Qt 5.6 - QNetworkReply finished() never called

Question

I'm trying to do a simple GET request using QNetworkReply but finished() never get's called, here is my code

QtTest::QtTest(QWidget *parent):QWidget(parent){
  ui.setupUi(this);

  auto network_access_manager = new QNetworkAccessManager(this);
  auto reply = network_access_manager->get(QNetworkRequest(QUrl("http://www.whatsmyip.org/")));
  connect(reply, SIGNAL(finished()), this, SLOT(download_finished()));


qDebug() << "Started";

}

void QtTest::download_finished() {

  qDebug() << "Finished";

}

If I check output on startup I get

QObject::connect: Cannot connect (null)::aboutToQuit() to QNativeWifiEngine::closeHandle()

Exception thrown at 0x749040F8 (KernelBase.dll) in QtTest.exe: 0x000006A6: The binding handle is invalid.

Check [this answer](http://stackoverflow.com/a/37926541/1329652) for a complete example and see if it works for you. If it does, you have other problems. If it doesn't, your Qt install is somehow broken/corrupt. — Kuba hasn't forgotten Monica, Jul 07 '16 at 14:43
For my case, the QtTest was already released before download_finished was called. — Zhang, Dec 19 '19 at 02:53

rflobao · Answer 1 · 2016-07-05T23:44:25.767

0

Verify if you are declaring download_finished() as a slot.

class QtTest : public QObject
{
    Q_OBJECT
public:
    QtTest(QObject *parent = 0);

private slots:
    void download_finished();
};

edited Jul 05 '16 at 23:44

answered Jul 05 '16 at 23:03

rflobao

562
2
8

The macro Q_OBJECT is declared to class? In my tests its work fine. – rflobao Jul 05 '16 at 23:13
Yes. I've also tried `connect(reply, &QNetworkReply::finished, this, &QtTest::download_finished);` – QtTest Jul 05 '16 at 23:14
Try delete manually the files "Makefile" generated in the build and recompile. – rflobao Jul 05 '16 at 23:22

score -1 · Answer 2 · answered Jul 05 '16 at 23:03

-1

change your definition of download_finished to include the reply;

The signal is; finished(QNetworkReply *reply) so

  QtTest::download_finished(QNetworkReply *reply)
  {
     .... etc

Make sure to include the parameter in the connect statement.

answered Jul 05 '16 at 23:03

john elemans

2,578
2
15
26

1

If I do that I get error. QObject::connect: No such signal QNetworkReplyHttpImpl::finished(QNetworkReply *reply) in qttest.cpp:18 – QtTest Jul 05 '16 at 23:09
The correct format is; connect(manager,SIGNAL(finished(QNetworkReply*)),this, SLOT(replyFinished(QNetworkReply*))); – john elemans Jul 05 '16 at 23:20
that doesn't get called either. – QtTest Jul 05 '16 at 23:26
are there error messages in the application output on startup? – john elemans Jul 05 '16 at 23:30
`QObject::connect: Cannot connect (null)::aboutToQuit() to QNativeWifiEngine::closeHandle() Exception thrown at 0x749040F8 (KernelBase.dll) in QtTest.exe: 0x000006A6: The binding handle is invalid.` – QtTest Jul 05 '16 at 23:33
That is a separate error, remove that connect or fix it first. – john elemans Jul 06 '16 at 15:45
There's no `QNetworkReply::finished(QNetworkReply*)` signal! You're thinking of `QNetworkAccessManager::finished`, but that's not the right type in this case. – Kuba hasn't forgotten Monica Jul 07 '16 at 14:41
The documents say that both signals are sent; http://doc.qt.io/qt-5/qnetworkaccessmanager.html#finished. But I see that finished() alone should work. – john elemans Jul 07 '16 at 19:55

Qt 5.6 - QNetworkReply finished() never called

2 Answers2