QMutableListIterator Class The QMutableListIterator class provides a Java-style non-const iterator for QList and QQueue. More...  
 Header:
 #include <QMutableListIterator> 


 qmake:
 QT += core


 List of all members, including inherited members  Public Functions  
 

QMutableListIterator(QList<T> &list)
 
 bool 

findNext(const T &value)
 
 bool 

findPrevious(const T &value)
 
 bool 

hasNext() const
 
 bool 

hasPrevious() const
 
 void 

insert(const T &value)
 
 T &

next()
 
 T &

peekNext() const
 
 T &

peekPrevious() const
 
 T &

previous()
 
 void 

remove()
 
 void 

setValue(const T &value) const
 
 void 

toBack()
 
 void 

toFront()
 
 const T &

value() const
 
 T &

value()
 
 QMutableListIterator &

operator=(QList<T> &list)
  Detailed Description The QMutableListIterator class provides a Java-style non-const iterator for QList and QQueue. QList has both Java-style iterators and STL-style iterators. The Java-style iterators are more high-level and easier to use than the STL-style iterators; on the other hand, they are slightly less efficient. 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<T> allows you to iterate over a QList<T> (or a QQueue<T>) and modify the list. If you don't want to modify the list (or have a const QList), use the slightly faster QListIterator<T> 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: QList<float> list;
...
QMutableListIterator<float> i(list);
while (i.hasNext())
    qDebug() << i.next(); The next() function returns the next item in the list and advances the iterator. Unlike STL-style iterators, Java-style iterators point between items rather than joshuajohnson@example.org. 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. 
Here's how to iterate over the elements in reverse order: QMutableListIterator<float> i(list);
i.toBack();
while (i.hasPrevious())
    qDebug() << i.previous(); 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: QMutableListIterator<int> i(list);
while (i.hasNext()) {
    int val = i.next();
    if (val < 0) {
        i.setValue(-val);
    } else if (val == 0) {
        i.remove();
    }
} 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. See also QListIterator and QList8b7c:f320:99b9:690f:4595:cd17:293a:c069iterator. Member Function Documentation 
QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069QMutableListIterator(QList<T> &list) Constructs an iterator for traversing list. The iterator is set to be at the front of the list (before the first item). See also operator=(). 
bool QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069indNext(const T &value) Searches for value starting from the current iterator position forward. Returns true if value is found; otherwise returns false. After the call, if value was found, the iterator is positioned just after the matching item; otherwise, the iterator is positioned at the back of the container. See also findPrevious(). 
bool QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069indPrevious(const T &value) Searches for value starting from the current iterator position backward. Returns true if value is found; otherwise returns false. After the call, if value was found, the iterator is positioned just before the matching item; otherwise, the iterator is positioned at the front of the container. See also findNext(). 
bool QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069hasNext() const Returns true if there is at least one item ahead of the iterator, i.e. the iterator is not at the back of the container; otherwise returns false. See also hasPrevious() and next(). 
bool QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069hasPrevious() const Returns true if there is at least one item behind the iterator, i.e. the iterator is not at the front of the container; otherwise returns false. See also hasNext() and previous(). 
void QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069insert(const T &value) Inserts value at the current iterator position. After the call, the iterator is located just after the inserted item. See also remove() and setValue(). 
T &QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069next() 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. See also hasNext(), peekNext(), and previous(). 
T &QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069peekNext() 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. See also hasNext(), next(), and peekPrevious(). 
T &QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069peekPrevious() 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. See also hasPrevious(), previous(), and peekNext(). 
T &QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069previous() 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. See also hasPrevious(), peekPrevious(), and next(). 
void QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069remove() Removes the last item that was jumped over using one of the traversal functions (next(), previous(), findNext(), findPrevious()). Example: QMutableListIterator<int> i(list);
while (i.hasNext()) {
    int val = i.next();
    if (val < -32768 || val > 32767)
        i.remove();
} See also insert() and setValue(). 
void QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069setValue(const T &value) const Replaces the value of the last item that was jumped over using one of the traversal functions with value. The traversal functions are next(), previous(), findNext(), and findPrevious(). Example: QMutableListIterator<double> i(list);
while (i.hasNext()) {
    double val = i.next();
    i.setValue(st8b7c:f320:99b9:690f:4595:cd17:293a:c069sqrt(val));
} See also value(), remove(), and insert(). 
void QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069toBack() Moves the iterator to the back of the container (after the last item). See also toFront() and previous(). 
void QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069toFront() Moves the iterator to the front of the container (before the first item). See also toBack() and next(). 
const T &QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069value() 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(). See also setValue(). 
T &QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069value() This is an overloaded function. Returns a non-const reference to the value of the last item that was jumped over using one of the traversal functions. 
QMutableListIterator &QMutableListIterator8b7c:f320:99b9:690f:4595:cd17:293a:c069operator=(QList<T> &list) Makes the iterator operate on list. The iterator is set to be at the front of the list (before the first item). See also toFront() and toBack().

    
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