QObject::connect: Cannot queue arguments of type

问题：

Hi!

I have a small problem concerning two threads and signals/slots connected between them.

My connect looks like this.

1. ...
2. qRegisterMetaType < QVector < QVector < int >  >  > ( "MyArray" ) ;
3. ...
4. connect (sender , SIGNAL (dataChanged ( QVector < QVector < int >  > ) ) ,receiver , SLOT (hasDataChanged ( QVector < QVector < int >  > ) ) ) ;

If the signal is being emitted, I get this error:

1. QObject :: connect : Cannot queue arguments of type 'QVector<QVector<int> >'
2. (Make sure  'QVector<QVector<int> >' is registered  usingqRegisterMetaType ( ). )

Also note that I have my sig/slots with a reference, but if I used a connect like this:

1. connect (sender , SIGNAL (dataChanged ( QVector < QVector < int >  >& ) ) ,receiver , SLOT (hasDataChanged ( QVector < QVector < int >  >& ) ) ) ;

I’m getting this:
Object::connect: No such signal dataChanged(QVector<QVector<int> >&)

Sender

1. signals :
2.     void dataChanged ( const  QVector < QVector < int >  >  &data ) ;

Receiver

1. public  slots :
2.      void hasDataChanged ( const  QVector < QVector < int >  >  &data ) ;

How can I achieve a connection, do I need to put Q_DECLARE_METATYPE somewhere?

Thanks for your help!

解决方法：

1. typedef  QVector < QVector < int >  > MyArray ;
2. // ...
3. qRegisterMetaType <MyArray > ( "MyArray" ) ;
4. // ...
5. connect (
6.      this , SIGNAL (blurbDone2 (MyArray ) ) ,
7.      this , SLOT (slotBlurb2 (MyArray ) ) ,
8.      Qt :: QueuedConnection ) ;
9.  
10. // with this signatures:
11. signals :
12.      void blurbDone2 ( const MyArray  &bb ) ;
13.  
14. protected  slots :
15.      void slotBlurb2 ( const MyArray  &bb ) ;
    
    

转自：http://qt-project.org/forums/viewthread/2884