From Forum Nokia Wiki

ID	CS001428	Creation date	June 16, 2009
Platform	S60 3rd Edition, FP1, FP2 S60 5th Edition	Tested on devices	Nokia 5800 XpressMusic
Category	Qt for Symbian	Subcategory	Base/System

Keywords (APIs, classes, methods, functions): QThread, qRegisterMetaType, Q_DECLARE_METATYPE

Overview

This code snippet demonstrates how to use your own class as a signal and slot parameter in QThread.

Note: In order to use this code, you need to have Qt for S60 installed on your platform.

Preconditions

• Install latest Qt for S60 see Qt for S60 - Installation packages
• Check this link for installation guide: How to install the package.
• Go through this article: Getting started with Qt for S60

Header

#include "MyError.h"
 
public slots:
    void receiveError(MyError*);

Source

// Before using mythread QThread we have to register our custom metatype
qRegisterMetaType<MyError>("MyError");
 
// Create thread class
thread = new MyThread(this);
 
// Singal and slot connect
QObject::connect(thread, SIGNAL(error(MyError*)),
        this, SLOT(receiveError(MyError*)));
 
// Start thread
thread->start();

Custom data class as a signal/slot parameter

The header file of MyError. Q_DECLARE_METATYPE(MyError) makes the type MyError known to QMetaType.

class MyError : public QObject
    {
    public:
        MyError(int error, QObject* parent = 0);
        virtual ~MyError();
 
    private:
        int err;
    };
 
// This macro makes the type MyError known to QMetaType
Q_DECLARE_METATYPE(MyError)

See also

• CS001427 - Using threads in Qt
• For more information about QThread, see QThread Class Reference.

Postconditions

Your own data class can be used as a signal and slot parameter in QThread.