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diff --git a/doc/html/qptrdict.html b/doc/html/qptrdict.html new file mode 100644 index 0000000..62d0026 --- /dev/null +++ b/doc/html/qptrdict.html @@ -0,0 +1,316 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> +<!-- /home/espenr/tmp/qt-3.3.8-espenr-2499/qt-x11-free-3.3.8/doc/qptrdict.doc:41 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>QPtrDict Class</title> +<style type="text/css"><!-- +fn { margin-left: 1cm; text-indent: -1cm; } +a:link { color: #004faf; text-decoration: none } +a:visited { color: #672967; text-decoration: none } +body { background: #ffffff; color: black; } +--></style> +</head> +<body> + +<table border="0" cellpadding="0" cellspacing="0" width="100%"> +<tr bgcolor="#E5E5E5"> +<td valign=center> + <a href="index.html"> +<font color="#004faf">Home</font></a> + | <a href="classes.html"> +<font color="#004faf">All Classes</font></a> + | <a href="mainclasses.html"> +<font color="#004faf">Main Classes</font></a> + | <a href="annotated.html"> +<font color="#004faf">Annotated</font></a> + | <a href="groups.html"> +<font color="#004faf">Grouped Classes</font></a> + | <a href="functions.html"> +<font color="#004faf">Functions</font></a> +</td> +<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>QPtrDict Class Reference</h1> + +<p>The QPtrDict class is a template class that provides a dictionary based on void* keys. +<a href="#details">More...</a> +<p><tt>#include <<a href="qptrdict-h.html">qptrdict.h</a>></tt> +<p>Inherits <a href="qptrcollection.html">QPtrCollection</a>. +<p><a href="qptrdict-members.html">List of all member functions.</a> +<h2>Public Members</h2> +<ul> +<li class=fn><a href="#QPtrDict"><b>QPtrDict</b></a> ( int size = 17 )</li> +<li class=fn><a href="#QPtrDict-2"><b>QPtrDict</b></a> ( const QPtrDict<type> & dict )</li> +<li class=fn><a href="#~QPtrDict"><b>~QPtrDict</b></a> ()</li> +<li class=fn>QPtrDict<type> & <a href="#operator-eq"><b>operator=</b></a> ( const QPtrDict<type> & dict )</li> +<li class=fn>virtual uint <a href="#count"><b>count</b></a> () const</li> +<li class=fn>uint <a href="#size"><b>size</b></a> () const</li> +<li class=fn>bool <a href="#isEmpty"><b>isEmpty</b></a> () const</li> +<li class=fn>void <a href="#insert"><b>insert</b></a> ( void * key, const type * item )</li> +<li class=fn>void <a href="#replace"><b>replace</b></a> ( void * key, const type * item )</li> +<li class=fn>bool <a href="#remove"><b>remove</b></a> ( void * key )</li> +<li class=fn>type * <a href="#take"><b>take</b></a> ( void * key )</li> +<li class=fn>type * <a href="#find"><b>find</b></a> ( void * key ) const</li> +<li class=fn>type * <a href="#operator[]"><b>operator[]</b></a> ( void * key ) const</li> +<li class=fn>virtual void <a href="#clear"><b>clear</b></a> ()</li> +<li class=fn>void <a href="#resize"><b>resize</b></a> ( uint newsize )</li> +<li class=fn>void <a href="#statistics"><b>statistics</b></a> () const</li> +</ul> +<h2>Important Inherited 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> +</ul> +<h2>Protected Members</h2> +<ul> +<li class=fn>virtual QDataStream & <a href="#read"><b>read</b></a> ( QDataStream & s, QPtrCollection::Item & item )</li> +<li class=fn>virtual QDataStream & <a href="#write"><b>write</b></a> ( QDataStream & s, QPtrCollection::Item ) const</li> +</ul> +<hr><a name="details"></a><h2>Detailed Description</h2> + + +The QPtrDict class is a template class that provides a dictionary based on void* keys. +<p> + +<p> +<p> QPtrDict is implemented as a template class. Define a template +instance QPtrDict<X> to create a dictionary that operates on +pointers to X (X*). +<p> A dictionary is a collection of key-value pairs. The key is a +void* used for insertion, removal and lookup. The value is a +pointer. Dictionaries provide very fast insertion and lookup. +<p> Example: +<pre> + QPtrDict<char> fields; // void* keys, char* values + + <a href="qlineedit.html">QLineEdit</a> *le1 = new <a href="qlineedit.html">QLineEdit</a>( this ); + le1-><a href="qlineedit.html#setText">setText</a>( "Simpson" ); + <a href="qlineedit.html">QLineEdit</a> *le2 = new <a href="qlineedit.html">QLineEdit</a>( this ); + le2-><a href="qlineedit.html#setText">setText</a>( "Homer" ); + <a href="qlineedit.html">QLineEdit</a> *le3 = new <a href="qlineedit.html">QLineEdit</a>( this ); + le3-><a href="qlineedit.html#setText">setText</a>( "45" ); + + fields.<a href="#insert">insert</a>( le1, "Surname" ); + fields.<a href="#insert">insert</a>( le2, "Forename" ); + fields.<a href="#insert">insert</a>( le3, "Age" ); + + <a href="qptrdictiterator.html">QPtrDictIterator</a><char> it( fields ); + for( ; it.<a href="qptrdictiterator.html#current">current</a>(); ++it ) + cout << it.<a href="qptrdictiterator.html#current">current</a>() << endl; + cout << endl; + + if ( fields[le1] ) // Prints "Surname: Simpson" + cout << fields[le1] << ": " << le1-><a href="qlineedit.html#text">text</a>() << endl; + if ( fields[le2] ) // Prints "Forename: Homer" + cout << fields[le2] << ": " << le2-><a href="qlineedit.html#text">text</a>() << endl; + + fields.<a href="#remove">remove</a>( le1 ); // Removes le1 from the dictionary + cout << le1-><a href="qlineedit.html#text">text</a>() << endl; // Prints "Simpson" + </pre> + +In this example we use a dictionary to add an extra property (a +char*) to the line edits we're using. +<p> See <a href="qdict.html">QDict</a> for full details, including the choice of dictionary +size, and how deletions are handled. +<p> <p>See also <a href="qptrdictiterator.html">QPtrDictIterator</a>, <a href="qdict.html">QDict</a>, <a href="qasciidict.html">QAsciiDict</a>, <a href="qintdict.html">QIntDict</a>, <a href="collection.html">Collection Classes</a>, <a href="collection.html">Collection Classes</a>, and <a href="tools.html">Non-GUI Classes</a>. + +<hr><h2>Member Function Documentation</h2> +<h3 class=fn><a name="QPtrDict"></a>QPtrDict::QPtrDict ( int size = 17 ) +</h3> + +<p> Constructs a dictionary using an internal hash array with the size +<em>size</em>. +<p> Setting <em>size</em> to a suitably large <a href="primes.html#prime">prime</a> number (equal to or +greater than the expected number of entries) makes the hash +distribution better and improves lookup performance. + +<h3 class=fn><a name="QPtrDict-2"></a>QPtrDict::QPtrDict ( const <a href="qptrdict.html">QPtrDict</a><type> & dict ) +</h3> + +<p> Constructs a copy of <em>dict</em>. +<p> Each item in <em>dict</em> is inserted into this dictionary. Only the +pointers are copied (shallow copy). + +<h3 class=fn><a name="~QPtrDict"></a>QPtrDict::~QPtrDict () +</h3> + +<p> Removes all items from the dictionary and destroys it. +<p> All iterators that access this dictionary will be reset. +<p> <p>See also <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>(). + +<h3 class=fn>bool <a name="autoDelete"></a>QPtrCollection::autoDelete () const +</h3> + +<p> Returns the setting of the auto-delete option. The default is FALSE. +<p> <p>See also <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>(). + +<h3 class=fn>void <a name="clear"></a>QPtrDict::clear ()<tt> [virtual]</tt> +</h3> + +<p> Removes all items from the dictionary. +<p> The removed items are deleted if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled. +<p> All dictionary iterators that access this dictionary will be +reset. +<p> <p>See also <a href="#remove">remove</a>(), <a href="#take">take</a>(), and <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>(). + +<p>Reimplemented from <a href="qptrcollection.html#clear">QPtrCollection</a>. +<h3 class=fn>uint <a name="count"></a>QPtrDict::count () const<tt> [virtual]</tt> +</h3> + +<p> Returns the number of items in the dictionary. +<p> <p>See also <a href="#isEmpty">isEmpty</a>(). + +<p>Reimplemented from <a href="qptrcollection.html#count">QPtrCollection</a>. +<h3 class=fn>type * <a name="find"></a>QPtrDict::find ( void * key ) const +</h3> + +<p> Returns the item associated with <em>key</em>, or 0 if the key does not +exist in the dictionary. +<p> If there are two or more items with equal keys, then the most +recently inserted item will be found. +<p> Equivalent to operator[]. +<p> <p>See also <a href="#operator[]">operator[]</a>(). + +<h3 class=fn>void <a name="insert"></a>QPtrDict::insert ( void * key, const type * item ) +</h3> + +<p> Inserts the <em>key</em> with the <em>item</em> into the dictionary. +<p> Multiple items can have the same key, in which case only the last +item will be accessible using <a href="#operator[]">operator[]</a>(). +<p> <em>item</em> may not be 0. +<p> <p>See also <a href="#replace">replace</a>(). + +<h3 class=fn>bool <a name="isEmpty"></a>QPtrDict::isEmpty () const +</h3> + +<p> Returns TRUE if the dictionary is empty; otherwise returns FALSE. +<p> <p>See also <a href="#count">count</a>(). + +<h3 class=fn><a href="qptrdict.html">QPtrDict</a><type> & <a name="operator-eq"></a>QPtrDict::operator= ( const <a href="qptrdict.html">QPtrDict</a><type> & dict ) +</h3> + +<p> Assigns <em>dict</em> to this dictionary and returns a reference to this +dictionary. +<p> This dictionary is first cleared and then each item in <em>dict</em> is +inserted into the dictionary. Only the pointers are copied +(shallow copy), unless <a href="qptrcollection.html#newItem">newItem</a>() has been reimplemented. + +<h3 class=fn>type * <a name="operator[]"></a>QPtrDict::operator[] ( void * key ) const +</h3> + +<p> Returns the item associated with <em>key</em>, or 0 if the key does not +exist in the dictionary. +<p> If there are two or more items with equal keys, then the most +recently inserted item will be found. +<p> Equivalent to the <a href="#find">find</a>() function. +<p> <p>See also <a href="#find">find</a>(). + +<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="read"></a>QPtrDict::read ( <a href="qdatastream.html">QDataStream</a> & s, <a href="qptrcollection.html#Item">QPtrCollection::Item</a> & item )<tt> [virtual protected]</tt> +</h3> + +<p> Reads a dictionary item from the stream <em>s</em> and returns a +reference to the stream. +<p> The default implementation sets <em>item</em> to 0. +<p> <p>See also <a href="#write">write</a>(). + +<h3 class=fn>bool <a name="remove"></a>QPtrDict::remove ( void * key ) +</h3> + +<p> Removes the item associated with <em>key</em> from the dictionary. +Returns TRUE if successful, i.e. if <em>key</em> is in the dictionary; +otherwise returns FALSE. +<p> If there are two or more items with equal keys, then the most +recently inserted item will be removed. +<p> The removed item is deleted if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled. +<p> All dictionary iterators that refer to the removed item will be +set to point to the next item in the dictionary traversal order. +<p> <p>See also <a href="#take">take</a>(), <a href="#clear">clear</a>(), and <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>(). + +<h3 class=fn>void <a name="replace"></a>QPtrDict::replace ( void * key, const type * item ) +</h3> + +<p> If the dictionary has key <em>key</em>, this key's item is replaced with +<em>item</em>. If the dictionary doesn't contain key <em>key</em>, <em>item</em> is +inserted into the dictionary using key <em>key</em>. +<p> <em>item</em> may not be 0. +<p> Equivalent to +<pre> + QPtrDict<ItemType> dict; + ... + if ( dict.<a href="#find">find</a>( key ) ) + dict.<a href="#remove">remove</a>( key ); + dict.<a href="#insert">insert</a>( key, item ); + </pre> + +<p> If there are two or more items with equal keys, then the most +recently inserted item will be replaced. +<p> <p>See also <a href="#insert">insert</a>(). + +<h3 class=fn>void <a name="resize"></a>QPtrDict::resize ( uint newsize ) +</h3> + +<p> Changes the size of the hash table to <em>newsize</em>. The contents of +the dictionary are preserved, but all iterators on the dictionary +become invalid. + +<h3 class=fn>void <a name="setAutoDelete"></a>QPtrCollection::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 <a href="#remove">remove</a>() +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="qptrcollection.html#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>. +<h3 class=fn>uint <a name="size"></a>QPtrDict::size () const +</h3> + +<p> Returns the size of the internal hash table (as specified in the +constructor). +<p> <p>See also <a href="#count">count</a>(). + +<h3 class=fn>void <a name="statistics"></a>QPtrDict::statistics () const +</h3> + +<p> Debugging-only function that prints out the dictionary +distribution using <a href="qapplication.html#qDebug">qDebug</a>(). + +<h3 class=fn>type * <a name="take"></a>QPtrDict::take ( void * key ) +</h3> + +<p> Takes the item associated with <em>key</em> out of the dictionary +without deleting it (even if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled). +<p> If there are two or more items with equal keys, then the most +recently inserted item will be removed. +<p> Returns a pointer to the item taken out, or 0 if the key does not +exist in the dictionary. +<p> All dictionary iterators that refer to the taken item will be set +to point to the next item in the dictionary traversal order. +<p> <p>See also <a href="#remove">remove</a>(), <a href="#clear">clear</a>(), and <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>(). + +<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="write"></a>QPtrDict::write ( <a href="qdatastream.html">QDataStream</a> & s, <a href="qptrcollection.html#Item">QPtrCollection::Item</a> ) const<tt> [virtual protected]</tt> +</h3> + +<p> Writes a dictionary item to the stream <em>s</em> and returns a +reference to the stream. +<p> <p>See also <a href="#read">read</a>(). + +<!-- eof --> +<hr><p> +This file is part of the <a href="index.html">Qt toolkit</a>. +Copyright © 1995-2007 +<a href="http://www.trolltech.com/">Trolltech</a>. 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