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void CRechteckDlg::OnButtonRectangle() 
{
	CString cstrButtonText;
	GetDlgItem(IDC_BUTTON_RECTANGLE)->GetWindowText(cstrButtonText);
	if (cstrButtonText == "Start") {
		m_iFlag = 1;
		bTimer = TRUE;	

		CWinThread* pThread = AfxBeginThread (threadFunction, this);
		GetDlgItem(IDC_BUTTON_RECTANGLE)->SetWindowText("Stop");
	}
	else{		
		m_iFlag = 0;
		bTimer = FALSE;
		GetDlgItem(IDC_BUTTON_RECTANGLE)->SetWindowText("Start");	
	}	
}

UINT CRechteckDlg::threadFunction(LPVOID pParam)
{
	CRechteckDlg* pDlg = (CRechteckDlg*) pParam;
	pDlg->threadRun();

	return 0;
}

VOID CRechteckDlg::threadRun()
{
	while (m_iFlag) {

		// Rechteck ausserhalb des definierten Bereichs ?
		if (rectdata.left >= 400)
			SetRect();					

		// Device Kontext des Fensters holen
		CDC* pDC = GetDC();
		CBrush brush(RGB (255, 0, 0));

		pDC->SelectObject(&brush);
		pDC->Rectangle(&rectdata);
		pDC->DeleteDC();

	}
}

VOID CRechteckDlg::SetRect()
{
	rectdata.left = 10;
	rectdata.top = 10;
	rectdata.bottom = 40;
	rectdata.right = 80;
}

void CRechteckDlg::OnTimer(UINT nIDEvent) 
{
	if (bTimer) {

		RedrawWindow(&rectdata, NULL, RDW_INVALIDATE | RDW_UPDATENOW | RDW_ERASE );
		rectdata.left++;
		rectdata.right++;		
	}

	CDialog::OnTimer(nIDEvent);
}