How to use separate threads for pushbuttons in QT (like SwingWorker in Java)

[artt]

If I define IThread::run() in Lister.cpp with definition of Lister::walk(QString path0), lower in the same file I got such errors with 2 modifications - should I define these 2 methods in different files or in inverse order?

1. void IThread::run()
{
   static void Lister::walk(QString path0);
}
 
 ERRROR:invalid use of qualified-name 'Lister::walk'
 
2.
void IThread::run()
{
   Lister::walk(QString);
}
 
ERROR:expected primary-expression before ')' token

1. void IThread::run()
{
   static void Lister::walk(QString path0);
}

 ERRROR:invalid use of qualified-name 'Lister::walk'

2.
void IThread::run()
{
   Lister::walk(QString);
}

ERROR:expected primary-expression before ')' token

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There is also run-time error with the argument of walk(pp) - so should I understand that I need just walk()?
QString p="C:\\C";
Object::connect: No such slot Lister::walk(pp) in ..\Filewalker2\main.cpp:32