const QEvent::Type THREAD_FINISHED_EVENT = static_cast<QEvent::Type>(QEvent::User + 111);
class TFinishedEvent : public QEvent
{
public:
    TFinishedEvent(const int thread_id) :
                   QEvent ( THREAD_FINISHED_EVENT ),
                   id ( thread_id ) {}
    void post(QObject *receiver)
    {
        QApplication::postEvent( receiver, new TFinishedEvent( id ) );
    }
    int  getID() const { return id; }
private:
    int       id;
};

new TFinishedEvent( id ) 

void MainWindow::customEvent(QEvent *event)
{
    if ( event -> type() == THREAD_FINISHED_EVENT )
    {
        ui -> teInfo -> append("Message received, ID="
        + QString::number( static_cast<TFinishedEvent *>(event) -> ID() ) );
    }
}