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The QPtrListIterator class provides an iterator for QPtrList collections. More...
#include <qptrlist.h>
Inherited by QStrListIterator.
Define a template instance QPtrListIterator<X> to create a list iterator that operates on QPtrList<X> (list of X*).
The following example is similar to the example in the QPtrList class documentation, but it uses QPtrListIterator. The class Employee is defined there.
QPtrList<Employee> list; list.append( new Employee("John", "Doe", 50000) ); list.append( new Employee("Jane", "Williams", 80000) ); list.append( new Employee("Tom", "Jones", 60000) ); QPtrListIterator<Employee> it( list ); Employee *employee; while ( (employee = it.current()) != 0 ) { ++it; cout << employee->surname().latin1() << ", " << employee->forename().latin1() << " earns " << employee->salary() << endl; }
The output is
Doe, John earns 50000 Williams, Jane earns 80000 Jones, Tom earns 60000
Using a list iterator is a more robust way of traversing the list than using the QPtrList member functions first(), next(), current(), etc., as many iterators can traverse the same list independently.
An iterator has its own current list item and can get the next and previous list items. It doesn't modifies the list in any way.
When an item is removed from the list, all iterator that points to that item are updated to point to QPtrList::currentItem() instead to avoid dangling references.
See also QPtrList, Collection Classes and Non-GUI Classes.
See also toFirst() and atLast().
See also toLast() and atFirst().
See also isEmpty().
Example: customlayout/card.cpp.
Examples: customlayout/card.cpp and customlayout/flow.cpp.
See also count().
If the current iterator item was the last item in the list or if it was null, null is returned.
If the current iterator item was the last item in the list or if it was null, null is returned.
If that item is beyond the last item or if the dictionary is empty, it sets the current item to null and returns null
If the current iterator item was the first item in the list or if it was null, null is returned.
See also toLast() and atFirst().
See also toFirst() and atLast().
This file is part of the Qt toolkit, copyright © 1995-2001 Trolltech, all rights reserved.
Copyright © 2001 Trolltech | Trademarks | Qt version 3.0.0-beta4
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