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Please review the following information to ensure ** the GNU Free Documentation License version 1.3 requirements ** will be met: https://www.gnu.org/licenses/fdl-1.3.html. ** $QT_END_LICENSE$ ** ****************************************************************************/ /*! \class QKeyValueIterator \inmodule QtCore \since 5.10 \brief Iterator over the key/value pairs of an associative container. The QKeyValueIterator class provides an STL-style iterator for returning key/value pairs from associative containers like QHash and QMap. It supports the same API as the STL associative containers, i.e. getting a key/value pair when iterating through the container. This will allow for better interoperability between QMap, QHash and friends and STL-style algorithms. \warning Iterators on implicitly shared containers do not work exactly like STL-iterators. You should avoid copying a container while iterators are active on that container. For more information, read \l{Implicit sharing iterator problem}. */ /*! \typedef QKeyValueIterator::iterator_category \internal */ /*! \typedef QKeyValueIterator::difference_type \internal */ /*! \typedef QKeyValueIterator::value_type \internal */ /*! \struct QKeyValueIterator::pointer \internal */ /*! \typedef QKeyValueIterator::reference \internal */ /*! \fn template QKeyValueIterator::QKeyValueIterator() Constructs a default QKeyValueIterator. */ /*! \fn template QKeyValueIterator::QKeyValueIterator(Iterator o) Constructs a QKeyValueIterator on top of \a o. */ /*! \fn template std::pair QKeyValueIterator::operator*() const Returns the current entry as a pair. */ /*! \fn template pointer QKeyValueIterator::operator->() const Returns the current entry as a pointer-like object to the pair. \since 5.15 \sa operator*() */ /*! \fn template bool QKeyValueIterator::operator==(QKeyValueIterator lhs, QKeyValueIterator rhs) Returns \c true if \a rhs points to the same item as \a lhs otherwise returns \c false. \sa operator!=() */ /*! \fn template bool QKeyValueIterator::operator!=(QKeyValueIterator lhs, QKeyValueIterator rhs) Returns \c true if \a rhs points to a different item than \a lhs otherwise returns \c false. \sa operator==() */ /*! \fn template QKeyValueIterator &QKeyValueIterator::operator++() The prefix ++ operator (\c{++i}) advances the iterator to the next item in the container and returns the iterator. \note Advancing the iterator past its container's end() constitutes undefined behavior. \sa operator--() */ /*! \fn template QKeyValueIterator QKeyValueIterator::operator++(int) \overload The postfix ++ operator (\c{i++}) advances the iterator to the next item in the container and returns the iterator's prior value. \note Advancing the iterator past its container's end() constitutes undefined behavior. */ /*! \fn template QKeyValueIterator &QKeyValueIterator::operator--() The prefix -- operator (\c{--i}) backs the iterator up to the previous item in the container and returns the iterator. \note Backing up an iterator to before its container's begin() constitutes undefined behavior. \sa operator++() */ /*! \fn template QKeyValueIterator QKeyValueIterator::operator--(int) \overload The postfix -- operator (\c{i--}) backs the iterator up to the previous item in the container and returns the iterator's prior value. \note Backing up an iterator to before its container's begin() constitutes undefined behavior. */ /*! \fn template Iterator QKeyValueIterator::base() const Returns the underlying iterator this QKeyValueIterator is based on. */ /*! \class QListIterator \inmodule QtCore \brief The QListIterator class provides a Java-style const iterator for QList and QQueue. QList has both \l{Java-style iterators} and \l{STL-style iterators}. STL-style iterators are more efficient and should be preferred. An alternative to using iterators is to use index positions. Most QList member functions take an index as their first parameter, making it possible to access, modify, and remove items without using iterators. QListIterator\ allows you to iterate over a QList\, a QQueue\ or a QStack\. If you want to modify the list as you iterate over it, use QMutableListIterator\ instead. The QListIterator constructor takes a QList as argument. After construction, the iterator is located at the very beginning of the list (before the first item). Here's how to iterate over all the elements sequentially: \snippet code/doc_src_qiterator.cpp 0 The next() function returns the next item in the list and advances the iterator. Unlike STL-style iterators, Java-style iterators point \e between items rather than directly \e at items. The first call to next() advances the iterator to the position between the first and second item, and returns the first item; the second call to next() advances the iterator to the position between the second and third item, and returns the second item; and so on. \image javaiterators1.png Here's how to iterate over the elements in reverse order: \snippet code/doc_src_qiterator.cpp 1 If you want to find all occurrences of a particular value, use findNext() or findPrevious() in a loop. Multiple iterators can be used on the same list. If the list is modified while a QListIterator is active, the QListIterator will continue iterating over the original list, ignoring the modified copy. \sa QMutableListIterator, QList::const_iterator */ /*! \class QSetIterator \inmodule QtCore \brief The QSetIterator class provides a Java-style const iterator for QSet. QSet has both \l{Java-style iterators} and \l{STL-style iterators}. STL-style iterators are more efficient and should be preferred. QSetIterator\ allows you to iterate over a QSet\. If you want to modify the set as you iterate over it, use QMutableSetIterator\ instead. The constructor takes a QSet as argument. After construction, the iterator is located at the very beginning of the set (before the first item). Here's how to iterate over all the elements sequentially: \snippet code/doc_src_qiterator.cpp 6 The next() function returns the next item in the set and advances the iterator. Unlike STL-style iterators, Java-style iterators point \e between items rather than directly \e at items. The first call to next() advances the iterator to the position between the first and second item, and returns the first item; the second call to next() advances the iterator to the position between the second and third item, returning the second item; and so on. \image javaiterators1.png Here's how to iterate over the elements in reverse order: \snippet code/doc_src_qiterator.cpp 7 If you want to find all occurrences of a particular value, use findNext() or findPrevious() in a loop. Multiple iterators can be used on the same set. If the set is modified while a QSetIterator is active, the QSetIterator will continue iterating over the original set, ignoring the modified copy. \sa QMutableSetIterator, QSet::const_iterator */ /*! \class QMutableListIterator \inmodule QtCore \brief The QMutableListIterator class provides a Java-style non-const iterator for QList, QQueue and QStack. QList has both \l{Java-style iterators} and \l{STL-style iterators}. STL-style iterators are more efficient and should be preferred. An alternative to using iterators is to use index positions. Most QList member functions take an index as their first parameter, making it possible to access, insert, and remove items without using iterators. QMutableListIterator\ allows you to iterate over a QList\ (or a QQueue\) and modify the list. If you don't want to modify the list (or have a const QList), use the slightly faster QListIterator\ instead. The QMutableListIterator constructor takes a QList as argument. After construction, the iterator is located at the very beginning of the list (before the first item). Here's how to iterate over all the elements sequentially: \snippet code/doc_src_qiterator.cpp 8 The next() function returns the next item in the list and advances the iterator. Unlike STL-style iterators, Java-style iterators point \e between items rather than directly \e at items. The first call to next() advances the iterator to the position between the first and second item, and returns the first item; the second call to next() advances the iterator to the position between the second and third item, returning the second item; and so on. \image javaiterators1.png Here's how to iterate over the elements in reverse order: \snippet code/doc_src_qiterator.cpp 9 If you want to find all occurrences of a particular value, use findNext() or findPrevious() in a loop. If you want to remove items as you iterate over the list, use remove(). If you want to modify the value of an item, use setValue(). If you want to insert a new item in the list, use insert(). Example: \snippet code/doc_src_qiterator.cpp 10 The example traverses a list, replacing negative numbers with their absolute values, and eliminating zeroes. Only one mutable iterator can be active on a given list at any time. Furthermore, no changes should be done directly to the list while the iterator is active (as opposed to through the iterator), since this could invalidate the iterator and lead to undefined behavior. \sa QListIterator, QList::iterator */ /*! \class QMutableSetIterator \inmodule QtCore \since 4.2 \brief The QMutableSetIterator class provides a Java-style non-const iterator for QSet. QSet has both \l{Java-style iterators} and \l{STL-style iterators}. STL-style iterators are more efficient and should be preferred. QMutableSetIterator\ allows you to iterate over a QSet\ and remove items from the set as you iterate. If you don't want to modify the set (or have a const QSet), use the slightly faster QSetIterator\ instead. The QMutableSetIterator constructor takes a QSet as argument. After construction, the iterator is located at the very beginning of the set (before the first item). Here's how to iterate over all the elements sequentially: \snippet code/doc_src_qiterator.cpp 17 The next() function returns the next item in the set and advances the iterator. Unlike STL-style iterators, Java-style iterators point \e between items rather than directly \e at items. The first call to next() advances the iterator to the position between the first and second item, and returns the first item; the second call to next() advances the iterator to the position between the second and third item, returning the second item; and so on. \image javaiterators1.png If you want to remove items as you iterate over the set, use remove(). Only one mutable iterator can be active on a given set at any time. Furthermore, no changes should be done directly to the set while the iterator is active (as opposed to through the iterator), since this could invalidate the iterator and lead to undefined behavior. \sa QSetIterator, QSet::iterator */ /*! \fn template QListIterator::QListIterator(const QList &list) \fn template QMutableListIterator::QMutableListIterator(QList &list) Constructs an iterator for traversing \a list. The iterator is set to be at the front of the list (before the first item). \sa operator=() */ /*! \fn template QSetIterator::QSetIterator(const QSet &set) \fn template QMutableSetIterator::QMutableSetIterator(QSet &set) Constructs an iterator for traversing \a set. The iterator is set to be at the front of the set (before the first item). \sa operator=() */ /*! \fn template QMutableListIterator &QMutableListIterator::operator=(QList &list) \fn template QListIterator &QListIterator::operator=(const QList &list) Makes the iterator operate on \a list. The iterator is set to be at the front of the list (before the first item). \sa toFront(), toBack() */ /*! \fn template QSetIterator &QSetIterator::operator=(const QSet &set) \fn template QMutableSetIterator &QMutableSetIterator::operator=(QSet &set) Makes the iterator operate on \a set. The iterator is set to be at the front of the set (before the first item). \sa toFront(), toBack() */ /*! \fn template void QListIterator::toFront() \fn template void QSetIterator::toFront() \fn template void QMutableListIterator::toFront() \fn template void QMutableSetIterator::toFront() Moves the iterator to the front of the container (before the first item). \sa toBack(), next() */ /*! \fn template void QListIterator::toBack() \fn template void QSetIterator::toBack() \fn template void QMutableListIterator::toBack() Moves the iterator to the back of the container (after the last item). \sa toFront(), previous() */ /*! \fn template void QMutableSetIterator::toBack() Moves the iterator to the back of the container (after the last item). \sa toFront() */ /*! \fn template bool QListIterator::hasNext() const \fn template bool QSetIterator::hasNext() const \fn template bool QMutableListIterator::hasNext() const Returns \c true if there is at least one item ahead of the iterator, i.e. the iterator is \e not at the back of the container; otherwise returns \c false. \sa hasPrevious(), next() */ /*! \fn template bool QMutableSetIterator::hasNext() const Returns \c true if there is at least one item ahead of the iterator, i.e. the iterator is \e not at the back of the container; otherwise returns \c false. \sa next() */ /*! \fn template const T &QListIterator::next() \fn template const T &QSetIterator::next() Returns the next item and advances the iterator by one position. Calling this function on an iterator located at the back of the container leads to undefined results. \sa hasNext(), peekNext(), previous() */ /* \fn template const T &QMutableSetIterator::next() Returns the next item and advances the iterator by one position. Calling this function on an iterator located at the back of the container leads to undefined results. \sa hasNext(), peekNext() */ /*! \fn template const T &QMutableSetIterator::next() Returns the next item and advances the iterator by one position. Calling this function on an iterator located at the back of the container leads to undefined results. \sa hasNext(), peekNext() */ /*! \fn template T &QMutableListIterator::next() Returns a reference to the next item, and advances the iterator by one position. Calling this function on an iterator located at the back of the container leads to undefined results. \sa hasNext(), peekNext(), previous() */ /*! \fn template const T &QListIterator::peekNext() const \fn template const T &QSetIterator::peekNext() const Returns the next item without moving the iterator. Calling this function on an iterator located at the back of the container leads to undefined results. \sa hasNext(), next(), peekPrevious() */ /*! \fn template const T &QMutableSetIterator::peekNext() const Returns the next item without moving the iterator. Calling this function on an iterator located at the back of the container leads to undefined results. \sa hasNext(), next() */ /*! \fn template T &QMutableListIterator::peekNext() const Returns a reference to the next item, without moving the iterator. Calling this function on an iterator located at the back of the container leads to undefined results. \sa hasNext(), next(), peekPrevious() */ /*! \fn template bool QListIterator::hasPrevious() const \fn template bool QSetIterator::hasPrevious() const \fn template bool QMutableListIterator::hasPrevious() const Returns \c true if there is at least one item behind the iterator, i.e. the iterator is \e not at the front of the container; otherwise returns \c false. \sa hasNext(), previous() */ /*! \fn template const T &QListIterator::previous() \fn template const T &QSetIterator::previous() Returns the previous item and moves the iterator back by one position. Calling this function on an iterator located at the front of the container leads to undefined results. \sa hasPrevious(), peekPrevious(), next() */ /*! \fn template T &QMutableListIterator::previous() Returns a reference to the previous item and moves the iterator back by one position. Calling this function on an iterator located at the front of the container leads to undefined results. \sa hasPrevious(), peekPrevious(), next() */ /*! \fn template const T &QListIterator::peekPrevious() const \fn template const T &QSetIterator::peekPrevious() const Returns the previous item without moving the iterator. Calling this function on an iterator located at the front of the container leads to undefined results. \sa hasPrevious(), previous(), peekNext() */ /*! \fn template T &QMutableListIterator::peekPrevious() const Returns a reference to the previous item, without moving the iterator. Calling this function on an iterator located at the front of the container leads to undefined results. \sa hasPrevious(), previous(), peekNext() */ /*! \fn template bool QMutableSetIterator::findNext(const T &value) Searches for \a value starting from the current iterator position forward. Returns \c true if \a value is found; otherwise returns \c false. After the call, if \a value was found, the iterator is positioned just after the matching item; otherwise, the iterator is positioned at the back of the container. */ /*! \fn template bool QListIterator::findNext(const T &value) \fn template bool QSetIterator::findNext(const T &value) \fn template bool QMutableListIterator::findNext(const T &value) Searches for \a value starting from the current iterator position forward. Returns \c true if \a value is found; otherwise returns \c false. After the call, if \a value was found, the iterator is positioned just after the matching item; otherwise, the iterator is positioned at the back of the container. \sa findPrevious() */ /*! \fn template bool QListIterator::findPrevious(const T &value) \fn template bool QSetIterator::findPrevious(const T &value) \fn template bool QMutableListIterator::findPrevious(const T &value) Searches for \a value starting from the current iterator position backward. Returns \c true if \a value is found; otherwise returns false. After the call, if \a value was found, the iterator is positioned just before the matching item; otherwise, the iterator is positioned at the front of the container. \sa findNext() */ /*! \fn template void QMutableListIterator::remove() Removes the last item that was jumped over using one of the traversal functions (next(), previous(), findNext(), findPrevious()). Example: \snippet code/doc_src_qiterator.cpp 19 \sa insert(), setValue() */ /*! \fn template void QMutableSetIterator::remove() Removes the last item that was jumped over using one of the traversal functions (next(), findNext()). Example: \snippet code/doc_src_qiterator.cpp 22 \sa value() */ /*! \fn template void QMutableListIterator::setValue(const T &value) const Replaces the value of the last item that was jumped over using one of the traversal functions with \a value. The traversal functions are next(), previous(), findNext(), and findPrevious(). Example: \snippet code/doc_src_qiterator.cpp 23 \sa value(), remove(), insert() */ /*! \fn template const T &QMutableListIterator::value() const Returns the value of the last item that was jumped over using one of the traversal functions (next(), previous(), findNext(), findPrevious()). After a call to next() or findNext(), value() is equivalent to peekPrevious(). After a call to previous() or findPrevious(), value() is equivalent to peekNext(). */ /*! \fn template const T &QMutableSetIterator::value() const Returns the value of the last item that was jumped over using next() or findNext(). */ /*! \fn template T &QMutableListIterator::value() \overload Returns a non-const reference to the value of the last item that was jumped over using one of the traversal functions. */ /*! \fn template void QMutableListIterator::insert(const T &value) Inserts \a value at the current iterator position. After the call, the iterator is located just after the inserted item. \sa remove(), setValue() */ /*! \class QMapIterator \inmodule QtCore \brief The QMapIterator class provides a Java-style const iterator for QMap. QMap has both \l{Java-style iterators} and \l{STL-style iterators}. STL-style iterators are more efficient and should be preferred. QMapIterator\ allows you to iterate over a QMap. If you want to modify the map as you iterate over it, use QMutableMapIterator instead. The QMapIterator constructor takes a QMap as argument. After construction, the iterator is located at the very beginning of the map (before the first item). Here's how to iterate over all the elements sequentially: \snippet code/doc_src_qiterator.cpp 26 The next() function returns the next item in the map and advances the iterator. The key() and value() functions return the key and value of the last item that was jumped over. Unlike STL-style iterators, Java-style iterators point \e between items rather than directly \e at items. The first call to next() advances the iterator to the position between the first and second item, and returns the first item; the second call to next() advances the iterator to the position between the second and third item; and so on. \image javaiterators1.png Here's how to iterate over the elements in reverse order: \snippet code/doc_src_qiterator.cpp 27 If you want to find all occurrences of a particular value, use findNext() or findPrevious() in a loop. For example: \snippet code/doc_src_qiterator.cpp 28 Multiple iterators can be used on the same map. If the map is modified while a QMapIterator is active, the QMapIterator will continue iterating over the original map, ignoring the modified copy. \sa QMutableMapIterator, QMap::const_iterator */ /*! \class QMultiMapIterator \inmodule QtCore \brief The QMultiMapIterator class provides a Java-style const iterator for QMultiMap. QMultiMap has both \l{Java-style iterators} and \l{STL-style iterators}. STL-style iterators are more efficient and should be preferred. QMultiMapIterator\ allows you to iterate over a QMultiMap. If you want to modify the map as you iterate over it, use QMutableMultiMapIterator instead. The QMultiMapIterator constructor takes a QMultiMap as argument. After construction, the iterator is located at the very beginning of the map (before the first item). Here's how to iterate over all the elements sequentially: \snippet code/doc_src_qiterator.cpp 26multi The next() function returns the next item in the map and advances the iterator. The key() and value() functions return the key and value of the last item that was jumped over. Unlike STL-style iterators, Java-style iterators point \e between items rather than directly \e at items. The first call to next() advances the iterator to the position between the first and second item, and returns the first item; the second call to next() advances the iterator to the position between the second and third item; and so on. \image javaiterators1.png Here's how to iterate over the elements in reverse order: \snippet code/doc_src_qiterator.cpp 27multi If you want to find all occurrences of a particular value, use findNext() or findPrevious() in a loop. For example: \snippet code/doc_src_qiterator.cpp 28multi Multiple iterators can be used on the same map. If the map is modified while a QMultiMapIterator is active, the QMultiMapIterator will continue iterating over the original map, ignoring the modified copy. \sa QMutableMultiMapIterator */ /*! \class QHashIterator \inmodule QtCore \brief The QHashIterator class provides a Java-style const iterator for QHash and QMultiHash. QHash has both \l{Java-style iterators} and \l{STL-style iterators}. STL-style iterators are more efficient and should be preferred. QHashIterator\ allows you to iterate over a QHash (or a QMultiHash). If you want to modify the hash as you iterate over it, use QMutableHashIterator instead. The QHashIterator constructor takes a QHash as argument. After construction, the iterator is located at the very beginning of the hash (before the first item). Here's how to iterate over all the elements sequentially: \snippet code/doc_src_qiterator.cpp 29 The next() function returns the next item in the hash and advances the iterator. The key() and value() functions return the key and value of the last item that was jumped over. Unlike STL-style iterators, Java-style iterators point \e between items rather than directly \e at items. The first call to next() advances the iterator to the position between the first and second item, and returns the first item; the second call to next() advances the iterator to the position between the second and third item; and so on. \image javaiterators1.png If you want to find all occurrences of a particular value, use findNext() in a loop. For example: \snippet code/doc_src_qiterator.cpp 31 Multiple iterators can be used on the same hash. If the hash is modified while a QHashIterator is active, the QHashIterator will continue iterating over the original hash, ignoring the modified copy. \sa QMutableHashIterator, QHash::const_iterator */ /*! \class QMutableMapIterator \inmodule QtCore \brief The QMutableMapIterator class provides a Java-style non-const iterator for QMap. QMap has both \l{Java-style iterators} and \l{STL-style iterators}. STL-style iterators are more efficient and should be preferred. QMutableMapIterator\ allows you to iterate over a QMap and modify the map. If you don't want to modify the map (or have a const QMap), use the slightly faster QMapIterator instead. The QMutableMapIterator constructor takes a QMap as argument. After construction, the iterator is located at the very beginning of the map (before the first item). Here's how to iterate over all the elements sequentially: \snippet code/doc_src_qiterator.cpp 32 The next() function returns the next item in the map and advances the iterator. The key() and value() functions return the key and value of the last item that was jumped over. Unlike STL-style iterators, Java-style iterators point \e between items rather than directly \e at items. The first call to next() advances the iterator to the position between the first and second item, and returns the first item; the second call to next() advances the iterator to the position between the second and third item; and so on. \image javaiterators1.png Here's how to iterate over the elements in reverse order: \snippet code/doc_src_qiterator.cpp 33 If you want to find all occurrences of a particular value, use findNext() or findPrevious() in a loop. For example: \snippet code/doc_src_qiterator.cpp 34 If you want to remove items as you iterate over the map, use remove(). If you want to modify the value of an item, use setValue(). Example: \snippet code/doc_src_qiterator.cpp 35 The example removes all (key, value) pairs where the key and the value are the same. Only one mutable iterator can be active on a given map at any time. Furthermore, no changes should be done directly to the map while the iterator is active (as opposed to through the iterator), since this could invalidate the iterator and lead to undefined behavior. \sa QMapIterator, QMap::iterator */ /*! \class QMutableMultiMapIterator \inmodule QtCore \brief The QMutableMultiMapIterator class provides a Java-style non-const iterator for QMultiMap. QMultiMap has both \l{Java-style iterators} and \l{STL-style iterators}. STL-style iterators are more efficient and should be preferred. QMutableMultiMapIterator\ allows you to iterate over a QMultiMap and modify the map. If you don't want to modify the map (or have a const QMultiMap), use the slightly faster QMultiMapIterator instead. The QMutableMultiMapIterator constructor takes a QMultiMap as argument. After construction, the iterator is located at the very beginning of the map (before the first item). Here's how to iterate over all the elements sequentially: \snippet code/doc_src_qiterator.cpp 32multi The next() function returns the next item in the map and advances the iterator. The key() and value() functions return the key and value of the last item that was jumped over. Unlike STL-style iterators, Java-style iterators point \e between items rather than directly \e at items. The first call to next() advances the iterator to the position between the first and second item, and returns the first item; the second call to next() advances the iterator to the position between the second and third item; and so on. \image javaiterators1.png Here's how to iterate over the elements in reverse order: \snippet code/doc_src_qiterator.cpp 33multi If you want to find all occurrences of a particular value, use findNext() or findPrevious() in a loop. For example: \snippet code/doc_src_qiterator.cpp 34multi If you want to remove items as you iterate over the map, use remove(). If you want to modify the value of an item, use setValue(). Example: \snippet code/doc_src_qiterator.cpp 35multi The example removes all (key, value) pairs where the key and the value are the same. Only one mutable iterator can be active on a given map at any time. Furthermore, no changes should be done directly to the map while the iterator is active (as opposed to through the iterator), since this could invalidate the iterator and lead to undefined behavior. \sa QMultiMapIterator, QMultiMap::iterator */ /*! \class QMutableHashIterator \inmodule QtCore \brief The QMutableHashIterator class provides a Java-style non-const iterator for QHash and QMultiHash. QHash has both \l{Java-style iterators} and \l{STL-style iterators}. STL-style iterators are more efficient and should be preferred. QMutableHashIterator\ allows you to iterate over a QHash (or a QMultiHash) and modify the hash. If you don't want to modify the hash (or have a const QHash), use the slightly faster QHashIterator instead. The QMutableHashIterator constructor takes a QHash as argument. After construction, the iterator is located at the very beginning of the hash (before the first item). Here's how to iterate over all the elements sequentially: \snippet code/doc_src_qiterator.cpp 36 The next() function returns the next item in the hash and advances the iterator. The key() and value() functions return the key and value of the last item that was jumped over. Unlike STL-style iterators, Java-style iterators point \e between items rather than directly \e at items. The first call to next() advances the iterator to the position between the first and second item, and returns the first item; the second call to next() advances the iterator to the position between the second and third item; and so on. \image javaiterators1.png If you want to find all occurrences of a particular value, use findNext() in a loop. For example: \snippet code/doc_src_qiterator.cpp 38 If you want to remove items as you iterate over the hash, use remove(). If you want to modify the value of an item, use setValue(). Example: \snippet code/doc_src_qiterator.cpp 39 The example removes all (key, value) pairs where the key and the value are the same. Only one mutable iterator can be active on a given hash at any time. Furthermore, no changes should be done directly to the hash while the iterator is active (as opposed to through the iterator), since this could invalidate the iterator and lead to undefined behavior. \sa QHashIterator, QHash::iterator */ /*! \fn template QMapIterator::QMapIterator(const QMap &map) \fn template QMutableMapIterator::QMutableMapIterator(QMap &map) \fn template QMultiMapIterator::QMultiMapIterator(const QMultiMap &map) \fn template QMutableMultiMapIterator::QMutableMultiMapIterator(QMultiMap &map) Constructs an iterator for traversing \a map. The iterator is set to be at the front of the map (before the first item). \sa operator=() */ /*! \fn template QHashIterator::QHashIterator(const QHash &hash) \fn template QMutableHashIterator::QMutableHashIterator(QHash &hash) Constructs an iterator for traversing \a hash. The iterator is set to be at the front of the hash (before the first item). \sa operator=() */ /*! \fn template QMapIterator &QMapIterator::operator=(const QMap &map) \fn template QMutableMapIterator &QMutableMapIterator::operator=(QMap &map) \fn template QMultiMapIterator &QMultiMapIterator::operator=(const QMultiMap &map) \fn template QMutableMultiMapIterator &QMutableMultiMapIterator::operator=(QMultiMap &map) Makes the iterator operate on \a map. The iterator is set to be at the front of the map (before the first item). \sa toFront(), toBack() */ /*! \fn template QHashIterator &QHashIterator::operator=(const QHash &hash) \fn template QMutableHashIterator &QMutableHashIterator::operator=(QHash &hash) Makes the iterator operate on \a hash. The iterator is set to be at the front of the hash (before the first item). \sa toFront(), toBack() */ /*! \fn template void QMapIterator::toFront() \fn template void QMultiMapIterator::toFront() \fn template void QHashIterator::toFront() \fn template void QMutableMapIterator::toFront() \fn template void QMutableMultiMapIterator::toFront() \fn template void QMutableHashIterator::toFront() Moves the iterator to the front of the container (before the first item). \sa toBack(), next() */ /*! \fn template void QMapIterator::toBack() \fn template void QMultiMapIterator::toBack() \fn template void QMutableMapIterator::toBack() \fn template void QMutableMultiMapIterator::toBack() Moves the iterator to the back of the container (after the last item). \sa toFront(), previous() */ /*! \fn template void QHashIterator::toBack() \fn template void QMutableHashIterator::toBack() Moves the iterator to the back of the container (after the last item). \sa toFront() */ /*! \fn template bool QMapIterator::hasNext() const \fn template bool QMultiMapIterator::hasNext() const \fn template bool QMutableMapIterator::hasNext() const \fn template bool QMutableMultiMapIterator::hasNext() const Returns \c true if there is at least one item ahead of the iterator, i.e. the iterator is \e not at the back of the container; otherwise returns \c false. \sa hasPrevious(), next() */ /*! \fn template bool QHashIterator::hasNext() const \fn template bool QMutableHashIterator::hasNext() const Returns \c true if there is at least one item ahead of the iterator, i.e. the iterator is \e not at the back of the container; otherwise returns \c false. \sa next() */ /*! \fn template QMapIterator::Item QMapIterator::next() \fn template QMultiMapIterator::Item QMultiMapIterator::next() Returns the next item and advances the iterator by one position. Call key() on the return value to obtain the item's key, and value() to obtain the value. Calling this function on an iterator located at the back of the container leads to undefined results. \sa hasNext(), {QMapIterator::}{peekNext()}, previous() */ /*! \fn template QMutableMapIterator::Item QMutableMapIterator::next() \fn template QMutableMultiMapIterator::Item QMutableMultiMapIterator::next() Returns the next item and advances the iterator by one position. Call key() on the return value to obtain the item's key, and value() to obtain the value. Calling this function on an iterator located at the back of the container leads to undefined results. \sa hasNext(), peekNext(), previous() */ /*! \fn template QHashIterator::Item QHashIterator::next() Returns the next item and advances the iterator by one position. Call key() on the return value to obtain the item's key, and value() to obtain the value. Calling this function on an iterator located at the back of the container leads to undefined results. \sa hasNext(), peekNext() */ /*! \fn template QMutableHashIterator::Item QMutableHashIterator::next() Returns the next item and advances the iterator by one position. Call key() on the return value to obtain the item's key, and value() to obtain the value. Calling this function on an iterator located at the back of the container leads to undefined results. \sa hasNext(), peekNext() */ /*! \fn template QMapIterator::Item QMapIterator::peekNext() const \fn template QMutableMapIterator::Item QMutableMapIterator::peekNext() const Returns the next item without moving the iterator. Call key() on the return value to obtain the item's key, and value() to obtain the value. Calling this function on an iterator located at the back of the container leads to undefined results. \sa hasNext(), next(), peekPrevious() */ /*! \fn template QMutableMapIterator::Item QMutableMapIterator::peekNext() const \fn template QMutableMultiMapIterator::Item QMutableMultiMapIterator::peekNext() const Returns a reference to the next item without moving the iterator. Call key() on the return value to obtain the item's key, and value() to obtain the value. Calling this function on an iterator located at the back of the container leads to undefined results. \sa hasNext(), next(), peekPrevious() */ /*! \fn template QHashIterator::Item QHashIterator::peekNext() const Returns the next item without moving the iterator. Call key() on the return value to obtain the item's key, and value() to obtain the value. Calling this function on an iterator located at the back of the container leads to undefined results. \sa hasNext(), next() */ /*! \fn template QMutableHashIterator::Item QMutableHashIterator::peekNext() const Returns a reference to the next item without moving the iterator. Call key() on the return value to obtain the item's key, and value() to obtain the value. Calling this function on an iterator located at the back of the container leads to undefined results. \sa hasNext(), next() */ /*! \fn template bool QMapIterator::hasPrevious() const \fn template bool QMultiMapIterator::hasPrevious() const \fn template bool QMutableMapIterator::hasPrevious() const \fn template bool QMutableMultiMapIterator::hasPrevious() const Returns \c true if there is at least one item behind the iterator, i.e. the iterator is \e not at the front of the container; otherwise returns \c false. \sa hasNext(), previous() */ /*! \fn template QMapIterator::Item QMapIterator::previous() \fn template QMutableMapIterator::Item QMutableMapIterator::previous() \fn template QMultiMapIterator::Item QMultiMapIterator::previous() \fn template QMutableMultiMapIterator::Item QMutableMultiMapIterator::previous() Returns the previous item and moves the iterator back by one position. Call key() on the return value to obtain the item's key, and value() to obtain the value. Calling this function on an iterator located at the front of the container leads to undefined results. \sa hasPrevious(), peekPrevious(), next() */ /*! \fn template QMapIterator::Item QMapIterator::peekPrevious() const \fn template QMutableMapIterator::Item QMutableMapIterator::peekPrevious() const \fn template QMultiMapIterator::Item QMultiMapIterator::peekPrevious() const \fn template QMutableMultiMapIterator::Item QMutableMultiMapIterator::peekPrevious() const Returns the previous item without moving the iterator. Call key() on the return value to obtain the item's key, and value() to obtain the value. Calling this function on an iterator located at the front of the container leads to undefined results. \sa hasPrevious(), previous(), {QMapIterator::}{peekNext()} */ /*! \fn template const T &QMapIterator::value() const \fn template const T &QMultiMapIterator::value() const Returns the value of the last item that was jumped over using one of the traversal functions (next(), previous(), findNext(), findPrevious()). After a call to next() or findNext(), value() is equivalent to peekPrevious().value(). After a call to previous() or findPrevious(), value() is equivalent to peekNext().value(). \sa key() */ /*! \fn template const T &QMutableMapIterator::value() const \fn template const T &QMutableMultiMapIterator::value() const Returns the value of the last item that was jumped over using one of the traversal functions (next(), previous(), findNext(), findPrevious()). After a call to next() or findNext(), value() is equivalent to peekPrevious().value(). After a call to previous() or findPrevious(), value() is equivalent to peekNext().value(). \sa key(), setValue() */ /*! \fn template const T &QHashIterator::value() const Returns the value of the last item that was jumped over using one of the traversal functions (next(), findNext()). \sa key() */ /*! \fn template const T &QMutableHashIterator::value() const Returns the value of the last item that was jumped over using one of the traversal functions (next(), findNext()). \sa key(), setValue() */ /*! \fn template T &QMutableMapIterator::value() \fn template T &QMutableMultiMapIterator::value() \fn template T &QMutableHashIterator::value() \overload Returns a non-const reference to the value of the last item that was jumped over using one of the traversal functions. */ /*! \fn template const Key &QMapIterator::key() const \fn template const Key &QMutableMapIterator::key() const \fn template const Key &QMultiMapIterator::key() const \fn template const Key &QMutableMultiMapIterator::key() const Returns the key of the last item that was jumped over using one of the traversal functions (next(), previous(), findNext(), findPrevious()). After a call to next() or findNext(), key() is equivalent to peekPrevious().key(). After a call to previous() or findPrevious(), key() is equivalent to peekNext().key(). \sa value() */ /*! \fn template const Key &QHashIterator::key() const \fn template const Key &QMutableHashIterator::key() const Returns the key of the last item that was jumped over using one of the traversal functions (next(), findNext()). \sa value() */ /*! \fn template bool QMapIterator::findNext(const T &value) \fn template bool QMutableMapIterator::findNext(const T &value) \fn template bool QMultiMapIterator::findNext(const T &value) \fn template bool QMutableMultiMapIterator::findNext(const T &value) Searches for \a value starting from the current iterator position forward. Returns \c true if a (key, value) pair with value \a value is found; otherwise returns \c false. After the call, if \a value was found, the iterator is positioned just after the matching item; otherwise, the iterator is positioned at the back of the container. \sa findPrevious() */ /*! \fn template bool QHashIterator::findNext(const T &value) \fn template bool QMutableHashIterator::findNext(const T &value) Searches for \a value starting from the current iterator position forward. Returns \c true if a (key, value) pair with value \a value is found; otherwise returns \c false. After the call, if \a value was found, the iterator is positioned just after the matching item; otherwise, the iterator is positioned at the back of the container. */ /*! \fn template bool QMapIterator::findPrevious(const T &value) \fn template bool QMutableMapIterator::findPrevious(const T &value) \fn template bool QMultiMapIterator::findPrevious(const T &value) \fn template bool QMutableMultiMapIterator::findPrevious(const T &value) Searches for \a value starting from the current iterator position backward. Returns \c true if a (key, value) pair with value \a value is found; otherwise returns \c false. After the call, if \a value was found, the iterator is positioned just before the matching item; otherwise, the iterator is positioned at the front of the container. \sa findNext() */ /*! \fn template void QMutableMapIterator::remove() \fn template void QMutableMultiMapIterator::remove() Removes the last item that was jumped over using one of the traversal functions (next(), previous(), findNext(), findPrevious()). \sa setValue() */ /*! \fn template void QMutableHashIterator::remove() Removes the last item that was jumped over using one of the traversal functions (next(), findNext()). \sa setValue() */ /*! \fn template void QMutableMapIterator::setValue(const T &value) \fn template void QMutableMultiMapIterator::setValue(const T &value) Replaces the value of the last item that was jumped over using one of the traversal functions with \a value. The traversal functions are next(), previous(), findNext(), and findPrevious(). \sa key(), value(), remove() */ /*! \fn template void QMutableHashIterator::setValue(const T &value) Replaces the value of the last item that was jumped over using one of the traversal functions with \a value. The traversal functions are next() and findNext(). \sa key(), value(), remove() */