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diff --git a/doc/qptrdict.doc b/doc/qptrdict.doc new file mode 100644 index 000000000..df63de645 --- /dev/null +++ b/doc/qptrdict.doc @@ -0,0 +1,458 @@ +/**************************************************************************** +** +** QPtrDict and QPtrDictIterator class documentation +** +** Copyright (C) 1992-2008 Trolltech ASA. All rights reserved. +** +** This file is part of the Qt 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 +** publicly approved by Trolltech ASA (or its successors, if any) +** and the KDE Free Qt Foundation. +** +** Please review the following information to ensure GNU General +** Public Licensing retquirements will be met: +** http://trolltech.com/products/qt/licenses/licensing/opensource/. +** If you are unsure which license is appropriate for your use, please +** review the following information: +** http://trolltech.com/products/qt/licenses/licensing/licensingoverview +** or contact the sales department at [email protected]. +** +** This file may be used under the terms of the Q Public License as +** defined by Trolltech ASA and appearing in the file LICENSE.QPL +** included in the packaging of this file. Licensees holding valid Qt +** Commercial licenses may use this file in accordance with the Qt +** Commercial License Agreement provided with the Software. +** +** This file is provided "AS IS" with NO WARRANTY OF ANY KIND, +** INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR +** A PARTICULAR PURPOSE. Trolltech reserves all rights not granted +** herein. +** +**********************************************************************/ + + +/***************************************************************************** + QPtrDict documentation + *****************************************************************************/ + +/*! + \class QPtrDict + \brief The QPtrDict class is a template class that provides a dictionary based on void* keys. + + \ingroup collection + \ingroup tools + + \important autoDelete setAutoDelete + + QPtrDict is implemented as a template class. Define a template + instance QPtrDict\<X\> to create a dictionary that operates on + pointers to X (X*). + + 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. + + Example: + \code + QPtrDict<char> fields; // void* keys, char* values + + QLineEdit *le1 = new QLineEdit( this ); + le1->setText( "Simpson" ); + QLineEdit *le2 = new QLineEdit( this ); + le2->setText( "Homer" ); + QLineEdit *le3 = new QLineEdit( this ); + le3->setText( "45" ); + + fields.insert( le1, "Surname" ); + fields.insert( le2, "Forename" ); + fields.insert( le3, "Age" ); + + QPtrDictIterator<char> it( fields ); + for( ; it.current(); ++it ) + cout << it.current() << endl; + cout << endl; + + if ( fields[le1] ) // Prints "Surname: Simpson" + cout << fields[le1] << ": " << le1->text() << endl; + if ( fields[le2] ) // Prints "Forename: Homer" + cout << fields[le2] << ": " << le2->text() << endl; + + fields.remove( le1 ); // Removes le1 from the dictionary + cout << le1->text() << endl; // Prints "Simpson" + \endcode + In this example we use a dictionary to add an extra property (a + char*) to the line edits we're using. + + See QDict for full details, including the choice of dictionary + size, and how deletions are handled. + + \sa QPtrDictIterator, QDict, QAsciiDict, QIntDict, + \link collection.html Collection Classes\endlink +*/ + + +/*! + \fn QPtrDict::QPtrDict( int size ) + + Constructs a dictionary using an internal hash array with the size + \a size. + + Setting \a size to a suitably large prime number (equal to or + greater than the expected number of entries) makes the hash + distribution better and improves lookup performance. +*/ + +/*! + \fn QPtrDict::QPtrDict( const QPtrDict<type> &dict ) + + Constructs a copy of \a dict. + + Each item in \a dict is inserted into this dictionary. Only the + pointers are copied (shallow copy). +*/ + +/*! + \fn QPtrDict::~QPtrDict() + + Removes all items from the dictionary and destroys it. + + All iterators that access this dictionary will be reset. + + \sa setAutoDelete() +*/ + +/*! + \fn QPtrDict<type> &QPtrDict::operator=(const QPtrDict<type> &dict) + + Assigns \a dict to this dictionary and returns a reference to this + dictionary. + + This dictionary is first cleared and then each item in \a dict is + inserted into the dictionary. Only the pointers are copied + (shallow copy), unless newItem() has been reimplemented. +*/ + +/*! + \fn uint QPtrDict::count() const + + Returns the number of items in the dictionary. + + \sa isEmpty() +*/ + +/*! + \fn uint QPtrDict::size() const + + Returns the size of the internal hash table (as specified in the + constructor). + + \sa count() +*/ + +/*! + \fn void QPtrDict::resize( uint newsize ) + + Changes the size of the hash table to \a newsize. The contents of + the dictionary are preserved, but all iterators on the dictionary + become invalid. +*/ + +/*! + \fn bool QPtrDict::isEmpty() const + + Returns TRUE if the dictionary is empty; otherwise returns FALSE. + + \sa count() +*/ + +/*! + \fn void QPtrDict::insert( void *key, const type *item ) + + Inserts the \a key with the \a item into the dictionary. + + Multiple items can have the same key, in which case only the last + item will be accessible using \l operator[](). + + \a item may not be 0. + + \sa replace() +*/ + +/*! + \fn void QPtrDict::replace( void *key, const type *item ) + + If the dictionary has key \a key, this key's item is replaced with + \a item. If the dictionary doesn't contain key \a key, \a item is + inserted into the dictionary using key \a key. + + \a item may not be 0. + + Equivalent to + \code + QPtrDict<ItemType> dict; + ... + if ( dict.find( key ) ) + dict.remove( key ); + dict.insert( key, item ); + \endcode + + If there are two or more items with equal keys, then the most + recently inserted item will be replaced. + + \sa insert() +*/ + +/*! + \fn bool QPtrDict::remove( void *key ) + + Removes the item associated with \a key from the dictionary. + Returns TRUE if successful, i.e. if \a key is in the dictionary; + otherwise returns FALSE. + + If there are two or more items with equal keys, then the most + recently inserted item will be removed. + + The removed item is deleted if \link + QPtrCollection::setAutoDelete() auto-deletion\endlink is enabled. + + All dictionary iterators that refer to the removed item will be + set to point to the next item in the dictionary traversal order. + + \sa take(), clear(), setAutoDelete() +*/ + +/*! + \fn type *QPtrDict::take( void *key ) + + Takes the item associated with \a key out of the dictionary + without deleting it (even if \link QPtrCollection::setAutoDelete() + auto-deletion\endlink is enabled). + + If there are two or more items with equal keys, then the most + recently inserted item will be removed. + + Returns a pointer to the item taken out, or 0 if the key does not + exist in the dictionary. + + All dictionary iterators that refer to the taken item will be set + to point to the next item in the dictionary traversal order. + + \sa remove(), clear(), setAutoDelete() +*/ + +/*! + \fn void QPtrDict::clear() + + Removes all items from the dictionary. + + The removed items are deleted if \link + QPtrCollection::setAutoDelete() auto-deletion\endlink is enabled. + + All dictionary iterators that access this dictionary will be + reset. + + \sa remove(), take(), setAutoDelete() +*/ + +/*! + \fn type *QPtrDict::find( void *key ) const + + Returns the item associated with \a key, or 0 if the key does not + exist in the dictionary. + + If there are two or more items with equal keys, then the most + recently inserted item will be found. + + Equivalent to operator[]. + + \sa operator[]() +*/ + +/*! + \fn type *QPtrDict::operator[]( void *key ) const + + Returns the item associated with \a key, or 0 if the key does not + exist in the dictionary. + + If there are two or more items with equal keys, then the most + recently inserted item will be found. + + Equivalent to the find() function. + + \sa find() +*/ + +/*! + \fn void QPtrDict::statistics() const + + Debugging-only function that prints out the dictionary + distribution using qDebug(). +*/ + +/*! + \fn QDataStream& QPtrDict::read( QDataStream &s, QPtrCollection::Item &item ) + + Reads a dictionary 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& QPtrDict::write( QDataStream &s, QPtrCollection::Item ) const + + Writes a dictionary item to the stream \a s and returns a + reference to the stream. + + \sa read() +*/ + +/***************************************************************************** + QPtrDictIterator documentation + *****************************************************************************/ + +/*! + \class QPtrDictIterator qptrdict.h + \brief The QPtrDictIterator class provides an iterator for QPtrDict collections. + + \ingroup collection + \ingroup tools + + QPtrDictIterator is implemented as a template class. Define a + template instance QPtrDictIterator\<X\> to create a dictionary + iterator that operates on QPtrDict\<X\> (dictionary of X*). + + Example: + \code + QPtrDict<char> fields; + + QLineEdit *le1 = new QLineEdit( this ); + le1->setText( "Simpson" ); + QLineEdit *le2 = new QLineEdit( this ); + le2->setText( "Homer" ); + QLineEdit *le3 = new QLineEdit( this ); + le3->setText( "45" ); + + fields.insert( le1, "Surname" ); + fields.insert( le2, "Forename" ); + fields.insert( le3, "Age" ); + + QPtrDictIterator<char> it( fields ); + for( ; it.current(); ++it ) { + QLineEdit *le = (QLineEdit)it.currentKey(); + cout << it.current() << ": " << le->text() << endl; + } + cout << endl; + + // Output (random order): + // Forename: Homer + // Age: 45 + // Surname: Simpson + \endcode + In the example we insert some line edits into a dictionary, + associating a string with each. We then iterate over the + dictionary printing the associated strings. + + Multiple iterators may independently traverse the same dictionary. + A QPtrDict knows about all the iterators that are operating on the + dictionary. When an item is removed from the dictionary, QPtrDict + updates all iterators that refer the removed item to point to the + next item in the traversing order. + + \sa QPtrDict +*/ + +/*! + \fn QPtrDictIterator::QPtrDictIterator( const QPtrDict<type> &dict ) + + Constructs an iterator for \a dict. The current iterator item is + set to point on the first item in the \a dict. +*/ + +/*! + \fn QPtrDictIterator::~QPtrDictIterator() + + Destroys the iterator. +*/ + +/*! + \fn uint QPtrDictIterator::count() const + + Returns the number of items in the dictionary this iterator + operates on. + + \sa isEmpty() +*/ + +/*! + \fn bool QPtrDictIterator::isEmpty() const + + Returns TRUE if the dictionary is empty; otherwise returns FALSE. + + \sa count() +*/ + +/*! + \fn type *QPtrDictIterator::toFirst() + + Sets the current iterator item to point to the first item in the + dictionary and returns a pointer to the item. If the dictionary is + empty, it sets the current item to 0 and returns 0. +*/ + +/*! + \fn QPtrDictIterator::operator type *() const + + Cast operator. Returns a pointer to the current iterator item. + Same as current(). +*/ + +/*! + \fn type *QPtrDictIterator::current() const + + Returns a pointer to the current iterator item's value. +*/ + +/*! + \fn void *QPtrDictIterator::currentKey() const + + Returns the current iterator item's key. +*/ + +/*! + \fn type *QPtrDictIterator::operator()() + + Makes the succeeding item current and returns the original current + item. + + If the current iterator item was the last item in the dictionary + or if it was 0, 0 is returned. +*/ + +/*! + \fn type *QPtrDictIterator::operator++() + + Prefix ++ makes the succeeding item current and returns the new + current item. + + If the current iterator item was the last item in the dictionary + or if it was 0, 0 is returned. +*/ + +/*! + \fn type *QPtrDictIterator::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 dictionary is + empty, it sets the current item to 0 and returns 0. +*/ |