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Diffstat (limited to 'src/positioning/doc/src/cpp-qml-positioning.qdoc')
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diff --git a/src/positioning/doc/src/cpp-qml-positioning.qdoc b/src/positioning/doc/src/cpp-qml-positioning.qdoc index 77ada78a..9245c171 100644 --- a/src/positioning/doc/src/cpp-qml-positioning.qdoc +++ b/src/positioning/doc/src/cpp-qml-positioning.qdoc @@ -31,6 +31,49 @@ \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 |