viewhistogram.cpp

主要介绍vc++6.0的编程过程

// ViewHistogram.cpp : implementation file
//

#include "stdafx.h"
#include "ImageView.h"
#include "ViewHistogram.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CViewHistogram dialog


CViewHistogram::CViewHistogram(CWnd* pParent /*=NULL*/)
	: CDialog(CViewHistogram::IDD, pParent)
{
	//{{AFX_DATA_INIT(CViewHistogram)
		// NOTE: the ClassWizard will add member initialization here
	//}}AFX_DATA_INIT
	m_nCurSel = 0;
	m_pnHistogram = NULL;
}


void CViewHistogram::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CViewHistogram)
	DDX_Control(pDX, IDC_TAB1, m_Histogram);
	//}}AFX_DATA_MAP
}


BEGIN_MESSAGE_MAP(CViewHistogram, CDialog)
	//{{AFX_MSG_MAP(CViewHistogram)
	ON_NOTIFY(TCN_SELCHANGE, IDC_TAB1, OnSelchangeTab1)
	ON_WM_PAINT()
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CViewHistogram message handlers

void CViewHistogram::OnSelchangeTab1(NMHDR* pNMHDR, LRESULT* pResult) 
{

	m_nCurSel = m_Histogram.GetCurSel();
	InvalidateRect( NULL, FALSE );
	UpdateWindow();
		
	*pResult = 0;
}

void CViewHistogram::OnPaint() 
{
	CPaintDC dc(this); // device context for painting
	
	RECT Rect1;
	GetWindowRect( &Rect1 );	
	CWnd *pWnd;
	pWnd = GetDlgItem( IDC_HISTOGRAM );
	RECT Rect2;
	pWnd->GetWindowRect( &Rect2 );

	COLORREF Color = GetSysColor( COLOR_BTNFACE );
	CBrush Brush( Color );
	CPen Pen( PS_SOLID, 1, Color );
	CBrush *pOldBrush;
	CPen *pOldPen;
	CPen BlackPen( PS_SOLID, 1, RGB( 0, 0, 0 ) );
	CPen RedPen( PS_SOLID, 1, RGB( 255, 0, 0 ) );
	CPen GreenPen( PS_SOLID, 1, RGB( 0, 255, 0 ) );
	CPen BluePen( PS_SOLID, 1, RGB( 0, 0, 255 ) );
	pOldBrush = (CBrush *) dc.SelectObject( &Brush );
	pOldPen = (CPen *) dc.SelectObject( &Pen );
	int x1 = Rect2.left - Rect1.left;
	int y1 = Rect2.top - Rect1.top - 12;
	int x2 = Rect2.right - Rect1.left - 6;
	int y2 = Rect2.bottom - Rect1.top - 25;
	dc.Rectangle( x1, y1, x2, y2 );
	int midx = x1 + ( ( x2 - x1 ) / 2 );
	if( m_nCurSel == 0 ) dc.SelectObject( &BlackPen );
	else if( m_nCurSel == 3 ) dc.SelectObject( &BluePen );
	else if( m_nCurSel == 2 ) dc.SelectObject( &GreenPen );
	else dc.SelectObject( &RedPen );
	for( int i=0; i<256; i++ ){
		if( m_pnHistogram != NULL && m_pnHistogram[m_nCurSel*256+i] != 0 ){
			dc.MoveTo( midx - 128 + i, y2 - 1 );
			dc.LineTo( midx - 128 + i, y2 - m_pnHistogram[m_nCurSel*256+i] );
			}
		}
	dc.SelectObject( pOldBrush );
	dc.SelectObject( pOldPen );
}

BOOL CViewHistogram::OnInitDialog() 
{
	CDialog::OnInitDialog();
	
	TC_ITEM Item;
	int i;
	static char *pszTexts[] = { "Gray", "Red", "Green", "Blue" };
	for( i=0; i<4; i++ ){
		memset( &Item, 0, sizeof( TC_ITEM ) );
		Item.mask = TCIF_TEXT;
		Item.pszText = pszTexts[i];
		Item.iImage = -1;
		m_Histogram.InsertItem( i, &Item );
		}
	
	return TRUE;  // return TRUE unless you set the focus to a control
	              // EXCEPTION: OCX Property Pages should return FALSE
}