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qt4qmlqt-quick

Accessing properties of QML objects from C++ withoun Q_PROPERTY definition


I know, it's possible to define a QObject with custom properties and expose this object in QML environment. But this way, for each new property I'd need to recompile C++ code.

Is it possible, to make a dynamic binding from C++/Qt to QML-objects? Something like:

//C++ code: 
updateProperty("myQmlObject.any_property", "Hello World");

Thank you!

SOLVED:

_view->rootContext()->setContextProperty( "cppmessage" , "Hello from C++" );

WHERE: view is a QDeclarativeView, and cppmessage is used in QML without prior declaration like: "text: cppmessage"

This link was usefull for finding the solution: http://xizhizhu.blogspot.com/2010/10/hybrid-application-using-qml-and-qt-c.html


Solution

  • Yes, This can be done. Link

    // MyItem.qml
    import QtQuick 1.0
    
    Item {
        property int someNumber: 100
    }
    
    //C++
    QDeclarativeEngine engine;
    QDeclarativeComponent component(&engine, "MyItem.qml");
    QObject *object = component.create();
    
    qDebug() << "Property value:" << QDeclarativeProperty::read(object,"someNumber").toInt();
    QDeclarativeProperty::write(object, "someNumber", 5000);
    
    qDebug() << "Property value:" << object->property("someNumber").toInt();
    object->setProperty("someNumber", 100);
    

    Edit:1 Another way to do it , as suggested by @Valentin is listed here link