Queued connection fails on own class

[^NyAw^]

Hi,

I'm getting this error on my application

QObject::connect: Cannot queue arguments of type 'CModbusResponse&'
(Make sure 'CModbusResponse&' is registered using qRegisterMetaType().)

QObject::connect: Cannot queue arguments of type 'CModbusResponse&'
(Make sure 'CModbusResponse&' is registered using qRegisterMetaType().)

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CModbusResponse is a class that inherits from CModbusMessage. I have registered the classes with "qRegisterMetaType".
The problem is that the connection returns true if "QtirectConnection" is used, but it returns false if "Qt::QueuedConnection" is used.

The classes have their copy constructor.

Thanks,

[jpn]

Are you sure you register the type before calling connect()? Also make sure you didn't try to connect non-const reference parameters.

[^NyAw^]

Hi,

Are you sure you register the type before calling connect()? Also make sure you didn't try to connect non-const reference parameters.

Yes, I do it in MainWindow constructor

Also make sure you didn't try to connect non-const reference parameters

I think that are non-const references. How have I to declare them const?

Thanks,

[jpn]

I think that are non-const references. How have I to declare them const?

Yes. Parameters of queued signals will be serialized. You cannot pass non-const references as queued signal parameters (nor should you do that with direct signals either).