Object::connect:cannot queue arguments of type ' qmap<qstring,qstring> ' (to use qregistermetatype<stringmap> To register)

Qobject::connect:cannot queue arguments of type ' qmap<qstring,qstring> ', (make sure ' qmap<qstring,qstring> ' is registered using Qregistermetatype ().).

The above error occurs only when cross-thread signaling is passed. Because Qmap is a basic type of QT-aware, it does not require a re-registration in the meta-object system, and there is no problem running in the same thread.

Source:

CPP Code

1. //  thread class  thread.h   
2. class thread:PUBLIC&NBSP;QTHREAD&NBSP;&NBSP;
3. {  
4.     q_object  
5.   
6. PUBLIC:&NBSP;&NBSP;
7.     thread () {}  
8.     ~thread () {}  
9.   
10. PROTECTED:&NBSP;&NBSP;
11.     virtual void run ();   
12.   
13. signals:  
14.     void sendmsg (const qmap<qstring,qstring> &msgs) ;   
15. }  

CPP Code

1. Signal Reception class Test.h
2. Test (Thread *th): m_th (TH)
3. {
4. //Different threads are connected in queue mode
5. Connect (m_th,signal (sendmsg (const qmap<qstring,qstring> &)),This,slot (handle (const qmap<  Qstring,qstring> &), qt::queuedconnection);
6. }

Solution: Register to Metype with the Qregistermetatype () method

CPP Code

1. Thread.h
2. typedef qmap<qstring,qstring> STRINGMAP; the//typedef operator is an alias for Qmap
4. void sendmsg (const STRINGMAP &);

CPP Code

1. Test.h
2. Test (Thread *th): m_th (TH)
3. {
4. //Register Qmap to meta-object system
5. Qregistermetatype<stringmap> ("Stringmap");
6. Connect (m_th,signal (sendmsg (const STRINGMAP &)),This,slot (handle (const STRINGMAP &)), Qt::  Queuedconnection);
7. }

http://tcspecial.iteye.com/blog/1897006

Object::connect:cannot queue arguments of type ' qmap<qstring,qstring> ' (to use Qregistermetatype<stringmap > Registration)