碰到这样一个题：编写一个MDI应用程序，在客户区从左至右滚动显示文本串，我是刚自学的MFC，在网上发现这样一段代码

1.     用MFC AppWizard新建一个工程 名为Q2的
2.     在CQ2VIEW类的OnDraw（）函数中添加以下程序
void CQ2View::OnDraw(CDC* pDC)
{
    CQ2Doc* pDoc = GetDocument();
    ASSERT_VALID(pDoc);
    // TODO: add draw code for native data here
    CPaintDC dc(this);
    CRect r1;
    LOGFONT lf;
    CString outString="滚动的文字";
    CBrush *OldBrush,NewBrush;
    CPen *OldPen,NewPen;
    CFont *OldFont,NewFont;
    COLORREF strRgb[]={RGB(255,0,0),RGB(255,255,0)};
    SetTimer(0,10,NULL);
    SetTimer(1,100,NULL);
    GetClientRect(&r1);
    pDC->GetCurrentFont()->GetLogFont(&lf);
    lf.lfCharSet=DEFAULT_CHARSET;
    lf.lfHeight=30;
    lf.lfWidth=20;
    if(x>=r1.right&&i!=1)
    {
        x=1;
        i=1;   
    }
    else if(x>=r1.right&&i!=0)
    {
        x=1;
        i=0;
    }   
    if(i==1)   
    {   
        KillTimer(0);//关闭定时器0
        strcpy(lf.lfFaceName,"黑体");//复制     
    }
    else if(i==0)
    {   
        KillTimer(1);//关闭定时器1
        strcpy(lf.lfFaceName,"宋体");
    }
    pDC->SetBkMode(TRANSPARENT);//设置背景模式
  NewFont.CreateFontIndirect(&lf);
    OldFont=pDC->SelectObject(&NewFont);
    NewPen.CreatePen(PS_SOLID,1,strRgb[i]);
    NewBrush.CreateSolidBrush(strRgb[i]);
    OldPen=pDC->SelectObject(&NewPen);
    OldBrush=pDC->SelectObject(&NewBrush);
    pDC->BeginPath();
    pDC->TextOut(x,200,outString);
    pDC->EndPath();
    pDC->StrokeAndFillPath();
    NewPen.DeleteObject();
    NewBrush.DeleteObject();
    NewFont.DeleteObject();
}
可是我不知道那个X和I表示的什么，哪位大神能够帮忙解决下啊~~~~