Displaying progressbar using threading in win 32 applicaition!

[Rajakumarrs]

In my application I have a simple module were I will read files for some process that will take
few seconds..so I thought of displaying a progress bar(using worker thread) while the files are in progress.I have created a thread (code shown below) and also I designed a dialog window with progress control.I used the function MyThreadFunctio n below to display the progressbar but it just shows only one time and disappears,I am not sure how to make it work.I tried my best inspite of the fact that I am new to threading.

reading files
    void ReadMyFiles()
    {
    
      for(int i = 0; i < fileCount ; fileCount++)
      {  
      CWinThread* myThread = AfxBeginThread((AFX_THREADPROC)MyThreadFunction,NULL);
      tempState = *(checkState + index);
      if(tempCheckState == NOCHECKBOX)
      {
        //my operations
      }
      else//CHECKED or UNCHECKED
      {
        //myoperation
      }
      myThread->PostThreadMessage(WM_QUIT,NULL,NULL);
      }
    }

thread functions

    UINT MyThreadFunction(LPARAM lparam)
    {
      HWND dialogWnd = CreateWindowEx(0,WC_DIALOG,L"Proccessing...",WS_OVERLAPPEDWINDOW|WS_VISIBLE,
              600,300,280,120,NULL,NULL,NULL,NULL);
      HWND pBarWnd = CreateWindowEx(NULL,PROGRESS_CLASS,NULL,WS_CHILD|WS_VISIBLE|PBS_MARQUEE,40,20,200,20,
                  dialogWnd,(HMENU)IDD_PROGRESS,NULL,NULL);
              
      MSG msg;
        
      PostMessage( pBarWnd, PBM_SETRANGE, 0, MAKELPARAM( 0, 100 ) );
      PostMessage(pBarWnd,PBM_SETPOS,0,0);
      while(PeekMessage(&msg,NULL,NULL,NULL,PM_NOREMOVE))
      {
        if(msg.message == WM_QUIT)
        {
          DestroyWindow(dialogWnd);
          return 1;
        }
        AfxGetThread()->PumpMessage();
        Sleep(40);
      }
      return 1;
      
    
    }