QT return value from a signal

AMOL

Hello developers,
Need urgent help to solve one issue.
I am creating client app which will connect to server, this server is Qwebsocket server.
So when I connected I am sending data and receiving message in return .
Now issue is when after connecting As per example I sued signals to connect and receive message.
So how can we get that message in return from signal
I am posting my function code here,

bool plsqlserver::run(QString data)
{

getData=data;
QUrl url=QStringLiteral("wss://localhost:2443");
connect(&my_webSocket, &QWebSocket::connected,[this](){
    my_webSocket.sendTextMessage(getData);
    connect(&my_webSocket, &QWebSocket::textMessageReceived,
            [this](QString message){
        setReturnva(appendString(message));
        qDebug()<< "run returnvalue" << returnvalue; //*here my value appeard I want this value in return or atleast to use in this function*//

        }

        my_webSocket.close();
        my_webSocket.abort();
        my_webSocket.disconnect();

    });

});


connect(&my_webSocket, QOverload<const QList<QSslError>&>::of(&QWebSocket::sslErrors),
        this, &plsqlserver::onSslErrors);
qDebug()<<&my_webSocket;
my_webSocket.open(QUrl(url));

return returnvalue; <-----here no value is getting in return

}

Please help me , thanks in advance

SGaist

Hi,

Signals have no return value.

All your code is asynchronous so use that paradigm as well for the rest. Emit a signal once you've go the data you requested to propagate it further.

AMOL

Hi @SGaist, I tried to emit signal at which set value in another function but and try get that value but before I get the value my function is completed and I got nothing in return
Can you help me how to get that returnvalue value in my code at the end to return?

AMOL

Also I found somthing in which he is getting message out side of signal, but I am not able to do the same for my case
QJsonObject Schedule::getImageWithInfo()
{
QString response;
QString* responsePtr = &response;

QWebSocket websocket;
QWebSocket* websocketPtr = &websocket;

QObject::connect(websocketPtr, &QWebSocket::connected, [&, websocketPtr, responsePtr]()
{
    qInfo() << "Schedule::getImageWithInfo: Connected";
    QObject::connect(websocketPtr, &QWebSocket::textMessageReceived, [websocketPtr, responsePtr](const QString& msg)
    {
        qInfo() << "Schedule::getImageWithInfo: message received";
        *responsePtr = msg;
        websocketPtr->close();
    });

    QJsonObject command;
    command.insert("command", "GET_IMAGES_WITH_INFO");
    QJsonDocument doc(command);
    QString strJson(doc.toJson(QJsonDocument::Compact));
    qInfo() << "Schedule::getImageWithInfo: Sending command " << strJson;

    websocketPtr->sendTextMessage(strJson);
});

websocket.open(QUrl(urlStr));

QEventLoop eventLoop;
QObject::connect(&websocket, SIGNAL(disconnected()), &eventLoop, SLOT(quit()));
eventLoop.exec();

QJsonObject responseObj = Utils::QJsonObjectFromString(response);
return responseObj;

}

Can you check this and let me know how I can use this same for my case
Instead of jason object I want to use plain messgae

AMOL

Somehow I managed to get value using single and made logic to send it to qml
So issue is resolved
Thank you for helping.....