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742 lines
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742 lines
41 KiB
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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>QPtrList Class Reference</h1>
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<p>The QPtrList class is a template class that provides a list.
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<a href="#details">More...</a>
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<p><tt>#include <<a href="qptrlist-h.html">qptrlist.h</a>></tt>
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<p>Inherits <a href="qptrcollection.html">QPtrCollection</a>.
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<p>Inherited by <a href="qobjectlist.html">QObjectList</a>, <a href="qsortedlist.html">QSortedList</a>, and <a href="qstrlist.html">QStrList</a>.
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<p><a href="qptrlist-members.html">List of all member functions.</a>
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<h2>Public Members</h2>
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<ul>
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<li class=fn><a href="#QPtrList"><b>QPtrList</b></a> ()</li>
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<li class=fn><a href="#QPtrList-2"><b>QPtrList</b></a> ( const QPtrList<type> & list )</li>
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<li class=fn><a href="#~QPtrList"><b>~QPtrList</b></a> ()</li>
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<li class=fn>QPtrList<type> & <a href="#operator-eq"><b>operator=</b></a> ( const QPtrList<type> & list )</li>
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<li class=fn>bool <a href="#operator-eq-eq"><b>operator==</b></a> ( const QPtrList<type> & list ) const</li>
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<li class=fn>bool <a href="#operator!-eq"><b>operator!=</b></a> ( const QPtrList<type> & list ) const</li>
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<li class=fn>virtual uint <a href="#count"><b>count</b></a> () const</li>
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<li class=fn>bool <a href="#isEmpty"><b>isEmpty</b></a> () const</li>
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<li class=fn>bool <a href="#insert"><b>insert</b></a> ( uint index, const type * item )</li>
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<li class=fn>void <a href="#inSort"><b>inSort</b></a> ( const type * item )</li>
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<li class=fn>void <a href="#prepend"><b>prepend</b></a> ( const type * item )</li>
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<li class=fn>void <a href="#append"><b>append</b></a> ( const type * item )</li>
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<li class=fn>bool <a href="#remove"><b>remove</b></a> ( uint index )</li>
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<li class=fn>bool <a href="#remove-2"><b>remove</b></a> ()</li>
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<li class=fn>bool <a href="#remove-3"><b>remove</b></a> ( const type * item )</li>
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<li class=fn>bool <a href="#removeRef"><b>removeRef</b></a> ( const type * item )</li>
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<li class=fn>void <a href="#removeNode"><b>removeNode</b></a> ( QLNode * node )</li>
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<li class=fn>bool <a href="#removeFirst"><b>removeFirst</b></a> ()</li>
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<li class=fn>bool <a href="#removeLast"><b>removeLast</b></a> ()</li>
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<li class=fn>type * <a href="#take"><b>take</b></a> ( uint index )</li>
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<li class=fn>type * <a href="#take-2"><b>take</b></a> ()</li>
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<li class=fn>type * <a href="#takeNode"><b>takeNode</b></a> ( QLNode * node )</li>
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<li class=fn>virtual void <a href="#clear"><b>clear</b></a> ()</li>
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<li class=fn>void <a href="#sort"><b>sort</b></a> ()</li>
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<li class=fn>int <a href="#find"><b>find</b></a> ( const type * item )</li>
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<li class=fn>int <a href="#findNext"><b>findNext</b></a> ( const type * item )</li>
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<li class=fn>int <a href="#findRef"><b>findRef</b></a> ( const type * item )</li>
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<li class=fn>int <a href="#findNextRef"><b>findNextRef</b></a> ( const type * item )</li>
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<li class=fn>uint <a href="#contains"><b>contains</b></a> ( const type * item ) const</li>
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<li class=fn>uint <a href="#containsRef"><b>containsRef</b></a> ( const type * item ) const</li>
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<li class=fn>bool <a href="#replace"><b>replace</b></a> ( uint index, const type * item )</li>
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<li class=fn>type * <a href="#at"><b>at</b></a> ( uint index )</li>
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<li class=fn>int <a href="#at-2"><b>at</b></a> () const</li>
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<li class=fn>type * <a href="#current"><b>current</b></a> () const</li>
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<li class=fn>QLNode * <a href="#currentNode"><b>currentNode</b></a> () const</li>
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<li class=fn>type * <a href="#getFirst"><b>getFirst</b></a> () const</li>
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<li class=fn>type * <a href="#getLast"><b>getLast</b></a> () const</li>
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<li class=fn>type * <a href="#first"><b>first</b></a> ()</li>
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<li class=fn>type * <a href="#last"><b>last</b></a> ()</li>
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<li class=fn>type * <a href="#next"><b>next</b></a> ()</li>
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<li class=fn>type * <a href="#prev"><b>prev</b></a> ()</li>
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<li class=fn>void <a href="#toVector"><b>toVector</b></a> ( QGVector * vec ) const</li>
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</ul>
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<h2>Important Inherited Members</h2>
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<ul>
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<li class=fn>bool <a href="#autoDelete"><b>autoDelete</b></a> () const</li>
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<li class=fn>void <a href="#setAutoDelete"><b>setAutoDelete</b></a> ( bool enable )</li>
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</ul>
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<h2>Protected Members</h2>
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<ul>
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<li class=fn>virtual int <a href="#compareItems"><b>compareItems</b></a> ( QPtrCollection::Item item1, QPtrCollection::Item item2 )</li>
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<li class=fn>virtual QDataStream & <a href="#read"><b>read</b></a> ( QDataStream & s, QPtrCollection::Item & item )</li>
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<li class=fn>virtual QDataStream & <a href="#write"><b>write</b></a> ( QDataStream & s, QPtrCollection::Item item ) const</li>
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</ul>
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<hr><a name="details"></a><h2>Detailed Description</h2>
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The QPtrList class is a template class that provides a list.
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<p>
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<p>
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<p> <a href="qvaluelist.html">QValueList</a> is an STL-compatible alternative to this class.
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<p> Define a template instance QPtrList<X> to create a list that
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operates on pointers to X (X*).
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<p> The list class is indexable and has a <a href="#at">current
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index</a> and a <a href="#current">current item</a>. The
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first item corresponds to index position 0. The current index is
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-1 if the current item is 0.
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<p> Items are inserted with <a href="#prepend">prepend</a>(), <a href="#insert">insert</a>() or <a href="#append">append</a>(). Items are
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removed with <a href="#remove">remove</a>(), <a href="#removeRef">removeRef</a>(), <a href="#removeFirst">removeFirst</a>() and
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<a href="#removeLast">removeLast</a>(). You can search for an item using <a href="#find">find</a>(), <a href="#findNext">findNext</a>(),
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<a href="#findRef">findRef</a>() or <a href="#findNextRef">findNextRef</a>(). The list can be sorted with <a href="#sort">sort</a>().
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You can count the number of occurrences of an item with <a href="#contains">contains</a>()
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or <a href="#containsRef">containsRef</a>(). You can get a pointer to the current item with
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<a href="#current">current</a>(), to an item at a particular index position in the list
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with <a href="#at">at</a>() or to the first or last item with <a href="#getFirst">getFirst</a>() and
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<a href="#getLast">getLast</a>(). You can also iterate over the list with <a href="#first">first</a>(),
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<a href="#last">last</a>(), <a href="#next">next</a>() and <a href="#prev">prev</a>() (which all update current()). The list's
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deletion property is set with <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>().
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<p> <a name="example"></a>
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Example:
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<pre>
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class Employee
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{
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public:
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Employee() : sn( 0 ) { }
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Employee( const <a href="qstring.html">QString</a>& forename, const <a href="qstring.html">QString</a>& surname, int salary )
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: fn( forename ), sn( surname ), sal( salary )
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{ }
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void setSalary( int salary ) { sal = salary; }
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<a href="qstring.html">QString</a> forename() const { return fn; }
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<a href="qstring.html">QString</a> surname() const { return sn; }
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int salary() const { return sal; }
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private:
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<a href="qstring.html">QString</a> fn;
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<a href="qstring.html">QString</a> sn;
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int sal;
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};
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QPtrList<Employee> list;
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list.<a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>( TRUE ); // the list owns the objects
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list.<a href="#append">append</a>( new Employee("John", "Doe", 50000) );
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list.<a href="#append">append</a>( new Employee("Jane", "Williams", 80000) );
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list.<a href="#append">append</a>( new Employee("Tom", "Jones", 60000) );
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Employee *employee;
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for ( employee = list.<a href="#first">first</a>(); employee; employee = list.<a href="#next">next</a>() )
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cout << employee->surname().latin1() << ", " <<
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employee->forename().latin1() << " earns " <<
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employee->salary() << endl;
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cout << endl;
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// very inefficient for big lists
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for ( uint i = 0; i < list.<a href="#count">count</a>(); ++i )
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if ( list.<a href="#at">at</a>(i) )
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cout << list.<a href="#at">at</a>( i )->surname().latin1() << endl;
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</pre>
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<p> The output is
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<pre>
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Doe, John earns 50000
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Williams, Jane earns 80000
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Jones, Tom earns 60000
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Doe
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Williams
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Jones
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</pre>
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<p> QPtrList has several member functions for traversing the list, but
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using a <a href="qptrlistiterator.html">QPtrListIterator</a> can be more practical. Multiple list
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iterators may traverse the same list, independently of each other
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and of the current list item.
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<p> In the example above we make the call <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>(TRUE).
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Enabling auto-deletion tells the list to delete items that are
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removed. The default is to not delete items when they are removed
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but this would cause a memory leak in the example because there
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are no other references to the list items.
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<p> When inserting an item into a list only the pointer is copied, not
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the item itself, i.e. a <a href="shclass.html#shallow-copy">shallow copy</a>. It is possible to make the
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list copy all of the item's data (deep copy) when an item is
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inserted. <a href="#insert">insert</a>(), <a href="#inSort">inSort</a>() and <a href="#append">append</a>() call the virtual
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function <a href="qptrcollection.html#newItem">QPtrCollection::newItem</a>() for the item to be inserted.
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Inherit a list and reimplement <a href="qptrcollection.html#newItem">newItem</a>() to have deep copies.
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<p> When removing an item from a list, the virtual function
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<a href="qptrcollection.html#deleteItem">QPtrCollection::deleteItem</a>() is called. QPtrList's default
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implementation is to delete the item if auto-deletion is enabled.
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<p> The virtual function <a href="#compareItems">compareItems</a>() can be reimplemented to
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compare two list items. This function is called from all list
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functions that need to compare list items, for instance
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<a href="#remove">remove</a>(const type*). If you only want to deal with pointers, there
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are functions that compare pointers instead, for instance
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<a href="#removeRef">removeRef</a>(const type*). These functions are somewhat faster than
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those that call compareItems().
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<p> List items are stored as <tt>void*</tt> in an internal QLNode, which
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also holds pointers to the next and previous list items. The
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functions <a href="#currentNode">currentNode</a>(), <a href="#removeNode">removeNode</a>(), and <a href="#takeNode">takeNode</a>() operate
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directly on the QLNode, but they should be used with care. The
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data component of the node is available through QLNode::getData().
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<p> The <a href="qstrlist.html">QStrList</a> class defined in <a href="qstrlist-h.html">qstrlist.h</a> is a list of <tt>char*</tt>.
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It reimplements <a href="qptrcollection.html#newItem">newItem</a>(), <a href="qptrcollection.html#deleteItem">deleteItem</a>() and <a href="#compareItems">compareItems</a>(). (But
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see <a href="qstringlist.html">QStringList</a> for a list of Unicode QStrings.)
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<p> <p>See also <a href="qptrlistiterator.html">QPtrListIterator</a>, <a href="collection.html">Collection Classes</a>, and <a href="tools.html">Non-GUI Classes</a>.
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<hr><h2>Member Function Documentation</h2>
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<h3 class=fn><a name="QPtrList"></a>QPtrList::QPtrList ()
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</h3>
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<p> Constructs an empty list.
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<h3 class=fn><a name="QPtrList-2"></a>QPtrList::QPtrList ( const <a href="qptrlist.html">QPtrList</a><type> & list )
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</h3>
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<p> Constructs a copy of <em>list</em>.
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<p> Each item in <em>list</em> is <a href="#append">appended</a> to this
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list. Only the pointers are copied (shallow copy).
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<h3 class=fn><a name="~QPtrList"></a>QPtrList::~QPtrList ()
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</h3>
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<p> Removes all items from the list and destroys the list.
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<p> All list iterators that access this list will be reset.
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<p> <p>See also <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>().
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<h3 class=fn>void <a name="append"></a>QPtrList::append ( const type * item )
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</h3>
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<p> Inserts the <em>item</em> at the end of the list.
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<p> The inserted item becomes the current list item. This is
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equivalent to <tt>insert( count(), item )</tt>.
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<p> <em>item</em> must not be 0.
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<p> <p>See also <a href="#insert">insert</a>(), <a href="#current">current</a>(), and <a href="#prepend">prepend</a>().
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<p>Examples: <a href="customlayout-example.html#x1500">customlayout/border.cpp</a>, <a href="customlayout-example.html#x1518">customlayout/card.cpp</a>, <a href="customlayout-example.html#x1477">customlayout/flow.cpp</a>, <a href="grapher-nsplugin-example.html#x2770">grapher/grapher.cpp</a>, <a href="listviews-example.html#x160">listviews/listviews.cpp</a>, <a href="listviews-example.html#x131">listviews/listviews.h</a>, and <a href="qwerty-example.html#x387">qwerty/qwerty.cpp</a>.
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<h3 class=fn>type * <a name="at"></a>QPtrList::at ( uint index )
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</h3>
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<p> Returns a pointer to the item at position <em>index</em> in the list, or
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0 if the index is out of range.
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<p> Sets the current list item to this item if <em>index</em> is valid. The
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valid range is <tt>0..(count() - 1)</tt> inclusive.
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<p> This function is very efficient. It starts scanning from the first
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item, last item, or current item, whichever is closest to <em>index</em>.
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<p> <p>See also <a href="#current">current</a>().
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<p>Examples: <a href="customlayout-example.html#x1501">customlayout/border.cpp</a>, <a href="customlayout-example.html#x1519">customlayout/card.cpp</a>, <a href="customlayout-example.html#x1478">customlayout/flow.cpp</a>, <a href="dirview-example.html#x1697">dirview/dirview.cpp</a>, <a href="mdi-example.html#x2053">mdi/application.cpp</a>, and <a href="qwerty-example.html#x388">qwerty/qwerty.cpp</a>.
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<h3 class=fn>int <a name="at-2"></a>QPtrList::at () const
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</h3>
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<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
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<p> Returns the index of the current list item. The returned value is
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-1 if the current item is 0.
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<p> <p>See also <a href="#current">current</a>().
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<h3 class=fn>bool <a name="autoDelete"></a>QPtrCollection::autoDelete () const
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</h3>
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<p> Returns the setting of the auto-delete option. The default is FALSE.
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<p> <p>See also <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>().
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<h3 class=fn>void <a name="clear"></a>QPtrList::clear ()<tt> [virtual]</tt>
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</h3>
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<p> Removes all items from the list.
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<p> The removed items are deleted if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled.
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<p> All list iterators that access this list will be reset.
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<p> <p>See also <a href="#remove">remove</a>(), <a href="#take">take</a>(), and <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>().
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<p>Reimplemented from <a href="qptrcollection.html#clear">QPtrCollection</a>.
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<h3 class=fn>int <a name="compareItems"></a>QPtrList::compareItems ( <a href="qptrcollection.html#Item">QPtrCollection::Item</a> item1, <a href="qptrcollection.html#Item">QPtrCollection::Item</a> item2 )<tt> [virtual protected]</tt>
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</h3>
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<p> This virtual function compares two list items.
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<p> Returns:
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<ul>
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<li> zero if <em>item1</em> == <em>item2</em>
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<li> nonzero if <em>item1</em> != <em>item2</em>
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</ul>
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<p> This function returns <em>int</em> rather than <em>bool</em> so that
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reimplementations can return three values and use it to sort by:
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<p> <ul>
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<li> 0 if <em>item1</em> == <em>item2</em>
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<li> > 0 (positive integer) if <em>item1</em> > <em>item2</em>
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<li> < 0 (negative integer) if <em>item1</em> < <em>item2</em>
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</ul>
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<p> <a href="#inSort">inSort</a>() requires that <a href="#compareItems">compareItems</a>() is implemented as described
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here.
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<p> This function should not modify the list because some const
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functions call compareItems().
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<p> The default implementation compares the pointers.
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<h3 class=fn>uint <a name="contains"></a>QPtrList::contains ( const type * item ) const
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</h3>
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<p> Returns the number of occurrences of <em>item</em> in the list.
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<p> The <a href="#compareItems">compareItems</a>() function is called when looking for the <em>item</em>
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in the list. If compareItems() is not reimplemented, it is more
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efficient to call <a href="#containsRef">containsRef</a>().
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<p> This function does not affect the current list item.
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<p> <p>See also <a href="#containsRef">containsRef</a>() and <a href="#compareItems">compareItems</a>().
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<h3 class=fn>uint <a name="containsRef"></a>QPtrList::containsRef ( const type * item ) const
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</h3>
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<p> Returns the number of occurrences of <em>item</em> in the list.
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<p> Calling this function is much faster than <a href="#contains">contains</a>() because
|
|
contains() compares <em>item</em> with each list item using
|
|
<a href="#compareItems">compareItems</a>(), whereas his function only compares the pointers.
|
|
<p> This function does not affect the current list item.
|
|
<p> <p>See also <a href="#contains">contains</a>().
|
|
|
|
<h3 class=fn>uint <a name="count"></a>QPtrList::count () const<tt> [virtual]</tt>
|
|
</h3>
|
|
|
|
<p> Returns the number of items in the list.
|
|
<p> <p>See also <a href="#isEmpty">isEmpty</a>().
|
|
|
|
<p>Examples: <a href="customlayout-example.html#x1502">customlayout/border.cpp</a>, <a href="customlayout-example.html#x1520">customlayout/card.cpp</a>, <a href="customlayout-example.html#x1479">customlayout/flow.cpp</a>, <a href="dirview-example.html#x1699">dirview/dirview.cpp</a>, <a href="grapher-nsplugin-example.html#x2771">grapher/grapher.cpp</a>, <a href="mdi-example.html#x2054">mdi/application.cpp</a>, and <a href="qwerty-example.html#x389">qwerty/qwerty.cpp</a>.
|
|
<p>Reimplemented from <a href="qptrcollection.html#count">QPtrCollection</a>.
|
|
<h3 class=fn>type * <a name="current"></a>QPtrList::current () const
|
|
</h3>
|
|
|
|
<p> Returns a pointer to the current list item. The current item may
|
|
be 0 (implies that the current index is -1).
|
|
<p> <p>See also <a href="#at">at</a>().
|
|
|
|
<h3 class=fn>QLNode * <a name="currentNode"></a>QPtrList::currentNode () const
|
|
</h3>
|
|
|
|
<p> Returns a pointer to the current list node.
|
|
<p> The node can be kept and removed later using <a href="#removeNode">removeNode</a>(). The
|
|
advantage is that the item can be removed directly without
|
|
searching the list.
|
|
<p> <b>Warning:</b> Do not call this function unless you are an expert.
|
|
<p> <p>See also <a href="#removeNode">removeNode</a>(), <a href="#takeNode">takeNode</a>(), and <a href="#current">current</a>().
|
|
|
|
<h3 class=fn>int <a name="find"></a>QPtrList::find ( const type * item )
|
|
</h3>
|
|
|
|
<p> Finds the first occurrence of <em>item</em> in the list.
|
|
<p> If the item is found, the list sets the current item to point to
|
|
the found item and returns the index of this item. If the item is
|
|
not found, the list sets the current item to 0, the current
|
|
index to -1, and returns -1.
|
|
<p> The <a href="#compareItems">compareItems</a>() function is called when searching for the item
|
|
in the list. If compareItems() is not reimplemented, it is more
|
|
efficient to call <a href="#findRef">findRef</a>().
|
|
<p> <p>See also <a href="#findNext">findNext</a>(), <a href="#findRef">findRef</a>(), <a href="#compareItems">compareItems</a>(), and <a href="#current">current</a>().
|
|
|
|
<h3 class=fn>int <a name="findNext"></a>QPtrList::findNext ( const type * item )
|
|
</h3>
|
|
|
|
<p> Finds the next occurrence of <em>item</em> in the list, starting from
|
|
the current list item.
|
|
<p> If the item is found, the list sets the current item to point to
|
|
the found item and returns the index of this item. If the item is
|
|
not found, the list sets the current item to 0, the current
|
|
index to -1, and returns -1.
|
|
<p> The <a href="#compareItems">compareItems</a>() function is called when searching for the item
|
|
in the list. If compareItems() is not reimplemented, it is more
|
|
efficient to call <a href="#findNextRef">findNextRef</a>().
|
|
<p> <p>See also <a href="#find">find</a>(), <a href="#findNextRef">findNextRef</a>(), <a href="#compareItems">compareItems</a>(), and <a href="#current">current</a>().
|
|
|
|
<h3 class=fn>int <a name="findNextRef"></a>QPtrList::findNextRef ( const type * item )
|
|
</h3>
|
|
|
|
<p> Finds the next occurrence of <em>item</em> in the list, starting from
|
|
the current list item.
|
|
<p> If the item is found, the list sets the current item to point to
|
|
the found item and returns the index of this item. If the item is
|
|
not found, the list sets the current item to 0, the current
|
|
index to -1, and returns -1.
|
|
<p> Calling this function is much faster than <a href="#findNext">findNext</a>() because
|
|
findNext() compares <em>item</em> with each list item using
|
|
<a href="#compareItems">compareItems</a>(), whereas this function only compares the pointers.
|
|
<p> <p>See also <a href="#findRef">findRef</a>(), <a href="#findNext">findNext</a>(), and <a href="#current">current</a>().
|
|
|
|
<h3 class=fn>int <a name="findRef"></a>QPtrList::findRef ( const type * item )
|
|
</h3>
|
|
|
|
<p> Finds the first occurrence of <em>item</em> in the list.
|
|
<p> If the item is found, the list sets the current item to point to
|
|
the found item and returns the index of this item. If the item is
|
|
not found, the list sets the current item to 0, the current
|
|
index to -1, and returns -1.
|
|
<p> Calling this function is much faster than <a href="#find">find</a>() because find()
|
|
compares <em>item</em> with each list item using <a href="#compareItems">compareItems</a>(), whereas
|
|
this function only compares the pointers.
|
|
<p> <p>See also <a href="#findNextRef">findNextRef</a>(), <a href="#find">find</a>(), and <a href="#current">current</a>().
|
|
|
|
<h3 class=fn>type * <a name="first"></a>QPtrList::first ()
|
|
</h3>
|
|
|
|
<p> Returns a pointer to the first item in the list and makes this the
|
|
current list item; returns 0 if the list is empty.
|
|
<p> <p>See also <a href="#getFirst">getFirst</a>(), <a href="#last">last</a>(), <a href="#next">next</a>(), <a href="#prev">prev</a>(), and <a href="#current">current</a>().
|
|
|
|
<p>Examples: <a href="grapher-nsplugin-example.html#x2772">grapher/grapher.cpp</a>, <a href="listviews-example.html#x132">listviews/listviews.h</a>, and <a href="showimg-example.html#x1343">showimg/showimg.cpp</a>.
|
|
<h3 class=fn>type * <a name="getFirst"></a>QPtrList::getFirst () const
|
|
</h3>
|
|
|
|
<p> Returns a pointer to the first item in the list, or 0 if the list
|
|
is empty.
|
|
<p> This function does not affect the current list item.
|
|
<p> <p>See also <a href="#first">first</a>() and <a href="#getLast">getLast</a>().
|
|
|
|
<h3 class=fn>type * <a name="getLast"></a>QPtrList::getLast () const
|
|
</h3>
|
|
|
|
<p> Returns a pointer to the last item in the list, or 0 if the list
|
|
is empty.
|
|
<p> This function does not affect the current list item.
|
|
<p> <p>See also <a href="#last">last</a>() and <a href="#getFirst">getFirst</a>().
|
|
|
|
<h3 class=fn>void <a name="inSort"></a>QPtrList::inSort ( const type * item )
|
|
</h3>
|
|
|
|
<p> Inserts the <em>item</em> at its sorted position in the list.
|
|
<p> The sort order depends on the virtual <a href="#compareItems">compareItems</a>() function. All
|
|
items must be inserted with <a href="#inSort">inSort</a>() to maintain the sorting
|
|
order.
|
|
<p> The inserted item becomes the current list item.
|
|
<p> <em>item</em> must not be 0.
|
|
<p> <b>Warning:</b> Using inSort() is slow. An alternative, especially if you
|
|
have lots of items, is to simply <a href="#append">append</a>() or <a href="#insert">insert</a>() them and
|
|
then use <a href="#sort">sort</a>(). inSort() takes up to O(n) compares. That means
|
|
inserting n items in your list will need O(n^2) compares whereas
|
|
sort() only needs O(n*log n) for the same task. So use inSort()
|
|
only if you already have a presorted list and want to insert just
|
|
a few additional items.
|
|
<p> <p>See also <a href="#insert">insert</a>(), <a href="#compareItems">compareItems</a>(), <a href="#current">current</a>(), and <a href="#sort">sort</a>().
|
|
|
|
<h3 class=fn>bool <a name="insert"></a>QPtrList::insert ( uint index, const type * item )
|
|
</h3>
|
|
|
|
<p> Inserts the <em>item</em> at position <em>index</em> in the list.
|
|
<p> Returns TRUE if successful, i.e. if <em>index</em> is in range;
|
|
otherwise returns FALSE. The valid range is 0 to <a href="#count">count</a>()
|
|
(inclusively). The item is appended if <em>index</em> == count().
|
|
<p> The inserted item becomes the current list item.
|
|
<p> <em>item</em> must not be 0.
|
|
<p> <p>See also <a href="#append">append</a>(), <a href="#current">current</a>(), and <a href="#replace">replace</a>().
|
|
|
|
<h3 class=fn>bool <a name="isEmpty"></a>QPtrList::isEmpty () const
|
|
</h3>
|
|
|
|
<p> Returns TRUE if the list is empty; otherwise returns FALSE.
|
|
<p> <p>See also <a href="#count">count</a>().
|
|
|
|
<h3 class=fn>type * <a name="last"></a>QPtrList::last ()
|
|
</h3>
|
|
|
|
<p> Returns a pointer to the last item in the list and makes this the
|
|
current list item; returns 0 if the list is empty.
|
|
<p> <p>See also <a href="#getLast">getLast</a>(), <a href="#first">first</a>(), <a href="#next">next</a>(), <a href="#prev">prev</a>(), and <a href="#current">current</a>().
|
|
|
|
<h3 class=fn>type * <a name="next"></a>QPtrList::next ()
|
|
</h3>
|
|
|
|
<p> Returns a pointer to the item succeeding the current item. Returns
|
|
0 if the current item is 0 or equal to the last item.
|
|
<p> Makes the succeeding item current. If the current item before this
|
|
function call was the last item, the current item will be set to
|
|
0. If the current item was 0, this function does nothing.
|
|
<p> <p>See also <a href="#first">first</a>(), <a href="#last">last</a>(), <a href="#prev">prev</a>(), and <a href="#current">current</a>().
|
|
|
|
<p>Examples: <a href="grapher-nsplugin-example.html#x2773">grapher/grapher.cpp</a>, <a href="listviews-example.html#x133">listviews/listviews.h</a>, and <a href="showimg-example.html#x1344">showimg/showimg.cpp</a>.
|
|
<h3 class=fn>bool <a name="operator!-eq"></a>QPtrList::operator!= ( const <a href="qptrlist.html">QPtrList</a><type> & list ) const
|
|
</h3>
|
|
|
|
<p> Compares this list with <em>list</em>. Returns TRUE if the lists contain
|
|
different data; otherwise returns FALSE.
|
|
|
|
<h3 class=fn><a href="qptrlist.html">QPtrList</a><type> & <a name="operator-eq"></a>QPtrList::operator= ( const <a href="qptrlist.html">QPtrList</a><type> & list )
|
|
</h3>
|
|
|
|
<p> Assigns <em>list</em> to this list and returns a reference to this list.
|
|
<p> This list is first cleared and then each item in <em>list</em> is <a href="#append">appended</a> to this list. Only the pointers are
|
|
copied (shallow copy) unless <a href="qptrcollection.html#newItem">newItem</a>() has been reimplemented.
|
|
|
|
<h3 class=fn>bool <a name="operator-eq-eq"></a>QPtrList::operator== ( const <a href="qptrlist.html">QPtrList</a><type> & list ) const
|
|
</h3>
|
|
|
|
<p> Compares this list with <em>list</em>. Returns TRUE if the lists contain
|
|
the same data; otherwise returns FALSE.
|
|
|
|
<h3 class=fn>void <a name="prepend"></a>QPtrList::prepend ( const type * item )
|
|
</h3>
|
|
|
|
<p> Inserts the <em>item</em> at the start of the list.
|
|
<p> The inserted item becomes the current list item. This is
|
|
equivalent to <tt>insert( 0, item )</tt>.
|
|
<p> <em>item</em> must not be 0.
|
|
<p> <p>See also <a href="#append">append</a>(), <a href="#insert">insert</a>(), and <a href="#current">current</a>().
|
|
|
|
<h3 class=fn>type * <a name="prev"></a>QPtrList::prev ()
|
|
</h3>
|
|
|
|
<p> Returns a pointer to the item preceding the current item. Returns
|
|
0 if the current item is 0 or equal to the first item.
|
|
<p> Makes the preceding item current. If the current item before this
|
|
function call was the first item, the current item will be set to
|
|
0. If the current item was 0, this function does nothing.
|
|
<p> <p>See also <a href="#first">first</a>(), <a href="#last">last</a>(), <a href="#next">next</a>(), and <a href="#current">current</a>().
|
|
|
|
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="read"></a>QPtrList::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 list 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>QPtrList::remove ( uint index )
|
|
</h3>
|
|
|
|
<p> Removes the item at position <em>index</em> in the list.
|
|
<p> Returns TRUE if successful, i.e. if <em>index</em> is in range;
|
|
otherwise returns FALSE. The valid range is <tt>0..(count() - 1)</tt>
|
|
inclusive.
|
|
<p> The removed item is deleted if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled.
|
|
<p> The item after the removed item becomes the new current list item
|
|
if the removed item is not the last item in the list. If the last
|
|
item is removed, the new last item becomes the current item.
|
|
<p> All list iterators that refer to the removed item will be set to
|
|
point to the new current item.
|
|
<p> <p>See also <a href="#take">take</a>(), <a href="#clear">clear</a>(), <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>(), <a href="#current">current</a>(), and <a href="#removeRef">removeRef</a>().
|
|
|
|
<h3 class=fn>bool <a name="remove-2"></a>QPtrList::remove ()
|
|
</h3>
|
|
|
|
<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
|
|
<p> Removes the current list item.
|
|
<p> Returns TRUE if successful, i.e. if the current item isn't 0;
|
|
otherwise returns FALSE.
|
|
<p> The removed item is deleted if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled.
|
|
<p> The item after the removed item becomes the new current list item
|
|
if the removed item is not the last item in the list. If the last
|
|
item is removed, the new last item becomes the current item. The
|
|
current item is set to 0 if the list becomes empty.
|
|
<p> All list iterators that refer to the removed item will be set to
|
|
point to the new current item.
|
|
<p> <p>See also <a href="#take">take</a>(), <a href="#clear">clear</a>(), <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>(), <a href="#current">current</a>(), and <a href="#removeRef">removeRef</a>().
|
|
|
|
<h3 class=fn>bool <a name="remove-3"></a>QPtrList::remove ( const type * item )
|
|
</h3>
|
|
|
|
<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
|
|
<p> Removes the first occurrence of <em>item</em> from the list.
|
|
<p> Returns TRUE if successful, i.e. if <em>item</em> is in the list;
|
|
otherwise returns FALSE.
|
|
<p> The removed item is deleted if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled.
|
|
<p> The <a href="#compareItems">compareItems</a>() function is called when searching for the item
|
|
in the list. If compareItems() is not reimplemented, it is more
|
|
efficient to call <a href="#removeRef">removeRef</a>().
|
|
<p> If <em>item</em> is NULL then the current item is removed from the list.
|
|
<p> The item after the removed item becomes the new current list item
|
|
if the removed item is not the last item in the list. If the last
|
|
item is removed, the new last item becomes the current item. The
|
|
current item is set to 0 if the list becomes empty.
|
|
<p> All list iterators that refer to the removed item will be set to
|
|
point to the new current item.
|
|
<p> <p>See also <a href="#removeRef">removeRef</a>(), <a href="#take">take</a>(), <a href="#clear">clear</a>(), <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>(), <a href="#compareItems">compareItems</a>(), and <a href="#current">current</a>().
|
|
|
|
<h3 class=fn>bool <a name="removeFirst"></a>QPtrList::removeFirst ()
|
|
</h3>
|
|
|
|
<p> Removes the first item from the list. Returns TRUE if successful,
|
|
i.e. if the list isn't empty; otherwise returns FALSE.
|
|
<p> The removed item is deleted if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled.
|
|
<p> The first item in the list becomes the new current list item. The
|
|
current item is set to 0 if the list becomes empty.
|
|
<p> All list iterators that refer to the removed item will be set to
|
|
point to the new current item.
|
|
<p> <p>See also <a href="#removeLast">removeLast</a>(), <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>(), <a href="#current">current</a>(), and <a href="#remove">remove</a>().
|
|
|
|
<h3 class=fn>bool <a name="removeLast"></a>QPtrList::removeLast ()
|
|
</h3>
|
|
|
|
<p> Removes the last item from the list. Returns TRUE if successful,
|
|
i.e. if the list isn't empty; otherwise returns FALSE.
|
|
<p> The removed item is deleted if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled.
|
|
<p> The last item in the list becomes the new current list item. The
|
|
current item is set to 0 if the list becomes empty.
|
|
<p> All list iterators that refer to the removed item will be set to
|
|
point to the new current item.
|
|
<p> <p>See also <a href="#removeFirst">removeFirst</a>(), <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>(), and <a href="#current">current</a>().
|
|
|
|
<h3 class=fn>void <a name="removeNode"></a>QPtrList::removeNode ( QLNode * node )
|
|
</h3>
|
|
|
|
<p> Removes the <em>node</em> from the list.
|
|
<p> This node must exist in the list, otherwise the program may crash.
|
|
<p> The removed item is deleted if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled.
|
|
<p> The first item in the list will become the new current list item.
|
|
The current item is set to 0 if the list becomes empty.
|
|
<p> All list iterators that refer to the removed item will be set to
|
|
point to the item succeeding this item or to the preceding item if
|
|
the removed item was the last item.
|
|
<p> <b>Warning:</b> Do not call this function unless you are an expert.
|
|
<p> <p>See also <a href="#takeNode">takeNode</a>(), <a href="#currentNode">currentNode</a>(), <a href="#remove">remove</a>(), and <a href="#removeRef">removeRef</a>().
|
|
|
|
<h3 class=fn>bool <a name="removeRef"></a>QPtrList::removeRef ( const type * item )
|
|
</h3>
|
|
|
|
<p> Removes the first occurrence of <em>item</em> from the list.
|
|
<p> Returns TRUE if successful, i.e. if <em>item</em> is in the list;
|
|
otherwise returns FALSE.
|
|
<p> The removed item is deleted if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled.
|
|
<p> Equivalent to:
|
|
<pre>
|
|
if ( list.findRef( item ) != -1 )
|
|
list.remove();
|
|
</pre>
|
|
|
|
<p> The item after the removed item becomes the new current list item
|
|
if the removed item is not the last item in the list. If the last
|
|
item is removed, the new last item becomes the current item. The
|
|
current item is set to 0 if the list becomes empty.
|
|
<p> All list iterators that refer to the removed item will be set to
|
|
point to the new current item.
|
|
<p> <p>See also <a href="#remove">remove</a>(), <a href="#clear">clear</a>(), <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>(), and <a href="#current">current</a>().
|
|
|
|
<h3 class=fn>bool <a name="replace"></a>QPtrList::replace ( uint index, const type * item )
|
|
</h3>
|
|
|
|
<p> Replaces the item at position <em>index</em> with the new <em>item</em>.
|
|
<p> Returns TRUE if successful, i.e. <em>index</em> is in the range 0 to
|
|
<a href="#count">count</a>()-1.
|
|
<p> <p>See also <a href="#append">append</a>(), <a href="#current">current</a>(), and <a href="#insert">insert</a>().
|
|
|
|
<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>void <a name="sort"></a>QPtrList::sort ()
|
|
</h3>
|
|
|
|
<p> Sorts the list by the result of the virtual <a href="#compareItems">compareItems</a>()
|
|
function.
|
|
<p> The heap sort algorithm is used for sorting. It sorts n items with
|
|
O(n*log n) comparisons. This is the asymptotic optimal solution of
|
|
the sorting problem.
|
|
<p> If the items in your list support <a href="qcstring.html#operator-lt-2">operator<</a>() and <a href="#operator-eq-eq">operator==</a>(),
|
|
you might be better off with QSortedList because it implements the
|
|
compareItems() function for you using these two operators.
|
|
<p> <p>See also <a href="#inSort">inSort</a>().
|
|
|
|
<h3 class=fn>type * <a name="take"></a>QPtrList::take ( uint index )
|
|
</h3>
|
|
|
|
<p> Takes the item at position <em>index</em> out of the list without
|
|
deleting it (even if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a>
|
|
is enabled).
|
|
<p> Returns a pointer to the item taken out of the list, or 0 if the
|
|
index is out of range. The valid range is <tt>0..(count() - 1)</tt>
|
|
inclusive.
|
|
<p> The item after the removed item becomes the new current list item
|
|
if the removed item is not the last item in the list. If the last
|
|
item is removed, the new last item becomes the current item. The
|
|
current item is set to 0 if the list becomes empty.
|
|
<p> All list iterators that refer to the taken item will be set to
|
|
point to the new current item.
|
|
<p> <p>See also <a href="#remove">remove</a>(), <a href="#clear">clear</a>(), and <a href="#current">current</a>().
|
|
|
|
<p>Examples: <a href="customlayout-example.html#x1503">customlayout/border.cpp</a>, <a href="customlayout-example.html#x1521">customlayout/card.cpp</a>, and <a href="customlayout-example.html#x1480">customlayout/flow.cpp</a>.
|
|
<h3 class=fn>type * <a name="take-2"></a>QPtrList::take ()
|
|
</h3>
|
|
|
|
<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
|
|
<p> Takes the current item out of the list without deleting it (even
|
|
if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled).
|
|
<p> Returns a pointer to the item taken out of the list, or 0 if
|
|
the current item is 0.
|
|
<p> The item after the removed item becomes the new current list item
|
|
if the removed item is not the last item in the list. If the last
|
|
item is removed, the new last item becomes the current item. The
|
|
current item is set to 0 if the list becomes empty.
|
|
<p> All list iterators that refer to the taken item will be set to
|
|
point to the new current item.
|
|
<p> <p>See also <a href="#remove">remove</a>(), <a href="#clear">clear</a>(), and <a href="#current">current</a>().
|
|
|
|
<h3 class=fn>type * <a name="takeNode"></a>QPtrList::takeNode ( QLNode * node )
|
|
</h3>
|
|
|
|
<p> Takes the <em>node</em> out of the list without deleting its item (even
|
|
if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled).
|
|
Returns a pointer to the item taken out of the list.
|
|
<p> This node must exist in the list, otherwise the program may crash.
|
|
<p> The first item in the list becomes the new current list item.
|
|
<p> All list iterators that refer to the taken item will be set to
|
|
point to the item succeeding this item or to the preceding item if
|
|
the taken item was the last item.
|
|
<p> <b>Warning:</b> Do not call this function unless you are an expert.
|
|
<p> <p>See also <a href="#removeNode">removeNode</a>() and <a href="#currentNode">currentNode</a>().
|
|
|
|
<h3 class=fn>void <a name="toVector"></a>QPtrList::toVector ( QGVector * vec ) const
|
|
</h3>
|
|
|
|
<p> Stores all list items in the vector <em>vec</em>.
|
|
<p> The vector must be of the same item type, otherwise the result
|
|
will be undefined.
|
|
|
|
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="write"></a>QPtrList::write ( <a href="qdatastream.html">QDataStream</a> & s, <a href="qptrcollection.html#Item">QPtrCollection::Item</a> item ) const<tt> [virtual protected]</tt>
|
|
</h3>
|
|
|
|
<p> Writes a list item, <em>item</em> to the stream <em>s</em> and returns a
|
|
reference to the stream.
|
|
<p> The default implementation does nothing.
|
|
<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>. All Rights Reserved.<p><address><hr><div align=center>
|
|
<table width=100% cellspacing=0 border=0><tr>
|
|
<td>Copyright © 2007
|
|
<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a>
|
|
<td align=right><div align=right>Qt 3.3.8</div>
|
|
</table></div></address></body>
|
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</html>
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