www.pudn.com > 用于显示音效的柱状器.zip > HistogramCtrl.cpp

// HistogramCtrl.cpp : implementation file 
// 
 
// stdafx.cpp : source file that includes just the standard includes 
//	CPanel.pch will be the pre-compiled header 
//	stdafx.obj will contain the pre-compiled type information 
 
#include "stdafx.h" 
 
#include "HistogramCtrl.h" 
 
#ifdef _DEBUG 
#define new DEBUG_NEW 
#undef THIS_FILE 
static char THIS_FILE[] = __FILE__; 
#endif 
 
///////////////////////////////////////////////////////////////////////////// 
// CHistogramCtrl 
 
CHistogramCtrl::CHistogramCtrl() 
{ 
	m_nPos      = 0; 
	m_nLower    = 0; 
	m_nUpper    = 100; 
} 
 
CHistogramCtrl::~CHistogramCtrl() 
{ 
} 
 
 
BEGIN_MESSAGE_MAP(CHistogramCtrl, CWnd) 
	//{{AFX_MSG_MAP(CHistogramCtrl) 
	ON_WM_PAINT() 
	//}}AFX_MSG_MAP 
END_MESSAGE_MAP() 
 
 
///////////////////////////////////////////////////////////////////////////// 
// CSpikeCtrl message handlers 
 
BOOL CHistogramCtrl::Create(DWORD dwStyle, const RECT& rect, CWnd* pParentWnd, UINT nID, CCreateContext* pContext)  
{ 
	// TODO: Add your specialized code here and/or call the base class 
	static CString className = AfxRegisterWndClass(CS_HREDRAW | CS_VREDRAW); 
 
	return  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); 
} 
 
void CHistogramCtrl::SetRange(UINT nLower, UINT nUpper) 
{ 
	ASSERT(nLower >= 0 && nLower < 0xffff); 
	ASSERT(nUpper > nLower && nUpper < 0xffff); 
 
	m_nLower = nLower; 
	m_nUpper = nUpper; 
	 
	InvalidateCtrl(); 
} 
 
void CHistogramCtrl::InvalidateCtrl() 
{ 
	// Small optimization that just invalidates the client area 
	// (The borders don't usually need updating) 
	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); 
		// draw scale 
		m_MemDC.SetBkColor(RGB(0,0,0)); 
		CBrush bkBrush(HS_HORIZONTAL,RGB(0,128,0)); 
    m_MemDC.FillRect(rcClient,&bkBrush); 
	} 
 
	InvalidateRect(rcClient); 
} 
 
UINT CHistogramCtrl::SetPos(UINT nPos) 
{ 
	if (nPos > m_nUpper) 
		nPos = m_nUpper; 
 
	if (nPos < m_nLower) 
		nPos = m_nLower; 
 
	UINT nOld = m_nPos; 
	m_nPos = nPos; 
 
	DrawSpike(); 
 
	Invalidate(); 
 
	return nOld; 
} 
 
void CHistogramCtrl::OnPaint()  
{ 
	CPaintDC dc(this); // device context for painting 
	 
	// TODO: Add your message handler code here 
	 
	// Do not call CWnd::OnPaint() for painting messages 
	// draw scale 
	CRect rcClient; 
	GetClientRect(rcClient); 
 
	// draw scale 
	if (m_MemDC.GetSafeHdc() != NULL) 
	{ 
		dc.BitBlt(0, 0, rcClient.Width(), rcClient.Height(), &m_MemDC, 0, 0, SRCCOPY); 
	} 
} 
 
void CHistogramCtrl::DrawSpike() 
{ 
//	CClientDC dc(this); 
	UINT  nRange = m_nUpper - m_nLower; 
	CRect rcClient; 
	GetClientRect(rcClient); 
 
	if (m_MemDC.GetSafeHdc() != NULL) 
	{ 
		m_MemDC.BitBlt(0, 0, rcClient.Width(), rcClient.Height(), &m_MemDC, 4, 0, SRCCOPY); 
 
		CRect rcTop(rcClient.right - 4, 0, rcClient.right - 2, rcClient.bottom); 
		rcTop.top  = (long) (((float) (m_nPos - m_nLower) / nRange) * rcClient.Height()); 
		rcTop.top  = rcClient.bottom - rcTop.top; 
 
		// draw scale 
		CRect rcRight = rcClient; 
		rcRight.left = rcRight.right - 4; 
		m_MemDC.SetBkColor(RGB(0,0,0)); 
 
    CBrush bkBrush(HS_HORIZONTAL,RGB(0,128,0));   
    m_MemDC.FillRect(rcRight,&bkBrush); 
 
		// draw current spike 
		CBrush brush(RGB(0,255,0)); 
		m_MemDC.FillRect(rcTop, &brush); 
	} 
}