[SOLVED] accessing parameter (with non-basic type) of C++ signal

morte

Assume we have C++ object of type QGeoSatelliteInfoSource registered as context property
which emits signal
void satellitesInUseUpdated(const QList<QGeoSatelliteInfo> & satellites),

QML-side handle that signal at Connections { onSatellitesInUseUpdated: {...} } ,
how to use satellites parameter of type QVariant(QList<QGeoSatelliteInfo>) ?

p3c0

Hi,

AFAIK it should be accessible just like accessing a JavaScript array.
For eg:
In C++
@
QVariantList list;
list << "Data1" << "Data2" << "Data1";
...
emit listData(list);
@

and then from QML
@
onListData: {
console.log(list)
console.log(list[0],list[1])
}
@

morte

Here test output:

@ console.log("typeof satellites", typeof satellites);
console.log("satellites", satellites);
console.log("satellites.size", satellites.size);
console.log("satellites.size()", satellites.size);
console.log("satellites[0]", satellites[0]);
@

@qml: typeof satellites object
qml: satellites QVariant(QList<QGeoSatelliteInfo>)
qml: satellites.size undefined
qml: satellites.size() undefined
qml: satellites[0] undefined
@

Rolias

Have you registered the C++ QGeoSatelliteInfo as a known type to QML? If you have and QList<QGeoSatelliteInfo> doesn't work you could try making it a QVariantList on the C++ side. The "data conversion docs":http://qt-project.org/doc/qt-5/qtqml-cppintegration-data.html make me think this would work, whereas they aren't specific about QList<T> except for basic types for T.

morte

Thanks for replies. No, QGeoSatelliteInfo is not registered because i wanted just to get size of the list. I have read in docs that List<T> where T is non-basic type cant be used for transfer sequences to QML and QList isn't QObject derived class. QQmlListProperty<> should be used for that purpose. So anyway making an new 'proxy' class at C++ side is needed.