doc_src_qiterator.cpp

Go to the documentation of this file.

// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include <QList>
#include <QSet>
 
void example()
{
    {
        //! [0]
        QList<float> list;
        //...
        QListIterator<float> i(list);
        while (i.hasNext())
            float f = i.next();
        //! [0]
    }
 
    QList<float> list;
 
    {
        //! [1]
        QListIterator<float> i(list);
        i.toBack();
        while (i.hasPrevious())
            float f = i.previous();
        //! [1]
    }
 
    {
        //! [6]
        QSet<QString> set;
        //...
        QSetIterator<QString> i(set);
        while (i.hasNext())
            QString f = i.next();
        //! [6]
    }
 
    {
        //! [8]
        QList<float> list;
        //...
        QMutableListIterator<float> i(list);
        while (i.hasNext())
            float f = i.next();
        //! [8]
    }
 
    {
        //! [9]
        QMutableListIterator<float> i(list);
        i.toBack();
        while (i.hasPrevious())
            float f = i.previous();
        //! [9]
    }
 
    {
        QList<int> list = {1, 2, 3, 4, 5};
        //! [10]
        QMutableListIterator<int> i(list);
        while (i.hasNext()) {
            int val = i.next();
            if (val < 0) {
                i.setValue(-val);
            } else if (val == 0) {
                i.remove();
            }
        }
        //! [10]
    }
 
    {
        //! [17]
        QSet<float> set;
        //...
        QMutableSetIterator<float> i(set);
        while (i.hasNext())
            float f = i.next();
        //! [17]
    }
 
    {
        QList<int> list = {1, 2, 3, 4, 5};
        //! [19]
        QMutableListIterator<int> i(list);
        while (i.hasNext()) {
            int val = i.next();
            if (val < -32768 || val > 32767)
                i.remove();
        }
        //! [19]
    }
 
    {
        QSet<int> set;
        //! [22]
        QMutableSetIterator<int> i(set);
        while (i.hasNext()) {
            int val = i.next();
            if (val < -32768 || val > 32767)
                i.remove();
        }
        //! [22]
    }
 
    {
        QList<double> list;
        //! [23]
        QMutableListIterator<double> i(list);
        while (i.hasNext()) {
            double val = i.next();
            i.setValue(std::sqrt(val));
        }
        //! [23]
    }
 
    {
        //! [25]
        QList<int> list;
        //...
        QListIterator<int> i(list);
        while (i.hasNext())
            int val = i.next();
        //! [25]
    }
}
 
#if  __has_include(<QWidget>)
#include <QWidget>
void example_widgets()
{
    QMap<int, QWidget *> map;
    {
        //! [26]
        QMap<int, QWidget *> map;
        //...
        QMapIterator<int, QWidget *> i(map);
        while (i.hasNext()) {
            i.next();
            qDebug() << i.key() << ": " << i.value();
        }
        //! [26]
    }
 
    {
        //! [27]
        QMapIterator<int, QWidget *> i(map);
        i.toBack();
        while (i.hasPrevious()) {
            i.previous();
            qDebug() << i.key() << ": " << i.value();
        }
        //! [27]
    }
 
    QWidget *widget;
    {
        //! [28]
        QMapIterator<int, QWidget *> i(map);
        while (i.findNext(widget)) {
            qDebug() << "Found widget " << widget << " under key "
                    << i.key();
        }
        //! [28]
    }
 
    {
        //! [26multi]
        QMultiMap<int, QWidget *> multimap;
        //...
        QMultiMapIterator<int, QWidget *> i(multimap);
        while (i.hasNext()) {
            i.next();
            qDebug() << i.key() << ": " << i.value();
        }
        //! [26multi]
    }
 
    QMultiMap<int, QWidget *> multimap;
    {
        //! [27multi]
        QMultiMapIterator<int, QWidget *> i(multimap);
        i.toBack();
        while (i.hasPrevious()) {
            i.previous();
            qDebug() << i.key() << ": " << i.value();
        }
        //! [27multi]
    }
 
    {
        //! [28multi]
        QMultiMapIterator<int, QWidget *> i(multimap);
        while (i.findNext(widget)) {
            qDebug() << "Found widget " << widget << " under key "
                    << i.key();
        }
        //! [28multi]
    }
 
    {
        //! [29]
        QHash<int, QWidget *> hash;
        //...
        QHashIterator<int, QWidget *> i(hash);
        while (i.hasNext()) {
            i.next();
            qDebug() << i.key() << ": " << i.value();
        }
        //! [29]
    }
 
    QHash<int, QWidget *> hash;
    {
        //! [31]
        QHashIterator<int, QWidget *> i(hash);
        while (i.findNext(widget)) {
            qDebug() << "Found widget " << widget << " under key "
                    << i.key();
        }
        //! [31]
    }
 
    {
        //! [32]
        QMap<int, QWidget *> map;
        //...
        QMutableMapIterator<int, QWidget *> i(map);
        while (i.hasNext()) {
            i.next();
            qDebug() << i.key() << ": " << i.value();
        }
        //! [32]
    }
 
    {
        //! [33]
        QMutableMapIterator<int, QWidget *> i(map);
        i.toBack();
        while (i.hasPrevious()) {
            i.previous();
            qDebug() << i.key() << ": " << i.value();
        }
        //! [33]
    }
 
    {
        //! [34]
        QMutableMapIterator<int, QWidget *> i(map);
        while (i.findNext(widget)) {
            qDebug() << "Found widget " << widget << " under key "
                    << i.key();
        }
        //! [34]
    }
 
    {
        QMap<QString, QString> map;
        //! [35]
        QMutableMapIterator<QString, QString> i(map);
        while (i.hasNext()) {
            i.next();
            if (i.key() == i.value())
                i.remove();
        }
        //! [35]
    }
 
    {
        //! [32multi]
        QMultiMap<int, QWidget *> multimap;
        //...
        QMutableMultiMapIterator<int, QWidget *> i(multimap);
        while (i.hasNext()) {
            i.next();
            qDebug() << i.key() << ": " << i.value();
        }
        //! [32multi]
    }
 
    {
        //! [33multi]
        QMutableMultiMapIterator<int, QWidget *> i(multimap);
        i.toBack();
        while (i.hasPrevious()) {
            i.previous();
            qDebug() << i.key() << ": " << i.value();
        }
        //! [33multi]
    }
 
    {
        //! [34multi]
        QMutableMultiMapIterator<int, QWidget *> i(multimap);
        while (i.findNext(widget)) {
            qDebug() << "Found widget " << widget << " under key "
                    << i.key();
        }
        //! [34multi]
    }
 
    {
        QMultiMap<QString, QString> multimap;
        //! [35multi]
        QMutableMultiMapIterator<QString, QString> i(multimap);
        while (i.hasNext()) {
            i.next();
            if (i.key() == i.value())
                i.remove();
        }
        //! [35multi]
    }
 
    {
        //! [36]
        QHash<int, QWidget *> hash;
        //...
        QMutableHashIterator<int, QWidget *> i(hash);
        while (i.hasNext()) {
            i.next();
            qDebug() << i.key() << ": " << i.value();
        }
        //! [36]
    }
 
    {
        //! [38]
        QMutableHashIterator<int, QWidget *> i(hash);
        while (i.findNext(widget)) {
            qDebug() << "Found widget " << widget << " under key "
                    << i.key();
        }
        //! [38]
    }
 
    {
        QHash<QString, QString> hash;
        //! [39]
        QMutableHashIterator<QString, QString> i(hash);
        while (i.hasNext()) {
            i.next();
            if (i.key() == i.value())
                i.remove();
        }
        //! [39]
    }
}
#endif