Slot gets not invoked

[makopo]

Hi,

I had thought, I understand signals and slots, but there is a problem I did not get solved. I would like to give a short overview:
I have three classes. In the constructor of ReceiveData I implement two connect functions which send data from worker to a slot:

ReceiveData::ReceiveData(QWidget* parent)  
{
    QObject::connect(m_worker, &Worker::SendData, this, &ReceiveData::PublishData, Qt::QueuedConnection);
    QObject::connect(m_worker, &Worker::SendData, m_convertData, &Converter::ConvertData, Qt::QueuedConnection);
}

Calling slots in these class works. ReceiveData is derived from QWidget.

I have another worker class, named Converter. Here I implement a slot thats converts my data. This slot also emits a signal that sends the converted data to a slot in another class, named StoreData. The class Converter is derived from QObject.

void Converter::ConvertData(Datatype* data) {
    //... Converting stuff ...
    emit SendConvertedData(m_convertedData);
}

Than the third class StoreData implements the connect function like this and is also derived from QWidget:

QObject::connect(m_converter, &Converter::SendConvertedData, this, &StoreData::CopyData, Qt::DirectConnection);

So the converted data is send to a slot which copied the data. And here is the problem, because in the class StoreData the call of CopyData did not work. But when I move the last connect function to the class ReceiveData the slot CopyData gets invoked.
All classes runs in the same thread, so I did not understand why there is a problem.

[Christian Ehrlicher]

QObject::connect(m_converter,...

Are you sure this instance really emits the signal and not another one?

All classes runs in the same thread,

Why the QueuedConnection and DirectConnection then? Not needed...

ConvertData(T* data)

Template class? How did you solve the problem with Q_OBJECT macro there?

[SGaist]

Hi,

In addition to @Christian-Ehrlicher, is
@makopo said in Slot gets not invoked:

m_worker

properly initialized ?

[makopo]

@Christian-Ehrlicher said in Slot gets not invoked:

Are you sure this instance really emits the signal and not another one?
Why the QueuedConnection and DirectConnection then? Not needed.

ReceiveData, ConvertData and StoreData runs in the same thread, in detail in the main thread. The class Worker that send the raw data runs ins an seperate thread.

Template class? How did you solve the problem with Q_OBJECT macro there?

No template class. I wrote T to mark any data type.

@SGaist said in Slot gets not invoked:

m_worker

properly initialized ?

m_worker is initialized. I add qDebug to the slots PublishData and ConvertData and can see that this connection works.
There is only a problem with this connection:

QObject::connect(m_converter, &Converter::SendConvertedData, this, &StoreData::CopyData, Qt::DirectConnection);

that runs in the class ReceiveData but not in in the StoreData class.
m_converter is also initialized. Setting the connection type to Qt::Autoconnection does not show a positive result.

[Christian Ehrlicher]

@makopo said in Slot gets not invoked:

m_converter is also initialized.

This was not the question - the question was if this is really the object where you do the emit or if there is another one around. Please add a debug statement to print out the address of m_converter there and this where you do the emit to check if they're the same. I would guess they're not.

[makopo]

@Christian-Ehrlicher
Thanks for the advice. I will check this in the afternoon.

[makopo]

Problem solved. Thanks for your advices!

[SGaist]

@makopo What was the issue ?