listboxex.cpp

哈夫曼编码解码演示程序

// ListBoxEx.cpp : implementation file
//

#include "stdafx.h"
#include "huffman.h"
#include "ListBoxEx.h"

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

/////////////////////////////////////////////////////////////////////////////
// CListBoxEx

CListBoxEx::CListBoxEx()
{
	width = 0;
	m_bkBrush.CreateSolidBrush(RGB(128,128,128));
}

CListBoxEx::~CListBoxEx()
{
}


BEGIN_MESSAGE_MAP(CListBoxEx, CListBox)
	//{{AFX_MSG_MAP(CListBoxEx)
	ON_WM_CTLCOLOR_REFLECT()
	ON_WM_VSCROLL()
	ON_WM_HSCROLL()
	ON_WM_DRAWITEM_REFLECT()
	ON_CONTROL_REFLECT(LBN_SELCHANGE, OnSelchange)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CListBoxEx message handlers
void CListBoxEx::updateWidth(LPCTSTR s)
{
	CClientDC dc(this);
	CFont * f = CListBox::GetFont();
    dc.SelectObject(f);
    CSize sz = dc.GetTextExtent(s, _tcslen(s));
    sz.cx += 3 * ::GetSystemMetrics(SM_CXBORDER);
    if(sz.cx > width)
	{ /* extend */
		width = sz.cx;
		CListBox::SetHorizontalExtent(width);
	} /* extend */
}

int CListBoxEx::AddString(LPCTSTR s)
{
	int result = CListBox::AddString(s);
	if(result < 0)
		return result;
	updateWidth(s);
	return result;
}

int CListBoxEx::InsertString(int i, LPCTSTR s)
{
	int result = CListBox::InsertString(i, s);
	if(result < 0)
		return result;
	updateWidth(s);
	return result;
}

void CListBoxEx::ResetContent()
{
	CListBox::ResetContent();
	width = 0;
}

int CListBoxEx::DeleteString(int n)
{
	int result = CListBox::DeleteString(n);
	if(result < 0)
		return result;
	CClientDC dc(this);

	CFont * f = CListBox::GetFont();
	dc.SelectObject(f);
    width = 0;
	for(int i = 0; i < CListBox::GetCount(); i++)
	{ /* scan strings */
		CString s;
		CListBox::GetText(i, s);
		CSize sz = dc.GetTextExtent(s);
		sz.cx += 3 * ::GetSystemMetrics(SM_CXBORDER);
		if(sz.cx > width)
			width = sz.cx;
	} /* scan strings */
	CListBox::SetHorizontalExtent(width);
	return result;
}

/*void CListBoxEx::OnPaint() 
{
	CPaintDC dc(this); // device context for painting
/*	CDC memDC;
	CRect rect;
	GetClientRect(&rect);
	memDC.CreateCompatibleDC(&dc);
	CBitmap bmp;
	bmp.CreateCompatibleBitmap(&dc,rect.Width(),rect.Height());
	memDC.SelectObject(&bmp);
	CRgn rgn;
	rgn.CreateRectRgnIndirect(rect);

	memDC.FillRect(rect,&CBrush(RGB(0,0,255)));
	dc.BitBlt(0,0,rect.Width(),rect.Height(),&memDC,0,0,SRCCOPY);//
	// Do not call CListBox::OnPaint() for painting messages
}*/

HBRUSH CListBoxEx::CtlColor(CDC* pDC, UINT nCtlColor) 
{

//	pDC->SetTextColor(RGB(205,205,0));
//	pDC->SetBkMode(TRANSPARENT);
//	CRect rect;
//	GetClientRect(rect);
//    pDC->FillRect(rect,	&m_bkBrush);
//	return (HBRUSH) m_bkBrush;

	// TODO: Return a non-NULL brush if the parent's handler should not be called
	return NULL;
}

/*void CListBoxEx::OnPaint() 
{
	CPaintDC dc(this); // device context for painting
	
	CDC memDC;
	CRect rect;
	GetClientRect(&rect);
//	rect.right=rect.left+GetHorizontalExtent();
	memDC.CreateCompatibleDC(&dc);	
	CBitmap bmp;
	bmp.CreateCompatibleBitmap(&dc,rect.Width(),rect.Height());	
	memDC.SelectObject(&bmp);
	CRgn rgn;
	rgn.CreateRectRgnIndirect(rect);
    memDC.SelectClipRgn(&rgn);
	rgn.DeleteObject();
	CWnd::DefWindowProc(WM_PAINT,(WPARAM)memDC.m_hDC,0);
    
    CDC maskDC;
	maskDC.CreateCompatibleDC(&dc);
    CBitmap maskBmp;
	maskBmp.CreateBitmap(rect.Width(),rect.Height(),1,1,NULL);
	maskDC.SelectObject(&maskBmp);

	memDC.SetBkColor(::GetSysColor(COLOR_WINDOW));
	maskDC.BitBlt(0,0,rect.Width(),rect.Height(),&memDC,rect.left
		,rect.top,SRCCOPY);

	memDC.SetBkColor(RGB(49,70,96));
	memDC.SetTextColor(RGB(255,255,255));

	memDC.BitBlt(rect.left,rect.top,rect.Width(),rect.Height(),
		&maskDC,rect.left,rect.top,SRCAND);

	dc.BitBlt(rect.left,rect.top,rect.Width(),rect.Height(),
		&memDC,rect.left,rect.top,SRCCOPY);
	memDC.DeleteDC();
	maskDC.DeleteDC();
	bmp.DeleteObject();
	maskBmp.DeleteObject();
}*/

void CListBoxEx::OnVScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar) 
{
	InvalidateRect(NULL);	
	CListBox::OnVScroll(nSBCode, nPos, pScrollBar);
}
void CListBoxEx::OnHScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar) 
{
//	updateWidth();
	Invalidate();
	CListBox::OnHScroll(nSBCode, nPos, pScrollBar);
}


void CListBoxEx::DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct) 
{	
}

void CListBoxEx::OnSelchange() 
{
	Invalidate();
}