CE50下绘制实时数据曲线

1、 绘制思路：做一个自定义控件插入界面中具体步骤： （1）横轴划分为若干点，使用Moveto+Lineto连线，定时刷新实现动态效果；（2）在程序中，使用CPaintDC,CClientDc,CDC,CBitMap,CBrush等绘图类；（3）绘图程序分为几大部分：注册类句柄、刷新机制、设定坐标系、绘图；部分代码如下：BOOL CLineChartCtrl:RegisterWndClass(HINSTANCE hInstance)WNDCLASSW wc;wc.lpszClassName = TEXT(LineChartCtrl); / matches class name in client。

2、return (:RegisterClass(&wc) != 0 ); void CLineChartCtrl:InvalidateCtrl()CClientDC dc(this);CRect rcClient;GetClientRect(rcClient);if (m_MemDC.GetSafeHdc() = NULL)m_MemDC.CreateCompatibleDC(&dc);m_Bitmap.CreateCompatibleBitmap(&dc,rcClient.Width(),rcClient.Height();m_MemDC.SelectObject(m_Bitmap); m_M

3、emDC.SetBkColor(RGB(255,255,255); /静态背景色CBrush bkBrush(RGB(160,160,160);m_MemDC.FillRect(rcClient,&bkBrush);InvalidateRect(rcClient, FALSE);float CLineChartCtrl:SetPos(int nIndex, float nPos)。void CLineChartCtrl:OnPaint() CPaintDC dc(this); / device context for paintingCRect rcClient;GetClientRect(r

4、cClient);/ draw scaleif (m_MemDC.GetSafeHdc() != NULL)dc.BitBlt(0, 0, rcClient.Width(), rcClient.Height(), &m_MemDC, 0, 0, SRCCOPY);void CLineChartCtrl:DrawSpike()CRect rcClient;GetClientRect(rcClient);if (m_MemDC.GetSafeHdc() != NULL) /竖线间隔宽度m_MemDC.BitBlt(0, 0, rcClient.Width(), rcClient.Height(),

5、 &m_MemDC, 20, 0, SRCCOPY);/ draw scaleCRect rcRight = rcClient;rcRight.left = rcRight.right - 20; m_MemDC.SetBkColor(RGB(255,255,255); /运行时背景色CBrush bkBrush(RGB(160,160,160); m_MemDC.FillRect(rcRight,&bkBrush);static BOOL bDrawVerticle = FALSE;bDrawVerticle = !bDrawVerticle;if (bDrawVerticle) CPen

6、pen(PS_SOLID, 1, RGB(128,128,128); /纵轴色CPen* pOldPen = m_MemDC.SelectObject(&pen);m_MemDC.MoveTo(CPoint(rcClient.right-2, rcClient.top);m_MemDC.LineTo(CPoint(rcClient.right-2, rcClient.bottom);m_MemDC.SelectObject(pOldPen);int nCount = m_items.GetSize();CLineChartItem* pItem;CPoint ptOld, ptNew;for

7、(int i=0; im_nUpper - pItem-m_nLower;ptOld.x = rcRight.left-1; / Minus one to make sure to draw inside the areaptNew.x = rcRight.right-1;ptOld.y = (int)(float)(nRange - pItem-m_nOldPos)/(float)nRange)* (float)rcRight.Height();ptNew.y = (int)(float)(nRange - pItem-m_nPos)/(float)nRange)* (float)rcRig

8、ht.Height();CPen pen(PS_SOLID, 1, pItem-m_colorLine);CPen* pOldPen = m_MemDC.SelectObject(&pen);m_MemDC.MoveTo(ptOld);m_MemDC.LineTo(ptNew);m_MemDC.SelectObject(pOldPen);BOOL CLineChartCtrl:Add(COLORREF color, float Upper, float Lower)CLineChartItem* pItem = new CLineChartItem;pItem-m_colorLine = co

9、lor;pItem-m_nLower = Lower;pItem-m_nUpper = Upper;pItem-m_nPos = 0;pItem-m_nOldPos = 0;try m_items.Add(pItem);InvalidateCtrl();return TRUE; catch (CMemoryException* e)if (pItem !=NULL) delete pItem;e-Delete();return FALSE;void CLineChartCtrl:Go()DrawSpike();Invalidate(FALSE); 注意的几点：(1) Windows CE采用u

10、nicode，必须写诸如WNDCLASSW;LoadCursorW;(2) EVC下的CBrush不能使用两个参数如CBrush(HS_Cross,RGB(0,0,0)； (3)改动stdAfx.h包含的头文件； (4)在void CVoltagecontrolDlg:DoDataExchange(CDataExchange* pDX)里加入 DDX_Control(pDX, IDC_LineChartCtrl, m_LineChart); 在BOOL CVoltagecontrolDlg:OnInitDialog()里加入 m_LineChart.SubclassDlgItem(IDC_LineChartCtrl, this); (5)在设置自定义空间属性ID必须为IDC_LineChartCtrl，CLASS为LineChartCtrl，相应程序里的注册句柄名称也设成LineChartCtrl； (6)程序中改变竖线间隔的是其宽度，而画竖线的时间间隔是2*Timer； 现有的运行效果：横轴采用五个Edit控件使时间