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QSequentialIterable Class

The QSequentialIterable class is an iterable interface for a container in a QVariant. More...

Header: #include <QSequentialIterable>
CMake: find_package(Qt6 REQUIRED COMPONENTS Core)
target_link_libraries(mytarget PRIVATE Qt6::Core)
qmake: QT += core
Inherits: QIterable

Public Types

BidirectionalConstIterator
BidirectionalIterator
ForwardConstIterator
ForwardIterator
InputConstIterator
InputIterator
RandomAccessConstIterator
RandomAccessIterator
const_iterator
(since 6.0) iterator

Public Functions

void addValue(const QVariant &value, QSequentialIterable::Position position = Unspecified)
QVariant at(qsizetype idx) const
void removeValue(QSequentialIterable::Position position = Unspecified)
void set(qsizetype idx, const QVariant &value)

Detailed Description

This class allows several methods of accessing the values of a container held within a QVariant. An instance of QSequentialIterable can be extracted from a QVariant if it can be converted to a QVariantList.

QList<int> intList = {7, 11, 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;
    }
}

The container itself is not copied before iterating over it.

See also QVariant.

Member Type Documentation

[alias] QSequentialIterable::BidirectionalConstIterator

Exposes a const_iterator using std::bidirectional_iterator_tag.

[alias] QSequentialIterable::BidirectionalIterator

Exposes an iterator using std::bidirectional_iterator_tag.

[alias] QSequentialIterable::ForwardConstIterator

Exposes a const_iterator using std::forward_iterator_tag.

[alias] QSequentialIterable::ForwardIterator

Exposes an iterator using std::forward_iterator_tag.

[alias] QSequentialIterable::InputConstIterator

Exposes a const_iterator using std::input_iterator_tag.

[alias] QSequentialIterable::InputIterator

Exposes an iterator using std::input_iterator_tag.

[alias] QSequentialIterable::RandomAccessConstIterator

Exposes a const_iterator using std::random_access_iterator_tag.

[alias] QSequentialIterable::RandomAccessIterator

Exposes an iterator using std::random_access_iterator_tag.

[alias] QSequentialIterable::const_iterator

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 = {7, 11, 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;
    }
}

[alias, since 6.0] QSequentialIterable::iterator

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

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

This typedef was introduced in Qt 6.0.

Member Function Documentation

void QSequentialIterable::addValue(const QVariant &value, QSequentialIterable::Position position = Unspecified)

Adds value to the container, at position, if possible.

QVariant QSequentialIterable::at(qsizetype idx) const

Returns the value at position idx in the container.

void QSequentialIterable::removeValue(QSequentialIterable::Position position = Unspecified)

Removes a value from the container, at position, if possible.

void QSequentialIterable::set(qsizetype idx, const QVariant &value)

Sets the element at position idx in the container to value.

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