UI Freeze Problem

From:
"rahulthathoo" <rahul.thathoo@gmail.com>
Newsgroups:
microsoft.public.vc.mfc
Date:
10 Aug 2006 22:33:15 -0700
Message-ID:
<1155274395.681531.207000@i42g2000cwa.googlegroups.com>
My problem is that the cpu usage becomes 100% - this is because i need
to refresh the dialog after a sleep of 10 miliseconds. but the problem
is that the sleep makes the UI freeze. I thought a workaround would be
using threads. but even after using threads and events the problem
persists - the UI still freezes. Please tell me what is going wrong
here. Here is the code listing:

void Cmalt6Dlg::OnPaint()
{
.....
.....
.......
HANDLE hEvent;
    HANDLE hThread;
    DWORD dwThreadID;
    DWORD dwStatus;
    hEvent = CreateEvent( NULL,
                FALSE,
                FALSE,
                NULL
                  );
    if( hEvent == NULL ) //oops!
    {
        printf( "CreateEvent() failed!\n" );
        return;
    }

    hThread = CreateThread( NULL,
                NULL,
                (LPTHREAD_START_ROUTINE)ThreadFunction,
                (LPVOID)hEvent,
                NULL,
                &dwThreadID
                  );

    if( hThread == NULL ) //oops!
    {
        printf( "CreateThread() failed!\n" );
        CloseHandle( hEvent );
        return;
    }

    hBmp = (HBITMAP)::LoadImage(
                NULL,
                szFilename3,
                IMAGE_BITMAP,
                0,
                0,
                LR_LOADFROMFILE|LR_CREATEDIBSECTION
                );

        CBitmap* pOldBmp1;
        CBitmap* pOldBmp2;
        CPen *pOldPen, blackPen;
        blackPen.CreatePen(PS_SOLID,1,RGB(0,0,0));
        CDC* pDC = GetDC();
    int count = 0;
    while(TRUE)
    {

        dwStatus = WaitForSingleObject(hEvent,0);

        if(dwStatus == WAIT_OBJECT_0 )
        {
                .....
                .....
                }
        }
}//close OnPaint()

DWORD ThreadFunction( LPVOID lpArg )
{
    HANDLE hEvent = (HANDLE)lpArg;

    while(TRUE)
    {
        Sleep( 5 );

        SetEvent( hEvent ); //set the event state to signalled
    }

    return 0L;
}

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