QNetworkManager : resend qnetworkrequest before end make it crash

[MrDiv]

Hey,

I'm working on an embedded buying application. When the customer add a product to his cart, i send a QNetworkRequest with a webservice as URL to update the backoffice. But if the customer double click the add-to-cart button, i think that the request is resend before the end of the first and make the application exit with error : "QEventLoop::exec: instance 0x423190 has already called exec()".

Here is my doRequest function :

const QString&                            Request::doRequest(const QString& request, RequestType type, const QByteArray& data)
{
    QObject::connect(&_networkManager, SIGNAL(finished(QNetworkReply*)), &_eventLoop, SLOT(quit()));
    QUrl url(request);
    QNetworkRequest req(url);

    switch (type)
    {
    case e_GET :
        _reply = _networkManager.get(req);
        break;
    case e_POST :
        _reply = _networkManager.post(req, data);
        break;
    case e_PUT :
        _reply = _networkManager.put(req, data);
        break;
    case e_DELETE :
        _reply = _networkManager.deleteResource(req);
        break;
    }
    _eventLoop.exec();
    if (_reply->error() == QNetworkReply::NoError)
        {
            QString result = _reply->readAll();
            delete _reply;
            return (result);
        }
    delete _reply;
    return ("");
}

Does anyone encounter the same problem ? Is there a work around?

[MrDiv]

One possible solution is to launch one thread for each request

[SGaist]

Hi and welcome to devnet,

That's because you are calling exec on _eventLoop twice. You should rather use a local QEventLoop or not allow the query to start if already in progress.