Qt: (Nearly) synchronous QNetworkAccessManager calls
The QNetworkAccessManager class is very user-friendly, but it makes asynchronous calls. I was in the need for synchronous calls to handle my HTTP communication, but I did not want the overhead of another thread, so I googled a bit and finally came up with a short call to an event loop that processed the request. Like this:
QNetworkAccessManager * pnam = new QNetworkAccessManager(this); // the slot was declared at another place connect(pnam, SIGNAL(finished(QNetworkReply *)), this, SLOT(loginFinished(QNetworkReply*))); QNetworkRequest req(QUrl("http://foo.bar")); pnam->post(req, postData); // execute an event loop to process the request (nearly-synchronous) QEventLoop eventLoop; // also dispose the event loop after the reply has arrived connect(pnam, SIGNAL(finished(QNetworkReply *)), &eventLoop, SLOT(quit())); eventLoop.exec();
This way my user-defined slot for the pnam->finished() signal was called immediately, and I could be sure to have the HTTP reply at the end of this code snippet.