Next Noobie question...on C++ / QML integration

SPlatten

I have a C++ object that corresponds to an instance of a QML file. I have properties in the C++ class:

    Q_PROPERTY(bool canBeStale READ canBeStale WRITE setCanBeStale)
    Q_PROPERTY(double* dataLink READ pDataLink WRITE setDataLink)
    Q_PROPERTY(QString dataTag READ strUDT WRITE setUDT)
    Q_PROPERTY(double value READ getValue WRITE setValue NOTIFY dataUpdate)

And similar properties in the QML:

    id: root
    readonly property alias api           : datahlpr
    property bool canbeStale              : false
    property var dataLink
    property var dataTag

Is there a way to map the QML and C++ properties as presently I have added to the QML:

    Component.onCompleted: {
    //Set-up mappings to C++ object
        api.dataTag = root.dataTag
        api.dataTag = root.dataTag
        api.canBeStale = root.canbeStale
    }

Bob64

@SPlatten I am not sure what you mean by the "corresponding" QML file here. The C++ defines an object that is instantiable in QML directly which already has the properties exposed and so on. When you instantiate it, you will assign the properties with values from your QML environment.

So for example, say you have exposed MyComponent from C++ with the properties you mentioned.

Then in some QML component that uses this you will have (e.g.):

MyClientComponent.qml

Item {
    ...
    MyComponent {
        id: mycomp
        canbeStale: true
        dataTag: "bob"
        ...

You can bind to and from the MyComponent properties in the client QML component in the usual way.

SPlatten

@Bob64 , what I was really asking for was is there a way to auto assign properties of the same name in the QML object to the C++ equivalent object ?

Bob64

@SPlatten I think the issue that I still don't understand what you mean by "equivalent" object. Can you give a minimal example that shows more of the structure of your real system? The code in your original post just showed properties so it was difficult to see what components/classes were involved and how they related to each other.

JoeCFD

Does binding help? Check the small example here.
https://stackoverflow.com/questions/41232999/two-way-binding-c-model-in-qml

SPlatten

@JoeCFD , yes, it would, however, the main reason I was asking was if there was already a very simple and transparent method of doing the same.

lemons

Maybe my simple example I posted earlier this year helps you:
https://forum.qt.io/topic/135077/creating-a-c-identifier-for-a-dynamically-generated-object/2