warning:</b> If you reimplement this function you must also reimplement the destructor and call the virtual function <a href="q3ptrcollection.html#clear">clear</a>() from your destructor. This is due to the way virtual functions and destructors work in C++: Virtual functions in derived classes cannot be called from a destructor. If you do not do this, your deleteItem() function will not be called when the container is destroyed.</p>
<p><b>See also </b><a href="q3ptrcollection.html#newItem">newItem</a>() and <a href="q3ptrcollection.html#setAutoDelete">setAutoDelete</a>().</p>
<!-- @@@deleteItem -->
<!-- $$$newItem[overload1]$$$newItemItem -->
<h3 class="fn"><a name="newItem"></a><span class="type"><a href="q3ptrcollection.html#Item-typedef">Item</a></span> Q3PtrCollection::<span class="name">newItem</span> ( <span class="type"><a href="q3ptrcollection.html#Item-typedef">Item</a></span> <i>d</i> )<tt> [virtual protected]</tt></h3>
<p>Virtual function that creates a copy of an object that is about to be inserted into the collection.</p>
<p>The default implementation returns the <i>d</i> pointer, i.e. no copy is made.</p>
<p>This function is seldom reimplemented in the collection template classes. It is not common practice to make a copy of something that is being inserted.</p>
<p><b>See also </b><a href="q3ptrcollection.html#deleteItem">deleteItem</a>().</p>
<!-- @@@newItem -->
<!-- $$$setAutoDelete[overload1]$$$setAutoDeletebool -->
<h3 class="fn"><a name="setAutoDelete"></a><span class="type">void</span> Q3PtrCollection::<span class="name">setAutoDelete</span> ( <span class="type">bool</span> <i>enable</i> )</h3>
<p>Sets the collection to auto-delete its contents if <i>enable</i> is true and to never delete them if <i>enable</i> is false.</p>
<p>If auto-deleting is turned on, all the items in a collection are deleted when the collection itself is deleted. This is convenient if the collection has the only pointer to the items.</p>
<p>The default setting is false, for safety. If you turn it on, be careful about copying the collection - you might find yourself with two collections deleting the same items.</p>
<p>Note that the auto-delete setting may also affect other functions in subclasses. For example, a subclass that has a remove() function will remove the item from its data structure, and if auto-delete is enabled, will also delete the item.</p>
<p><b>See also </b><a href="q3ptrcollection.html#autoDelete">autoDelete</a>().</p>
<!-- @@@setAutoDelete -->
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