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QNetworkAccessManager never sends request

  • I am writing an application where I need to call a web service to get initialisation data.
    In my app I have got a splash screen with a new thread for executing my initialisation code.
    This is all surrounded by an event loop so seems to work fine. However in my new thread When I try to make a call to my service I get nothing and it just sits there indefinitely. I can step through and see the request being created. this is then passed int the QNetworkAccessManager's get function. I then connect up all the signals and slots.
    However nothing is being sent and none of the slots are triggered.
    Am I missing something simple here?

    Here is a rough example of what my request function is doing:
    void httpRequest::getRequest(QUrl& url)
    if (_response) { return; }

    _responseError = false;
    _response = _webCtrl.get(*_request);
            (void (QNetworkReply::*)(QNetworkReply::NetworkError))&QNetworkReply::error,


  • Hey,

    I have not exactly solved my issue but have worked around it. I have now removed all processing threads and put all my QNetwork... code into the slashScreen. This seems to have fixed it as the requests are now actually going and I am getting all the slots triggered.
    Still unsure why this exact same code did not work through another thread.

  • Qt Champions 2017

    Which thread created request ? Is it worker thread or main thread. If it is worker thread, try creating in worker thread. It may be something to with ownership of NetworkManager object.

  • Hi,
    Yes, I have a wrapper class that creates the QNetworkAccessManager and all of the request objects. This class is instanced in the run method of a QRunnable in a pointer with all signals and slots connected.
    I can see the request being created but none of the slots ever get called.
    If I call the exact same code from within the main thread it all works fine.
    Will try and put together an example project showing this and post it later.

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