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const_iterator Class

(QSequentialIterable::const_iterator)

The QSequentialIterable::const_iterator allows iteration over a container in a QVariant. More...

Header: #include <const_iterator>
qmake: QT += core
Since: Qt 5.2

Public Functions

const_iterator(const const_iterator & other)
~const_iterator()
bool operator!=(const const_iterator & other) const
const QVariant operator*() const
const_iterator operator+(int j) const
const_iterator & operator++()
const_iterator operator++(int)
const_iterator & operator+=(int j)
const_iterator operator-(int j) const
const_iterator & operator--()
const_iterator operator--(int)
const_iterator & operator-=(int j)
const_iterator & operator=(const const_iterator & other)
bool operator==(const const_iterator & other) const

Detailed Description

The QSequentialIterable::const_iterator allows iteration over a container in a QVariant.

A QSequentialIterable::const_iterator can only be created by a QSequentialIterable instance, and can be used in a way similar to other stl-style iterators.

QList<int> intList;
intList.push_back(7);
intList.push_back(11);
intList.push_back(42);

QVariant variant = QVariant::fromValue(intList);
if (variant.canConvert<QVariantList>()) {
    QSequentialIterable iterable = variant.value<QSequentialIterable>();
    // Can use foreach:
    foreach (const QVariant &v, iterable) {
        qDebug() << v;
    }
    // Can use C++11 range-for:
    for (const QVariant &v : iterable) {
        qDebug() << v;
    }
    // Can use iterators:
    QSequentialIterable::const_iterator it = iterable.begin();
    const QSequentialIterable::const_iterator end = iterable.end();
    for ( ; it != end; ++it) {
        qDebug() << *it;
    }
}

See also QSequentialIterable.

Member Function Documentation

const_iterator::​const_iterator(const const_iterator & other)

Creates a copy of other.

const_iterator::​~const_iterator()

Destroys the QSequentialIterable::const_iterator.

bool const_iterator::​operator!=(const const_iterator & other) const

Returns true if other points to a different item than this iterator; otherwise returns false.

See also operator==().

const QVariant const_iterator::​operator*() const

Returns the current item, converted to a QVariant.

const_iterator const_iterator::​operator+(int j) const

Returns an iterator to the item at j positions forward from this iterator.

See also operator-() and operator+=().

const_iterator & const_iterator::​operator++()

The prefix ++ operator (++it) advances the iterator to the next item in the container and returns an iterator to the new current item.

Calling this function on QSequentialIterable::end() leads to undefined results.

See also operator--().

const_iterator const_iterator::​operator++(int)

This is an overloaded function.

The postfix ++ operator (it++) advances the iterator to the next item in the container and returns an iterator to the previously current item.

const_iterator & const_iterator::​operator+=(int j)

Advances the iterator by j items.

See also operator-=() and operator+().

const_iterator const_iterator::​operator-(int j) const

Returns an iterator to the item at j positions backward from this iterator.

If the container in the QVariant does not support bi-directional iteration, calling this function leads to undefined results.

See also operator+(), operator-=(), and canReverseIterate().

const_iterator & const_iterator::​operator--()

The prefix -- operator (--it) makes the preceding item current and returns an iterator to the new current item.

Calling this function on QSequentialIterable::begin() leads to undefined results.

If the container in the QVariant does not support bi-directional iteration, calling this function leads to undefined results.

See also operator++() and canReverseIterate().

const_iterator const_iterator::​operator--(int)

This is an overloaded function.

The postfix -- operator (it--) makes the preceding item current and returns an iterator to the previously current item.

If the container in the QVariant does not support bi-directional iteration, calling this function leads to undefined results.

See also canReverseIterate().

const_iterator & const_iterator::​operator-=(int j)

Makes the iterator go back by j items.

If the container in the QVariant does not support bi-directional iteration, calling this function leads to undefined results.

See also operator+=(), operator-(), and canReverseIterate().

const_iterator & const_iterator::​operator=(const const_iterator & other)

Assigns other to this.

bool const_iterator::​operator==(const const_iterator & other) const

Returns true if other points to the same item as this iterator; otherwise returns false.

See also operator!=().

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