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tqt3/doc/qptrlist.doc

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/****************************************************************************
**
** QPtrList and QPtrListIterator class documentation
**
** Copyright (C) 1992-2008 Trolltech ASA. All rights reserved.
**
** This file is part of the TQt GUI Toolkit.
**
** This file may be used under the terms of the GNU General
** Public License versions 2.0 or 3.0 as published by the Free
** Software Foundation and appearing in the files LICENSE.GPL2
** and LICENSE.GPL3 included in the packaging of this file.
** Alternatively you may (at your option) use any later version
** of the GNU General Public License if such license has been
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** and the KDE Free TQt Foundation.
**
** Please review the following information to ensure GNU General
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** If you are unsure which license is appropriate for your use, please
** review the following information:
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**
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** This file is provided "AS IS" with NO WARRANTY OF ANY KIND,
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**********************************************************************/
/*****************************************************************************
QPtrList documentation
*****************************************************************************/
/*!
\class QPtrList
\brief The QPtrList class is a template class that provides a list.
\ingroup collection
\ingroup tools
\important autoDelete setAutoDelete
QValueList is an STL-compatible alternative to this class.
Define a template instance QPtrList\<X\> to create a list that
operates on pointers to X (X*).
The list class is indexable and has a \link at() current
index\endlink and a \link current() current item\endlink. The
first item corresponds to index position 0. The current index is
-1 if the current item is 0.
Items are inserted with prepend(), insert() or append(). Items are
removed with remove(), removeRef(), removeFirst() and
removeLast(). You can search for an item using find(), findNext(),
findRef() or findNextRef(). The list can be sorted with sort().
You can count the number of occurrences of an item with contains()
or containsRef(). You can get a pointer to the current item with
current(), to an item at a particular index position in the list
with at() or to the first or last item with getFirst() and
getLast(). You can also iterate over the list with first(),
last(), next() and prev() (which all update current()). The list's
deletion property is set with setAutoDelete().
\target example
Example:
\code
class Employee
{
public:
Employee() : sn( 0 ) { }
Employee( const QString& forename, const QString& surname, int salary )
: fn( forename ), sn( surname ), sal( salary )
{ }
void setSalary( int salary ) { sal = salary; }
QString forename() const { return fn; }
QString surname() const { return sn; }
int salary() const { return sal; }
private:
QString fn;
QString sn;
int sal;
};
QPtrList<Employee> list;
list.setAutoDelete( TRUE ); // the list owns the objects
list.append( new Employee("John", "Doe", 50000) );
list.append( new Employee("Jane", "Williams", 80000) );
list.append( new Employee("Tom", "Jones", 60000) );
Employee *employee;
for ( employee = list.first(); employee; employee = list.next() )
cout << employee->surname().latin1() << ", " <<
employee->forename().latin1() << " earns " <<
employee->salary() << endl;
cout << endl;
// very inefficient for big lists
for ( uint i = 0; i < list.count(); ++i )
if ( list.at(i) )
cout << list.at( i )->surname().latin1() << endl;
\endcode
The output is
\code
Doe, John earns 50000
Williams, Jane earns 80000
Jones, Tom earns 60000
Doe
Williams
Jones
\endcode
QPtrList has several member functions for traversing the list, but
using a QPtrListIterator can be more practical. Multiple list
iterators may traverse the same list, independently of each other
and of the current list item.
In the example above we make the call setAutoDelete(TRUE).
Enabling auto-deletion tells the list to delete items that are
removed. The default is to not delete items when they are removed
but this would cause a memory leak in the example because there
are no other references to the list items.
When inserting an item into a list only the pointer is copied, not
the item itself, i.e. a shallow copy. It is possible to make the
list copy all of the item's data (deep copy) when an item is
inserted. insert(), inSort() and append() call the virtual
function QPtrCollection::newItem() for the item to be inserted.
Inherit a list and reimplement newItem() to have deep copies.
When removing an item from a list, the virtual function
QPtrCollection::deleteItem() is called. QPtrList's default
implementation is to delete the item if auto-deletion is enabled.
The virtual function compareItems() can be reimplemented to
compare two list items. This function is called from all list
functions that need to compare list items, for instance
remove(const type*). If you only want to deal with pointers, there
are functions that compare pointers instead, for instance
removeRef(const type*). These functions are somewhat faster than
those that call compareItems().
List items are stored as \c void* in an internal QLNode, which
also holds pointers to the next and previous list items. The
functions currentNode(), removeNode(), and takeNode() operate
directly on the QLNode, but they should be used with care. The
data component of the node is available through QLNode::getData().
The QStrList class defined in \l ntqstrlist.h is a list of \c char*.
It reimplements newItem(), deleteItem() and compareItems(). (But
see QStringList for a list of Unicode QStrings.)
\sa QPtrListIterator
*/
/*!
\fn QPtrList::QPtrList()
Constructs an empty list.
*/
/*!
\fn QPtrList::QPtrList( const QPtrList<type> &list )
Constructs a copy of \a list.
Each item in \a list is \link append() appended\endlink to this
list. Only the pointers are copied (shallow copy).
*/
/*!
\fn QPtrList::~QPtrList()
Removes all items from the list and destroys the list.
All list iterators that access this list will be reset.
\sa setAutoDelete()
*/
/*!
\fn QPtrList<type> &QPtrList::operator=(const QPtrList<type> &list)
Assigns \a list to this list and returns a reference to this list.
This list is first cleared and then each item in \a list is \link
append() appended\endlink to this list. Only the pointers are
copied (shallow copy) unless newItem() has been reimplemented.
*/
/*!
\fn bool QPtrList::operator==(const QPtrList<type> &list ) const
Compares this list with \a list. Returns TRUE if the lists contain
the same data; otherwise returns FALSE.
*/
/*!
\fn uint QPtrList::count() const
Returns the number of items in the list.
\sa isEmpty()
*/
/*!
\fn bool QPtrList::operator!=(const QPtrList<type> &list ) const
Compares this list with \a list. Returns TRUE if the lists contain
different data; otherwise returns FALSE.
*/
/*!
\fn void QPtrList::sort()
Sorts the list by the result of the virtual compareItems()
function.
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.
\sa inSort()
*/
/*!
\fn bool QPtrList::isEmpty() const
Returns TRUE if the list is empty; otherwise returns FALSE.
\sa count()
*/
/*!
\fn bool QPtrList::insert( uint index, const type *item )
Inserts the \a item at position \a index in the list.
Returns TRUE if successful, i.e. if \a index is in range;
otherwise returns FALSE. The valid range is 0 to count()
(inclusively). The item is appended if \a index == count().
The inserted item becomes the current list item.
\a item must not be 0.
\sa append(), current(), replace()
*/
/*!
\fn bool QPtrList::replace( uint index, const type *item )
Replaces the item at position \a index with the new \a item.
Returns TRUE if successful, i.e. \a index is in the range 0 to
count()-1.
\sa append(), current(), insert()
*/
/*!
\fn void QPtrList::inSort( const type *item )
Inserts the \a item at its sorted position in the list.
The sort order depends on the virtual compareItems() function. All
items must be inserted with inSort() to maintain the sorting
order.
The inserted item becomes the current list item.
\a item must not be 0.
\warning Using inSort() is slow. An alternative, especially if you
have lots of items, is to simply append() or insert() them and
then use sort(). 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.
\sa insert(), compareItems(), current(), sort()
*/
/*!
\fn void QPtrList::append( const type *item )
Inserts the \a item at the end of the list.
The inserted item becomes the current list item. This is
equivalent to \c{insert( count(), item )}.
\a item must not be 0.
\sa insert(), current(), prepend()
*/
/*!
\fn void QPtrList::prepend( const type *item )
Inserts the \a item at the start of the list.
The inserted item becomes the current list item. This is
equivalent to \c{insert( 0, item )}.
\a item must not be 0.
\sa append(), insert(), current()
*/
/*!
\fn bool QPtrList::remove( uint index )
Removes the item at position \a index in the list.
Returns TRUE if successful, i.e. if \a index is in range;
otherwise returns FALSE. The valid range is \c{0..(count() - 1)}
inclusive.
The removed item is deleted if \link setAutoDelete()
auto-deletion\endlink is enabled.
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.
All list iterators that refer to the removed item will be set to
point to the new current item.
\sa take(), clear(), setAutoDelete(), current() removeRef()
*/
/*!
\fn bool QPtrList::remove()
\overload
Removes the current list item.
Returns TRUE if successful, i.e. if the current item isn't 0;
otherwise returns FALSE.
The removed item is deleted if \link setAutoDelete()
auto-deletion\endlink is enabled.
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.
All list iterators that refer to the removed item will be set to
point to the new current item.
\sa take(), clear(), setAutoDelete(), current() removeRef()
*/
/*!
\fn bool QPtrList::remove( const type *item )
\overload
Removes the first occurrence of \a item from the list.
Returns TRUE if successful, i.e. if \a item is in the list;
otherwise returns FALSE.
The removed item is deleted if \link setAutoDelete()
auto-deletion\endlink is enabled.
The compareItems() function is called when searching for the item
in the list. If compareItems() is not reimplemented, it is more
efficient to call removeRef().
If \a item is NULL then the current item is removed from the list.
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.
All list iterators that refer to the removed item will be set to
point to the new current item.
\sa removeRef(), take(), clear(), setAutoDelete(), compareItems(),
current()
*/
/*!
\fn bool QPtrList::removeRef( const type *item )
Removes the first occurrence of \a item from the list.
Returns TRUE if successful, i.e. if \a item is in the list;
otherwise returns FALSE.
The removed item is deleted if \link setAutoDelete()
auto-deletion\endlink is enabled.
Equivalent to:
\code
if ( list.findRef( item ) != -1 )
list.remove();
\endcode
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.
All list iterators that refer to the removed item will be set to
point to the new current item.
\sa remove(), clear(), setAutoDelete(), current()
*/
/*!
\fn void QPtrList::removeNode( QLNode *node )
Removes the \a node from the list.
This node must exist in the list, otherwise the program may crash.
The removed item is deleted if \link setAutoDelete()
auto-deletion\endlink is enabled.
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.
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.
\warning Do not call this function unless you are an expert.
\sa takeNode(), currentNode() remove() removeRef()
*/
/*!
\fn bool QPtrList::removeFirst()
Removes the first item from the list. Returns TRUE if successful,
i.e. if the list isn't empty; otherwise returns FALSE.
The removed item is deleted if \link setAutoDelete()
auto-deletion\endlink is enabled.
The first item in the list becomes the new current list item. The
current item is set to 0 if the list becomes empty.
All list iterators that refer to the removed item will be set to
point to the new current item.
\sa removeLast(), setAutoDelete(), current() remove()
*/
/*!
\fn bool QPtrList::removeLast()
Removes the last item from the list. Returns TRUE if successful,
i.e. if the list isn't empty; otherwise returns FALSE.
The removed item is deleted if \link setAutoDelete()
auto-deletion\endlink is enabled.
The last item in the list becomes the new current list item. The
current item is set to 0 if the list becomes empty.
All list iterators that refer to the removed item will be set to
point to the new current item.
\sa removeFirst(), setAutoDelete(), current()
*/
/*!
\fn type *QPtrList::take( uint index )
Takes the item at position \a index out of the list without
deleting it (even if \link setAutoDelete() auto-deletion\endlink
is enabled).
Returns a pointer to the item taken out of the list, or 0 if the
index is out of range. The valid range is \c{0..(count() - 1)}
inclusive.
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.
All list iterators that refer to the taken item will be set to
point to the new current item.
\sa remove(), clear(), current()
*/
/*!
\fn type *QPtrList::take()
\overload
Takes the current item out of the list without deleting it (even
if \link setAutoDelete() auto-deletion\endlink is enabled).
Returns a pointer to the item taken out of the list, or 0 if
the current item is 0.
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.
All list iterators that refer to the taken item will be set to
point to the new current item.
\sa remove(), clear(), current()
*/
/*!
\fn type *QPtrList::takeNode( QLNode *node )
Takes the \a node out of the list without deleting its item (even
if \link setAutoDelete() auto-deletion\endlink is enabled).
Returns a pointer to the item taken out of the list.
This node must exist in the list, otherwise the program may crash.
The first item in the list becomes the new current list item.
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.
\warning Do not call this function unless you are an expert.
\sa removeNode(), currentNode()
*/
/*!
\fn void QPtrList::clear()
Removes all items from the list.
The removed items are deleted if \link setAutoDelete()
auto-deletion\endlink is enabled.
All list iterators that access this list will be reset.
\sa remove(), take(), setAutoDelete()
*/
/*!
\fn int QPtrList::find( const type *item )
Finds the first occurrence of \a item in the list.
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.
The compareItems() function is called when searching for the item
in the list. If compareItems() is not reimplemented, it is more
efficient to call findRef().
\sa findNext(), findRef(), compareItems(), current()
*/
/*!
\fn int QPtrList::findNext( const type *item )
Finds the next occurrence of \a item in the list, starting from
the current list item.
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.
The compareItems() function is called when searching for the item
in the list. If compareItems() is not reimplemented, it is more
efficient to call findNextRef().
\sa find(), findNextRef(), compareItems(), current()
*/
/*!
\fn int QPtrList::findRef( const type *item )
Finds the first occurrence of \a item in the list.
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.
Calling this function is much faster than find() because find()
compares \a item with each list item using compareItems(), whereas
this function only compares the pointers.
\sa findNextRef(), find(), current()
*/
/*!
\fn int QPtrList::findNextRef( const type *item )
Finds the next occurrence of \a item in the list, starting from
the current list item.
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.
Calling this function is much faster than findNext() because
findNext() compares \a item with each list item using
compareItems(), whereas this function only compares the pointers.
\sa findRef(), findNext(), current()
*/
/*!
\fn uint QPtrList::contains( const type *item ) const
Returns the number of occurrences of \a item in the list.
The compareItems() function is called when looking for the \a item
in the list. If compareItems() is not reimplemented, it is more
efficient to call containsRef().
This function does not affect the current list item.
\sa containsRef(), compareItems()
*/
/*!
\fn uint QPtrList::containsRef( const type *item ) const
Returns the number of occurrences of \a item in the list.
Calling this function is much faster than contains() because
contains() compares \a item with each list item using
compareItems(), whereas his function only compares the pointers.
This function does not affect the current list item.
\sa contains()
*/
/*!
\fn type *QPtrList::at( uint index )
Returns a pointer to the item at position \a index in the list, or
0 if the index is out of range.
Sets the current list item to this item if \a index is valid. The
valid range is \c{0..(count() - 1)} inclusive.
This function is very efficient. It starts scanning from the first
item, last item, or current item, whichever is closest to \a
index.
\sa current()
*/
/*!
\fn int QPtrList::at() const
\overload
Returns the index of the current list item. The returned value is
-1 if the current item is 0.
\sa current()
*/
/*!
\fn type *QPtrList::current() const
Returns a pointer to the current list item. The current item may
be 0 (implies that the current index is -1).
\sa at()
*/
/*!
\fn QLNode *QPtrList::currentNode() const
Returns a pointer to the current list node.
The node can be kept and removed later using removeNode(). The
advantage is that the item can be removed directly without
searching the list.
\warning Do not call this function unless you are an expert.
\sa removeNode(), takeNode(), current()
*/
/*!
\fn type *QPtrList::getFirst() const
Returns a pointer to the first item in the list, or 0 if the list
is empty.
This function does not affect the current list item.
\sa first(), getLast()
*/
/*!
\fn type *QPtrList::getLast() const
Returns a pointer to the last item in the list, or 0 if the list
is empty.
This function does not affect the current list item.
\sa last(), getFirst()
*/
/*!
\fn type *QPtrList::first()
Returns a pointer to the first item in the list and makes this the
current list item; returns 0 if the list is empty.
\sa getFirst(), last(), next(), prev(), current()
*/
/*!
\fn type *QPtrList::last()
Returns a pointer to the last item in the list and makes this the
current list item; returns 0 if the list is empty.
\sa getLast(), first(), next(), prev(), current()
*/
/*!
\fn type *QPtrList::next()
Returns a pointer to the item succeeding the current item. Returns
0 if the current item is 0 or equal to the last item.
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.
\sa first(), last(), prev(), current()
*/
/*!
\fn type *QPtrList::prev()
Returns a pointer to the item preceding the current item. Returns
0 if the current item is 0 or equal to the first item.
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.
\sa first(), last(), next(), current()
*/
/*!
\fn void QPtrList::toVector( QGVector *vec ) const
Stores all list items in the vector \a vec.
The vector must be of the same item type, otherwise the result
will be undefined.
*/
/*!
\enum QPtrList::iterator
\internal
*/
/*!
\enum QPtrList::Iterator
\internal
*/
/*!
\enum QPtrList::ConstIterator
\internal
*/
/*!
\enum QPtrList::const_iterator
\internal
*/
/*!
\fn QPtrList::constBegin() const
\internal
*/
/*!
\fn QPtrList::constEnd() const
\internal
*/
/*!
\fn QPtrList::erase(Iterator)
\internal
*/
/*****************************************************************************
QPtrListIterator documentation
*****************************************************************************/
/*!
\class QPtrListIterator
\brief The QPtrListIterator class provides an iterator for
QPtrList collections.
\ingroup collection
\ingroup tools
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 \link
ntqptrlist.html#example example in the QPtrList class documentation
\endlink, but it uses QPtrListIterator. The class Employee is
defined there.
\code
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;
}
\endcode
The output is
\code
Doe, John earns 50000
Williams, Jane earns 80000
Jones, Tom earns 60000
\endcode
Using a list iterator is a more robust way of traversing the list
than using the QPtrList member functions \link QPtrList::first()
first\endlink(), \link QPtrList::next() next\endlink(), \link
QPtrList::current() current\endlink(), 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 modify the list in any way.
When an item is removed from the list, all iterators that point to
that item are updated to point to QPtrList::current() instead to
avoid dangling references.
\sa QPtrList
*/
/*!
\fn QPtrListIterator::QPtrListIterator( const QPtrList<type> &list )
Constructs an iterator for \a list. The current iterator item is
set to point on the first item in the \a list.
*/
/*!
\fn QPtrListIterator::~QPtrListIterator()
Destroys the iterator.
*/
/*!
\fn uint QPtrListIterator::count() const
Returns the number of items in the list this iterator operates on.
\sa isEmpty()
*/
/*!
\fn bool QPtrListIterator::isEmpty() const
Returns TRUE if the list is empty; otherwise returns FALSE.
\sa count()
*/
/*!
\fn bool QPtrListIterator::atFirst() const
Returns TRUE if the current iterator item is the first list item;
otherwise returns FALSE.
\sa toFirst(), atLast()
*/
/*!
\fn bool QPtrListIterator::atLast() const
Returns TRUE if the current iterator item is the last list item;
otherwise returns FALSE.
\sa toLast(), atFirst()
*/
/*!
\fn type *QPtrListIterator::toFirst()
Sets the current iterator item to point to the first list item and
returns a pointer to the item. Sets the current item to 0 and
returns 0 if the list is empty.
\sa toLast(), atFirst()
*/
/*!
\fn type *QPtrListIterator::toLast()
Sets the current iterator item to point to the last list item and
returns a pointer to the item. Sets the current item to 0 and
returns 0 if the list is empty.
\sa toFirst(), atLast()
*/
/*!
\fn QPtrListIterator::operator type *() const
Cast operator. Returns a pointer to the current iterator item.
Same as current().
*/
/*!
\fn type *QPtrListIterator::operator*()
Asterisk operator. Returns a pointer to the current iterator item.
Same as current().
*/
/*!
\fn type *QPtrListIterator::current() const
Returns a pointer to the current iterator item. If the iterator is
positioned before the first item in the list or after the last
item in the list, 0 is returned.
*/
/*!
\fn type *QPtrListIterator::operator()()
Makes the succeeding item current and returns the original current
item.
If the current iterator item was the last item in the list or if
it was 0, 0 is returned.
*/
/*!
\fn type *QPtrListIterator::operator++()
Prefix ++ makes the succeeding item current and returns the new
current item.
If the current iterator item was the last item in the list or if
it was 0, 0 is returned.
*/
/*!
\fn type *QPtrListIterator::operator+=( uint jump )
Sets the current item to the item \a jump positions after the
current item and returns a pointer to that item.
If that item is beyond the last item or if the list is empty, it
sets the current item to 0 and returns 0
*/
/*!
\fn type *QPtrListIterator::operator--()
Prefix - makes the preceding item current and returns the new
current item.
If the current iterator item was the first item in the list or if
it was 0, 0 is returned.
*/
/*!
\fn type *QPtrListIterator::operator-=( uint jump )
Returns the item \a jump positions before the current item or 0
if it is beyond the first item. Makes this the current item.
*/
/*!
\fn QPtrListIterator<type>& QPtrListIterator::operator=( const QPtrListIterator<type> &it )
Assignment. Makes a copy of the iterator \a it and returns a
reference to this iterator.
*/
/*****************************************************************************
QStrList documentation
*****************************************************************************/
/*!
\class QStrList ntqstrlist.h
\brief The QStrList class provides a doubly-linked list of char*.
\ingroup collection
\ingroup tools
\ingroup text
If you want a string list of \l{QString}s use QStringList.
This class is a QPtrList\<char\> instance (a list of char*).
QStrList can make deep or shallow copies of the strings that are
inserted.
A deep copy means that memory is allocated for the string and then
the string data is copied into that memory. A shallow copy is just
a copy of the pointer value and not of the string data itself.
The disadvantage of shallow copies is that because a pointer can
be deleted only once, the program must put all strings in a
central place and know when it is safe to delete them (i.e. when
the strings are no longer referenced by other parts of the
program). This can make the program more complex. The advantage of
shallow copies is that they consume far less memory than deep
copies. It is also much faster to copy a pointer (typically 4 or 8
bytes) than to copy string data.
A QStrList that operates on deep copies will, by default, turn on
auto-deletion (see setAutoDelete()). Thus, by default QStrList
will deallocate any string copies it allocates.
The virtual compareItems() function is reimplemented and does a
case-sensitive string comparison. The inSort() function will
insert strings in sorted order. In general it is fastest to insert
the strings as they come and sort() at the end; inSort() is useful
when you just have to add a few extra strings to an already sorted
list.
The QStrListIterator class is an iterator for QStrList.
*/
/*!
\fn QStrList::QStrList( bool deepCopies )
Constructs an empty list of strings. Will make deep copies of all
inserted strings if \a deepCopies is TRUE, or use shallow copies
if \a deepCopies is FALSE.
*/
/*!
\fn QStrList::QStrList( const QStrList &list )
Constructs a copy of \a list.
If \a list has deep copies, this list will also get deep copies.
Only the pointers are copied (shallow copy) if the other list does
not use deep copies.
*/
/*!
\fn QStrList::~QStrList()
Destroys the list. All strings are removed.
*/
/*!
\fn QStrList& QStrList::operator=( const QStrList& list )
Assigns \a list to this list and returns a reference to this list.
If \a list has deep copies, this list will also get deep copies.
Only the pointers are copied (shallow copy) if the other list does
not use deep copies.
*/
/*****************************************************************************
QStrIList documentation
*****************************************************************************/
/*!
\class QStrIList ntqstrlist.h
\brief The QStrIList class provides a doubly-linked list of char*
with case-insensitive comparison.
\ingroup collection
\ingroup tools
This class is a QPtrList\<char\> instance (a list of char*).
QStrIList is identical to QStrList except that the virtual
compareItems() function is reimplemented to compare strings
case-insensitively. The inSort() function inserts strings in a
sorted order. In general it is fastest to insert the strings as
they come and sort() at the end; inSort() is useful when you just
have to add a few extra strings to an already sorted list.
The QStrListIterator class works for QStrIList.
\sa QStringList
*/
/*!
\fn QStrIList::QStrIList( bool deepCopies )
Constructs a list of strings. Will make deep copies of all
inserted strings if \a deepCopies is TRUE, or use shallow copies
if \a deepCopies is FALSE.
*/
/*!
\fn QStrIList::~QStrIList()
Destroys the list. All strings are removed.
*/
/*!
\fn int QPtrList::compareItems( QPtrCollection::Item item1,
QPtrCollection::Item item2 )
This virtual function compares two list items.
Returns:
\list
\i zero if \a item1 == \a item2
\i nonzero if \a item1 != \a item2
\endlist
This function returns \e int rather than \e bool so that
reimplementations can return three values and use it to sort by:
\list
\i 0 if \a item1 == \a item2
\i \> 0 (positive integer) if \a item1 \> \a item2
\i \< 0 (negative integer) if \a item1 \< \a item2
\endlist
inSort() requires that compareItems() is implemented as described
here.
This function should not modify the list because some const
functions call compareItems().
The default implementation compares the pointers.
*/
/*!
\fn QDataStream& QPtrList::read( QDataStream& s,
QPtrCollection::Item& item )
Reads a list item from the stream \a s and returns a reference to
the stream.
The default implementation sets \a item to 0.
\sa write()
*/
/*!
\fn QDataStream& QPtrList::write( QDataStream& s,
QPtrCollection::Item item ) const
Writes a list item, \a item to the stream \a s and returns a
reference to the stream.
The default implementation does nothing.
\sa read()
*/
/*! \fn iterator QPtrList::begin()
\internal
*/
/*! \fn const_iterator QPtrList::begin() const
\internal
*/
/*! \fn iterator QPtrList::end()
\internal
*/
/*! \fn const_iterator QPtrList::end() const
\internal
*/
/*****************************************************************************
QStrListIterator documentation
*****************************************************************************/
/*!
\class QStrListIterator ntqstrlist.h
\brief The QStrListIterator class is an iterator for the QStrList
and QStrIList classes.
\ingroup tools
This class is a QPtrListIterator\<char\> instance. It can traverse
the strings in the QStrList and QStrIList classes.
*/
/*****************************************************************************
QPtrListAutoDelete documentation
*****************************************************************************/
/*
\class QPtrListAutoDelete
\brief The QPtrListAutoDelete class is a template class that provides a list that auto-deletes its data.
\ingroup collection
\ingroup tools
A QPtrListAutoDelete is identical to a QPtrList with
setAutoDelete(TRUE).
*/