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/Qt 5.11

QDBusVariant Class

The QDBusVariant class enables the programmer to identify the variant type provided by the D-Bus typesystem. More...

Header: #include <QDBusVariant>
qmake: QT += dbus
Since: Qt 4.2

Public Functions

QDBusVariant()
QDBusVariant(const QVariant &variant)
QDBusVariant(QVariant &&v)
void setVariant(const QVariant &variant)
void swap(QDBusVariant &other)
QVariant variant() const

Detailed Description

The QDBusVariant class enables the programmer to identify the variant type provided by the D-Bus typesystem.

A D-Bus function that takes an integer, a D-Bus variant and a string as parameters can be called with the following argument list (see QDBusMessage::setArguments()):

    QList<QVariant> arguments;
    arguments << QVariant(42) << QVariant::fromValue(QDBusVariant(43)) << QVariant("hello");
    myDBusMessage.setArguments(arguments);

When a D-Bus function returns a D-Bus variant, it can be retrieved as follows:

    // call a D-Bus function that returns a D-Bus variant
    QVariant v = callMyDBusFunction();
    // retrieve the D-Bus variant
    QDBusVariant dbusVariant = qvariant_cast<QDBusVariant>(v);
    // retrieve the actual value stored in the D-Bus variant
    QVariant result = dbusVariant.variant();

The QVariant within a QDBusVariant is required to distinguish between a normal D-Bus value and a value within a D-Bus variant.

See also The Qt D-Bus Type System.

Member Function Documentation

QDBusVariant::QDBusVariant()

Constructs a new D-Bus variant.

QDBusVariant::QDBusVariant(const QVariant &variant)

Constructs a new D-Bus variant from the given Qt variant.

See also setVariant().

QDBusVariant::QDBusVariant(QVariant &&v)

Default constructs an instance of QDBusVariant.

void QDBusVariant::setVariant(const QVariant &variant)

Assigns the value of the given Qt variant to this D-Bus variant.

See also variant().

void QDBusVariant::swap(QDBusVariant &other)

Swaps this QDBusVariant instance with other.

QVariant QDBusVariant::variant() const

Returns this D-Bus variant as a QVariant object.

See also setVariant().

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Licensed under the GNU Free Documentation License, Version 1.3.
https://doc.qt.io/qt-5/qdbusvariant.html