c++jsonqtqwebviewqjsonobject

How send a QJsonObject using QWebChannel in Qt

Im implementing a HTML wrapper in Qt using QWebChannel, and im sucessifully able to send string, but, i woud like to send a QJsonObject, Not a json string like "{a:1,b:2}" but a Qt QJsonObject. Is it possible?

the official documentation says

"No manual message passing and serialization of data is required," http://doc.qt.io/qt-5/qwebchannel.html

How can I emit a signal with a JsonObject instead of a string?

This is my QWebChannel connected class

class Mapa : public QObject{
    Q_OBJECT

    public:
        explicit Mapa();
        displayMessage(const QString &message);
    signals:
        updateText(const QString &text); // success :sends text
        updateJson( const QJsonObject   &json); // fail: sends null
        updateJsond(const QJsonDocument &jsondoc);// fail: sends null
    }
 }

and here is my main code

Mapa map;
// setup the channel
QWebChannel channel;
QObject::connect(&clientWrapper, &WebSocketClientWrapper::clientConnected, &channel, &QWebChannel::connectTo);

// setup the dialog and publish it to the QWebChannel
channel.registerObject(QStringLiteral("map"), &map);

map.updateText("text");// sends "text" string

QJsonObject j;
j["Altitude"]  = 10;

map.updateJson(j); // sends "null" string
QJsonDocument doc(j);
map.updateJsond(doc); // sends "null" string
Solution

  • Instead of using the QJson family objects, you can send QVariant objects to your Javascript code

    You can use the .toVariantMap() and .toVariantList() methods easily to convert your objects from the JSON objects.