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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>TQPtrCollection Class Reference</h1>
<p>The TQPtrCollection class is the base class of most pointer-based TQt collections.
<a href="#details">More...</a>
<p>All the functions in this class are <a href="threads.html#reentrant">reentrant</a> when TQt is built with thread support.</p>
<p><tt>#include <<a href="qptrcollection-h.html">ntqptrcollection.h</a>></tt>
<p>Inherited by <a href="ntqasciicache.html">TQAsciiCache</a>, <a href="ntqasciidict.html">TQAsciiDict</a>, <a href="ntqcache.html">TQCache</a>, <a href="ntqdict.html">TQDict</a>, <a href="ntqintcache.html">TQIntCache</a>, <a href="ntqintdict.html">TQIntDict</a>, <a href="ntqptrlist.html">TQPtrList</a>, <a href="ntqptrdict.html">TQPtrDict</a>, and <a href="ntqptrvector.html">TQPtrVector</a>.
<p><a href="qptrcollection-members.html">List of all member functions.</a>
<h2>Public Members</h2>
<ul>
<li class=fn>bool <a href="#autoDelete"><b>autoDelete</b></a> () const</li>
<li class=fn>void <a href="#setAutoDelete"><b>setAutoDelete</b></a> ( bool enable )</li>
<li class=fn>virtual uint <a href="#count"><b>count</b></a> () const = 0</li>
<li class=fn>virtual void <a href="#clear"><b>clear</b></a> () = 0</li>
<li class=fn>typedef void * <a href="#Item"><b>Item</b></a></li>
</ul>
<h2>Protected Members</h2>
<ul>
<li class=fn><a href="#TQPtrCollection"><b>TQPtrCollection</b></a> ()</li>
<li class=fn><a href="#TQPtrCollection-2"><b>TQPtrCollection</b></a> ( const TQPtrCollection & source )</li>
<li class=fn>virtual <a href="#~TQPtrCollection"><b>~TQPtrCollection</b></a> ()</li>
<li class=fn>virtual Item <a href="#newItem"><b>newItem</b></a> ( Item d )</li>
<li class=fn>virtual void <a href="#deleteItem"><b>deleteItem</b></a> ( Item d ) = 0</li>
</ul>
<hr><a name="details"></a><h2>Detailed Description</h2>
The TQPtrCollection class is the base class of most pointer-based TQt collections.
<p>
<p> The TQPtrCollection class is an abstract base class for the TQt
<a href="collection.html">collection classes</a> <a href="ntqdict.html">TQDict</a>, <a href="ntqptrlist.html">TQPtrList</a>,
etc. TQt also includes value based collections, e.g. <a href="ntqvaluelist.html">TQValueList</a>,
<a href="ntqmap.html">TQMap</a>, etc.
<p> A TQPtrCollection only knows about the number of objects in the
collection and the deletion strategy (see <a href="#setAutoDelete">setAutoDelete</a>()).
<p> A collection is implemented using the <a href="#Item">Item</a> (generic collection
item) type, which is a <tt>void*</tt>. The template classes that create
the real collections cast the <a href="#Item">Item</a> to the required type.
<p>See also <a href="collection.html">Collection Classes</a> and <a href="tools.html">Non-GUI Classes</a>.
<hr><h2>Member Type Documentation</h2>
<h3 class=fn><a name="Item"></a>TQPtrCollection::Item</h3>
<p> This type is the generic "item" in a TQPtrCollection.
<hr><h2>Member Function Documentation</h2>
<h3 class=fn><a name="TQPtrCollection"></a>TQPtrCollection::TQPtrCollection ()<tt> [protected]</tt>
</h3>
<p> Constructs a collection. The constructor is protected because
TQPtrCollection is an abstract class.
<h3 class=fn><a name="TQPtrCollection-2"></a>TQPtrCollection::TQPtrCollection ( const <a href="ntqptrcollection.html">TQPtrCollection</a> & source )<tt> [protected]</tt>
</h3>
<p> Constructs a copy of <em>source</em> with <a href="#autoDelete">autoDelete</a>() set to FALSE. The
constructor is protected because TQPtrCollection is an abstract
class.
<p> Note that if <em>source</em> has autoDelete turned on, copying it will
risk memory leaks, reading freed memory, or both.
<h3 class=fn><a name="~TQPtrCollection"></a>TQPtrCollection::~TQPtrCollection ()<tt> [virtual protected]</tt>
</h3>
<p> Destroys the collection. The destructor is protected because
TQPtrCollection is an abstract class.
<h3 class=fn>bool <a name="autoDelete"></a>TQPtrCollection::autoDelete () const
</h3>
<p> Returns the setting of the auto-delete option. The default is FALSE.
<p> <p>See also <a href="#setAutoDelete">setAutoDelete</a>().
<h3 class=fn>void <a name="clear"></a>TQPtrCollection::clear ()<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>See also <a href="#setAutoDelete">setAutoDelete</a>().
<p>Reimplemented in <a href="ntqasciicache.html#clear">TQAsciiCache</a>, <a href="ntqasciidict.html#clear">TQAsciiDict</a>, <a href="ntqcache.html#clear">TQCache</a>, <a href="ntqdict.html#clear">TQDict</a>, <a href="ntqintcache.html#clear">TQIntCache</a>, <a href="ntqintdict.html#clear">TQIntDict</a>, <a href="ntqptrlist.html#clear">TQPtrList</a>, <a href="ntqptrdict.html#clear">TQPtrDict</a>, and <a href="ntqptrvector.html#clear">TQPtrVector</a>.
<h3 class=fn>uint <a name="count"></a>TQPtrCollection::count () const<tt> [pure virtual]</tt>
</h3>
<p> Returns the number of objects in the collection.
<p>Reimplemented in <a href="ntqasciicache.html#count">TQAsciiCache</a>, <a href="ntqasciidict.html#count">TQAsciiDict</a>, <a href="ntqcache.html#count">TQCache</a>, <a href="ntqdict.html#count">TQDict</a>, <a href="ntqintcache.html#count">TQIntCache</a>, <a href="ntqintdict.html#count">TQIntDict</a>, <a href="ntqptrlist.html#count">TQPtrList</a>, <a href="ntqptrdict.html#count">TQPtrDict</a>, and <a href="ntqptrvector.html#count">TQPtrVector</a>.
<h3 class=fn>void <a name="deleteItem"></a>TQPtrCollection::deleteItem ( <a href="ntqptrcollection.html#Item">Item</a> d )<tt> [pure virtual protected]</tt>
</h3>
<p> Reimplement this function if you want to be able to delete items.
<p> Deletes an item that is about to be removed from the collection.
<p> This function has to reimplemented in the collection template
classes, and should <em>only</em> delete item <em>d</em> if auto-delete has
been enabled.
<p> <b>Warning:</b> If you reimplement this function you must also
reimplement the destructor and call the virtual function <a href="#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
<a href="#deleteItem">deleteItem</a>() function will not be called when the container is
destroyed.
<p> <p>See also <a href="#newItem">newItem</a>() and <a href="#setAutoDelete">setAutoDelete</a>().
<h3 class=fn><a href="ntqptrcollection.html#Item">Item</a> <a name="newItem"></a>TQPtrCollection::newItem ( <a href="ntqptrcollection.html#Item">Item</a> d )<tt> [virtual protected]</tt>
</h3>
Virtual function that creates a copy of an object that is about to
be inserted into the collection.
<p> The default implementation returns the <em>d</em> pointer, i.e. no copy
is made.
<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>See also <a href="#deleteItem">deleteItem</a>().
<h3 class=fn>void <a name="setAutoDelete"></a>TQPtrCollection::setAutoDelete ( bool enable )
</h3>
<p> Sets the collection to auto-delete its contents if <em>enable</em> is
TRUE and to never delete them if <em>enable</em> is FALSE.
<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> 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> 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>See also <a href="#autoDelete">autoDelete</a>().
<p>Examples: <a href="grapher-nsplugin-example.html#x2769">grapher/grapher.cpp</a>, <a href="scribble-example.html#x924">scribble/scribble.cpp</a>, and <a href="bigtable-example.html#x1291">table/bigtable/main.cpp</a>.
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