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/*!
\page positioning-cpp-qml.html
\title Interfaces between C++ and QML Code in Qt Positioning

\brief Some of the providing QtPositioning QML types providing interfaces to access and modify properties in C++.

\section1 Overview

Depending on the type of C++ class QtPositioning utilizes two methods to simplify
exchange of position data between C++ and QML code.

\target Cpp_value_integration_positioning
\section1 Direct C++ Value Integration in QtPositioning

Starting with Qt 5.5, it has become much easier to integrate non-QObject based
data types into QML. This is achieved by adding \l Q_GADGET support to QtQml.
The macro converts classes into a light-weight
version of a QObject without the required \l QObject inheritance. At the same time
it retains the reflection capabilities of \l QMetaObject. As a result they can be directly
exposed to QML and do not require any further wrapper classes.

A significant number of Position and Location
related data types were converted to Q_GADGETs. They retain their API and value
type character but have become introspectable via \l QMetaObject. This conversion
was done to the following classes:

\list
\li \l QGeoCircle
\li \l QGeoCoordinate
\li \l QGeoRectangle
\li \l QGeoShape
\endlist

Using \l QGeoCoordinate as an example, the C++ types are directly exposed to the
QML environment via its meta type:

\code
    qRegisterMetaType<QGeoCoordinate>();
    QMetaType::registerEqualsComparator<QGeoCoordinate>();
\endcode

The above registration of \l QGeoCoordinate is automatically done once by the
QtPositioning QML plugin. The \l{Plane Spotter (QML)}{Plane Spotter} example demonstrates
this feature.

\section1 QVariant Based integration

This section provides information on how to integrate QGeoAddress and QGeoLocation.

\section2 Address - QGeoAddress
The \l {QtPositioning::Address::address} {Address.address} property is used to provide an interface between C++ and QML code.  First a pointer to a
Address object must be obtained from C++, then use the \l {QObject::property()}{property()} and
\l {QObject::setProperty()}{setProperty()} functions to get and set the \c address property.
The following gets the QGeoAddress representing this object from C++:
\snippet cpp/cppqml.cpp Address get
The following sets the properties of this object based on a QGeoAddress object from C++:
\snippet cpp/cppqml.cpp Address set


\section2 Location - QGeoLocation
The \l {Location::location} {Location.location} property is used to provide an interface between C++ and QML code.  First a pointer to a
Location object must be obtained from C++, then use the \l {QObject::property()}{property()} and
\l {QObject::setProperty()}{setProperty()} functions to get and set the \c location property.
The following gets the QGeoLocation representing this object from C++:
\snippet cpp/cppqml.cpp Location get
The following sets the properties of this object based on a QGeoLocation object from C++:
\snippet cpp/cppqml.cpp Location set

*/
