MFC 自绘进度条

从 CProgress类派生出 CTextProgress CTextProgress::CTextProgress() {     m_crProgress = RGB(0,255,0);     m_crBlank = RGB(255,255,255);     m_crText = RGB(0,25,255); } void CTextProgress::OnPaint()  {     //CPaintDC dc(this); // device context for painting     // TODO: Add your message handler code here     PAINTSTRUCT ps;     CDC *pDC = BeginPaint(&ps);     int nPos = GetPos();     int nMin,nMax;     GetRange(nMin,nMax);     CString csPos;     csPos.Format("%d%%",nPos*100/(nMax-nMin));          CRect clientRC;     GetClientRect(clientRC);     CSize sztext = pDC->GetTextExtent(csPos); //获取字符串的高度和宽度     int nX = (clientRC.Width() - sztext.cx) /2; //计算中心位置     int nY = (clientRC.Height() -sztext.cy) /2;     pDC->SetBkMode(TRANSPARENT);               //获取单位刻度     double dFraction = (double) clientRC.Width()/(nMax-nMin);     int nLeft = nPos * dFraction; //计算左边距     CRect leftRC = clientRC;     leftRC.right = nLeft;     CRect rightRC = clientRC;     rightRC.left = nLeft;          pDC->FillRect(leftRC,&CBrush(m_crProgress));     pDC->FillRect(rightRC,&CBrush(m_crBlank));     pDC->SetTextColor(m_crText);     pDC->TextOut(nX,nY,csPos);     ReleaseDC(pDC);     EndPaint(&ps);     // Do not call CProgressCtrl::OnPaint() for painting messages }