W3cubDocs

/Qt

QDBusVariant Class

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

Header: #include <QDBusVariant>
CMake: find_package(Qt6 COMPONENTS Dbus REQUIRED) target_link_libraries(mytarget PRIVATE Qt6::Dbus)
qmake: QT += dbus

Public Functions

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

Detailed Description

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(const QVariant &variant)

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

See also setVariant().

QDBusVariant::QDBusVariant()

Constructs a new D-Bus variant.

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().

© The Qt Company Ltd
Licensed under the GNU Free Documentation License, Version 1.3.
https://doc.qt.io/qt-6.2/qdbusvariant.html