Qt Documentation

Qt 5.14
Qt D-Bus
C++ Classes
QDBusVariant

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

This class was introduced in Qt 4.2.

List of all members, including inherited members

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.