multithread problem

Why the following codes works first "for loop" and then "progressbar" but not parallerly?

Code:

---

void CProgressbarDlg::OnButton1()
{
hThread=AfxBeginThread(ThreadFunc,&m_Progress,THREAD_PRIORITY_HIGHEST);


  for(int i=0;i<50000;i++)
  {
                m_edit=m_edit+"C";
               
                UpdateData(FALSE);
  }
 
//  hThread->SuspendThread();
 
}


UINT ThreadFunc(LPVOID param1)
{
  CProgressCtrl *param=(CProgressCtrl*)param1;
  BOOL d=TRUE;
        param->SetRange(1,10);
        while(1)
        {
                if (d)       
                {
                        param->SetPos(param->GetPos()+1);
                        if (param->GetPos()==10)
                                d=FALSE;
                }
                else
                {
                        param->SetPos(param->GetPos()-1);
                        if (param->GetPos()==1)
                                d=TRUE;
                }
                Sleep(500);
        }
        return 0;
}

---

Read about MFC and multithreading. You can't reuse MFC objects across threads. It's simply not possible.

I'm pretty sure I something like this before, and it worked fine.

Did you try changing the thread priotity from THREAD_PRIORITY_HIGHEST to THREAD_PRIORITY_NORMAL, and see what hapens ?

Yes I tried it.
But if I create two more threds besides the base thred.
then the child threds work parallely.

But I am curious to know why do I need two more threds if I need only one more thred.

But in console programs it works fine.