graphctrl.cpp

wince图形界面的开发

  // x units
  //m_dcGrid.SetTextAlign (TA_CENTER|TA_TOP) ;
  
  m_dcGrid.ExtTextOut (((m_rectPlot.left+m_rectPlot.right)/2)-30, 
                    m_rectPlot.bottom+12, ETO_CLIPPED,NULL,m_strXUnitsString,m_strXUnitsString.GetLength() ,NULL) ;

  // restore the font
  m_dcGrid.SelectObject(oldFont) ;

  // y units
  oldFont = m_dcGrid.SelectObject(&yUnitFont) ;
  m_dcGrid.ExtTextOut (((m_rectClient.left+m_rectPlot.left)/2)-20, 
                    ((m_rectPlot.bottom+m_rectPlot.top)/2)+38, ETO_CLIPPED,NULL,m_strYUnitsString,m_strYUnitsString.GetLength() ,NULL) ;
  m_dcGrid.SelectObject(oldFont) ;

  // at this point we are done filling the the grid bitmap, 
  // no more drawing to this bitmap is needed until the setting are changed
  
  // if we don't have one yet, set up a memory dc for the plot
  if (m_dcPlot.GetSafeHdc() == NULL)
  {
    m_dcPlot.CreateCompatibleDC(&dc) ;
    m_bitmapPlot.CreateCompatibleBitmap(&dc, m_nClientWidth, m_nClientHeight) ;
    m_pbitmapOldPlot = m_dcPlot.SelectObject(&m_bitmapPlot) ;
  }

  // make sure the plot bitmap is cleared
  m_dcPlot.SetBkColor (m_crBackColor) ;
  m_dcPlot.FillRect(m_rectClient, &m_brushBack) ;

  // finally, force the plot area to redraw
  InvalidateRect(m_rectClient) ;


}
/************************************************************************************
Function Name	:	Create

Class Name		:	MECGraphCtrl

Description		:	It creates the Graph control

Argument		:	DWORD dwStyle, const RECT& rect, CWnd* pParentWnd, UINT nID

Return			:	BOOL
*************************************************************************************/
BOOL MECGraphCtrl::Create(DWORD dwStyle, const RECT& rect, 
                         CWnd* pParentWnd, UINT nID) 
{
  BOOL result ;
  static CString className = AfxRegisterWndClass(CS_HREDRAW | CS_VREDRAW) ;
  result = CWnd::CreateEx(WS_EX_CLIENTEDGE | WS_EX_STATICEDGE, 
                          className, NULL, dwStyle, 
                          rect.left, rect.top, rect.right-rect.left, rect.bottom-rect.top,
                          pParentWnd->GetSafeHwnd(), (HMENU)nID) ;
  if (result != 0)
    InvalidateCtrl() ;
  return result ;
} // Create
/************************************************************************************
Function Name	:	OnSize

Class Name		:	MECGraphCtrl

Description		:	Actually it is a message handle, the window size is being initialized from this handler

Argument		:	UINT nType, int cx, int cy

Return			:	void
*************************************************************************************/
void MECGraphCtrl::OnSize(UINT nType, int cx, int cy) 
{
	CWnd::OnSize(nType, cx, cy);
	
	// TODO: Add your message handler code here
	GetClientRect(m_rectClient) ;

	// set some member variables to avoid multiple function calls
	m_nClientHeight = m_rectClient.Height() ;
	m_nClientWidth  = m_rectClient.Width() ;

	// the "left" coordinate and "width" will be modified in 
	// InvalidateCtrl to be based on the width of the y axis scaling
	m_rectPlot.left   = 20 ;  
	m_rectPlot.top    = 10 ;
	m_rectPlot.right  = m_rectClient.right-10 ;
	m_rectPlot.bottom = m_rectClient.bottom-25 ;

	// set some member variables to avoid multiple function calls
	m_nPlotHeight = m_rectPlot.Height() ;
	m_nPlotWidth  = m_rectPlot.Width() ;

	// set the scaling factor for now, this can be adjusted 
	// in the SetRange functions
	m_dVerticalFactor = (double)m_nPlotHeight / m_dRange ; 

}

void MECGraphCtrl::OnPaint() 
{
	CPaintDC dc(this); // device context for painting
	
	// TODO: Add your message handler code here
	CDC memDC ;
	CBitmap memBitmap ;
	CBitmap* oldBitmap ; // bitmap originally found in CMemDC
  
	memDC.CreateCompatibleDC(&dc) ;
	memBitmap.CreateCompatibleBitmap(&dc, m_nClientWidth, m_nClientHeight) ;
	oldBitmap = (CBitmap *)memDC.SelectObject(&memBitmap) ;

	if (memDC.GetSafeHdc() != NULL)
	{
		// first drop the grid on the memory dc
		memDC.BitBlt(0, 0, m_nClientWidth, m_nClientHeight, 
			         &m_dcGrid, 0, 0, SRCCOPY) ;
		// now add the plot on top as a "pattern" via SRCPAINT.
		// works well with dark background and a light plot
		memDC.BitBlt(0, 0, m_nClientWidth, m_nClientHeight, 
			         &m_dcPlot, 0, 0, SRCPAINT) ;  //SRCPAINT
		// finally send the result to the display
		dc.BitBlt(0, 0, m_nClientWidth, m_nClientHeight, 
			      &memDC, 0, 0, SRCCOPY) ;
	}

	memDC.SelectObject(oldBitmap) ;
	// Do not call CWnd::OnPaint() for painting messages
}
/************************************************************************************
Function Name	:	SetRange

Class Name		:	MECGraphCtrl

Description		:	It sets the minimum, maximum and decimal ratios to the Y Axis

Argument		:	double dLower, double dUpper, int nDecimalPlaces

Return			:	void
*************************************************************************************/
void MECGraphCtrl::SetRange(double dLower, double dUpper, int nDecimalPlaces)
{
    ASSERT(dUpper > dLower) ;

    m_dLowerLimit     = dLower ;
	m_dUpperLimit     = dUpper ;
	m_nYDecimals      = nDecimalPlaces ;
	m_dRange          = m_dUpperLimit - m_dLowerLimit ;
	m_dVerticalFactor = (double)m_nPlotHeight / m_dRange ; 
    // clear out the existing garbage, re-start with a clean plot
    InvalidateCtrl() ;

}
/************************************************************************************
Function Name	:	SetXUnits

Class Name		:	MECGraphCtrl

Description		:	It sets the  X axis unit as "Time in second"

Argument		:	CString string

Return			:	void
*************************************************************************************/
void MECGraphCtrl::SetXUnits(CString string)
{
  m_strXUnitsString = string ;
  // clear out the existing garbage, re-start with a clean plot
  InvalidateCtrl() ;
}  // SetXUnits

/************************************************************************************
Function Name	:	SetYUnits

Class Name		:	MECGraphCtrl

Description		:	It sets the  Y axis unit as "Volume in ml"

Argument		:	CString string

Return			:	void
*************************************************************************************/
void MECGraphCtrl::SetYUnits(CString string)
{
  m_strYUnitsString = string ;
  // clear out the existing garbage, re-start with a clean plot
  InvalidateCtrl() ;
}
/************************************************************************************
Function Name	:	SetGridColor

Class Name		:	MECGraphCtrl

Description		:	It sets the Grid or X and Y axis colors

Argument		:	COLORREF color

Return			:	void
*************************************************************************************/
void MECGraphCtrl::SetGridColor(COLORREF color)
{
  m_crGridColor = color ;
  // clear out the existing garbage, re-start with a clean plot
  InvalidateCtrl() ;
}  // SetGridColor
/************************************************************************************
Function Name	:	SetPlotColor

Class Name		:	MECGraphCtrl

Description		:	It sets the drawing color of the curve

Argument		:	COLORREF color

Return			:	void
*************************************************************************************/
void MECGraphCtrl::SetPlotColor(COLORREF color)
{
  m_crPlotColor = color ;
  m_penPlot.DeleteObject() ;
  m_penPlot.CreatePen(PS_SOLID, 2, m_crPlotColor) ;
  // clear out the existing garbage, re-start with a clean plot
  InvalidateCtrl() ;
}  // SetPlotColor
/************************************************************************************
Function Name	:	SetBackgroundColor

Class Name		:	MECGraphCtrl

Description		:	It sets the background color of the window

Argument		:	COLORREF color

Return			:	void
*************************************************************************************/
void MECGraphCtrl::SetBackgroundColor(COLORREF color)
{
  m_crBackColor = color ;
  m_brushBack.DeleteObject() ;
  m_brushBack.CreateSolidBrush(m_crBackColor) ;
  // clear out the existing garbage, re-start with a clean plot
  InvalidateCtrl() ;
}  // SetBackgroundColor
/************************************************************************************
Function Name	:	SetXRange

Class Name		:	MECGraphCtrl

Description		:	It sets the X axis description values

Argument		:	double dLower, double dUpper, int nDecimalPlaces

Return			:	void
*************************************************************************************/
void MECGraphCtrl::SetXRange(double dLower, double dUpper, int nDecimalPlaces)
{
	ASSERT(dUpper > dLower) ;
	m_dXLower     = dLower ;
	m_dXUpper     = dUpper ;
	m_nXDecimals  = nDecimalPlaces ;
	m_XRange          = m_dXUpper - m_dXLower ;
	m_dHorizontalFactor = (double)m_nPlotWidth / m_XRange ; 
    // clear out the existing garbage, re-start with a clean plot
	InvalidateCtrl() ;
}