How to pass and modify Javascript object in C++?

daljit97

So I have the following code:

    Item{
        id: item
        property variant dataMap
        
        signal fired()
        
        onFired:{
            qmlHelper.getData(dataMap)
console.debug(dataMap[0];
        }
    }

In C++ I have:

void QmlHelper::getProfile(here I want my dataMap)
{
    QUrl url (BASE_URL);
    QNetworkRequest request(url);
    QNetworkReply* reply = networkManager->get();
    connect(reply,SIGNAL(finished()),this, SLOT(onDataRetrieved()));
}


void QmlHelper::onDataRetrieved()
{
    QNetworkReply * reply = qobject_cast<QNetworkReply *>(sender());

    if(reply->error() == QNetworkReply::NoError)
    {
// modify my dataMap here 
    }
    reply->deleteLater();
}

raven-worx

@daljit97
Create a QProperty with at least a getter (READ) and changed-signal (NOTIFY)
Then you should be able to use QML's property binding.

Alternatively you can connect similiar like you would do in C++:

Component.onCompleted: {
        qmlHelper.mySignal.connect(onFired)
}

    function onFired(param) {
        ...
    }

Both approaches need a signal in your C++ class

daljit97

The problem is I need to create a new dataMap on the go since I use multiple Qml Pages, if I connect a signal from C++ it would be connected to all of my items.

raven-worx

@daljit97
how did you register qmlHelper to the qml engine?
If you did it with qmlRegisterType then each item can instantiate it's own local member of this type. So you only have a 1:1 relation.

daljit97

QmlHelper is a class made available to qml using

QDeclarativeContext::setContextProperty(const QString & name, QObject * value)

Is using qmlRegisterType the only solution? I'd prefer to avoid as that would create other problems to solve in my project.