undefined reference to vtable in Threads.

[prasanth.nvs]

In the following code i got compilation erros like below

/thread.cpp:20: undefined reference to `vtable for MyThread'

thread.cpp:6: undefined reference to `vtable for MyThread'

MyThread.h file is

#ifndef MYTHREAD_H
#define MYTHREAD_H
 
#include <QThread>
#include <QObject>
 
class MyThread:public QThread
{
    Q_OBJECT
public:
    MyThread(QWidget* aParent);
    ~MyThread();
 
public slots:
    void Finished();
 
protected:
    void run();
};
 
#endif //MYTHREAD_H

#ifndef MYTHREAD_H
#define MYTHREAD_H

#include <QThread>
#include <QObject>

class MyThread:public QThread
{
    Q_OBJECT
public:
    MyThread(QWidget* aParent);
    ~MyThread();

public slots:
    void Finished();

protected:
    void run();
};

#endif //MYTHREAD_H

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and MyThread.cpp is

#include "thread.h"
#include <iostream.h>
#include <QMetaType>
 
 
MyThread::MyThread(QWidget* aParent)
{
    qRegisterMetaType<MyThread*>("MyThread");
    QObject::connect(this,SIGNAL(finished()),this,SLOT(Finished()));
    if(!isRunning())
    {
        start();
    }
    else
    {
        return;
    }
}
 
MyThread::~MyThread()
{
 
}
 
 void MyThread::run()
{
    cout <<"Hello :" << endl;
}
 
 
void MyThread::Finished()
{
    cout << "In Finishes:" << endl;
}

#include "thread.h"
#include <iostream.h>
#include <QMetaType>


MyThread::MyThread(QWidget* aParent)
{
    qRegisterMetaType<MyThread*>("MyThread");
    QObject::connect(this,SIGNAL(finished()),this,SLOT(Finished()));
    if(!isRunning())
    {
        start();
    }
    else
    {
        return;
    }
}

MyThread::~MyThread()
{

}

 void MyThread::run()
{
    cout <<"Hello :" << endl;
}


void MyThread::Finished()
{
    cout << "In Finishes:" << endl;
}

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and main.cpp is

int main(int argc,char* argv[])
{
    QtopiaApplication app(argc,argv);
 
    QWidget* lWidget = new QWidget;
    lWidget->setGeometry(0,0,240,320);
 
    MyThread* lThread   = new MyThread(lWidget);
 
    Widget->show();
 
    return app.exec();
}

int main(int argc,char* argv[])
{
    QtopiaApplication app(argc,argv);

    QWidget* lWidget = new QWidget;
    lWidget->setGeometry(0,0,240,320);

    MyThread* lThread   = new MyThread(lWidget);

    Widget->show();

    return app.exec();
}

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Now whts the problem in above code and wts the reason for that.