QNetworkAccessManager doesn't send signals

thecatishere

When I call fromGoogle it never goes to the finished slot.
Both connects return true, I've tried capturing QNetworkReply::readyRead and finished, they don't go to the slot either. I don't know if the signal is being send or not, I only know that it's not going in the connected slot.
My question is why is the signal not being received in the slots?
This is Qt 6.1.3

networkmanager.cpp

NetworkManager::NetworkManager(IAnswerer* answerer)
{
    manager = new QNetworkAccessManager();
    connect(manager, &QNetworkAccessManager::finished,
            this, &NetworkManager::finished);

    connect(this, &NetworkManager::parsed,
            answerer, &IAnswerer::networkAnswer);
}

NetworkManager::~NetworkManager()
{
    delete manager;
}

int NetworkManager::fromGoogle(QByteArray question)
{
    manager->get(QNetworkRequest(QUrl(question)));
    return 0;
}

void NetworkManager::finished(QNetworkReply *reply)
{
    qDebug() << "finished";
    emit parsed(reply->readAll().mid(50, 20));
}

networkmanager.h

class NetworkManager : public QObject
{
    Q_OBJECT
private:
    QNetworkAccessManager *manager;
public:
    explicit NetworkManager(IAnswerer * answerer);
    ~NetworkManager();
    int fromGoogle(QByteArray question);
public slots:
    void finished(QNetworkReply *reply);
signals:
    void parsed(QByteArray answer);
};

answerer.h

class Answerer : IAnswerer
{
    NetworkManager netManager;
...
public:
    Answerer(QSettings &settings);
...
public slots:
    void networkAnswer(QByteArray answer);

Constructor in the source file:

Answerer::Answerer(QSettings &_settings)
    : settings(_settings), netManager(this) { ... }

ianswerer.h

class IAnswerer : public QObject
{
    Q_OBJECT
public slots:
    virtual void networkAnswer(QByteArray answer) = 0;
};

SGaist

Hi and welcome to devnet,

You should also connect the error related signals in case something goes wrong.

thecatishere

@SGaist , I forgot the mention that I already did that as well, and they didn't receive anything also.

Christian Ehrlicher

@thecatishere said in QNetworkAccessManager doesn't send signals:

Answerer

How / where do you instantiate it?

And creating a new QNetworkManager for every request is not good at all.

thecatishere

@Christian-Ehrlicher The manager is created in the constructor of NetworkManager, which is a single object instantiated in the constructor of Answerer. Answerer is again a single object that doesn't get deleted throughout the whole program runtime.
reader.h

class Reader
{
    Answerer answerer;
...

reader.cpp

Reader::Reader()
    : answerer(settings) { ... }

main.cpp

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    Reader reader;

    return a.exec();
}

Christian Ehrlicher

Maybe you should try with a simple objects which calls QNetworkAccessManager to see if it works correct then. Then we also have a chance to reproduce your problem.

SGaist

You do not show how you actually use it. From what you posted it looks like do not actually make any request.

thecatishere

@SGaist I've created an example project and copy pasted the code from the networkmanager and it works there. I use it by calling netManager.fromGoogle(QByteArray(url)) in Answerer.

Edit:
I tried calling the NetworkManager in the main function before the initialization of Reader.
When I delete 'Reader reader;' it works, otherwise it doesn't. Reader class has nothing to do with the NetworkManager.

SGaist

Well, as already written, with the bits you posted we can't determine what is going wrong as the code looks correct.

So if possible please provide a minimal compilable sample that shows your issue.