P2P编程

开发平台：
Visual C++

CategoryCombobox.cpp：源码内容
							// CategoryCombobox.cpp : implementation file
//
#include "stdafx.h"
#include "testbt.h"
#include "CategoryCombobox.h"
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif
/////////////////////////////////////////////////////////////////////////////
// CCategoryCombobox
CCategoryCombobox::CCategoryCombobox()
{
}
CCategoryCombobox::~CCategoryCombobox()
{
}
BEGIN_MESSAGE_MAP(CCategoryCombobox, CComboBox)
	//{{AFX_MSG_MAP(CCategoryCombobox)
	ON_WM_DESTROY()
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()
/////////////////////////////////////////////////////////////////////////////
// CCategoryCombobox message handlers
void CCategoryCombobox::DrawItem( LPDRAWITEMSTRUCT pDIStruct )
{
	assert(m_pimgList);
	static CString sFolder, tmpStr;									// No Need To Reallocate Each Time
	CDC dcContext;
	CRect rItemRect(pDIStruct->rcItem);
	CRect rBlockRect(rItemRect);
	CRect rTextRect(rBlockRect);
	CBrush brFrameBrush;
	int iItem = pDIStruct -> itemID;
	int	iState = pDIStruct -> itemState;
	int iImageIndex = 0;
	int iIndent;
	COLORREF crColor = GetSysColor(COLOR_WINDOW);
	COLORREF crNormal = GetSysColor(COLOR_WINDOW);
	COLORREF crSelected = GetSysColor(COLOR_HIGHLIGHT);
	COLORREF crText = GetSysColor(COLOR_WINDOWTEXT);
	// Attach the CDC object
	if(!dcContext.Attach(pDIStruct -> hDC ))
		return;
	brFrameBrush.CreateStockObject(BLACK_BRUSH);
	// Draw folder text and icon
	// If an item is selected...	
	if( iItem != -1 )
	{
		// Get text for normal and disabled
		CString sFolder;
		GetLBText(iItem, sFolder);
		LPSFOLDER tmpFolder = (LPSFOLDER)GetItemDataPtr(iItem);
		iIndent = tmpFolder->m_iIndent;
		// if draw edit text, then no indent.
		if (iState & ODS_COMBOBOXEDIT)
			iIndent = 1;
		// Calculate icon display area and set the width
		rBlockRect.DeflateRect(CSize(2, 2));
		rBlockRect.right = ICONWIDTH * iIndent;
		// Calculate Text Area
		// Set start of text offset a bit
		rTextRect.left += (ICONWIDTH * iIndent) + 2;
		rTextRect.top += 2;
		CSize size = dcContext.GetTextExtent(sFolder);
		rTextRect.right = rTextRect.left + size.cx + 4;
		////////////////////////////////////////////////
		// draw focus select.
		if(iState & ODS_SELECTED)
		{
			dcContext.SetTextColor((0x00FFFFFF & ~(crText)));
			dcContext.SetBkColor( crSelected );
			dcContext.FillSolidRect( &rTextRect, crSelected );
		}
		else
		{
			dcContext.SetTextColor( crText );		
			dcContext.SetBkColor( crNormal );
			dcContext.FillSolidRect( &rTextRect, crNormal );
		}
		
		// If item has the focus...draw the focus rectangle. 
		// **** useless.
		if( iState & ODS_FOCUS )
			dcContext.DrawFocusRect( &rTextRect );
		////////////////////////////////////////////////
		// draw text and image.
		iImageIndex = tmpFolder->m_iImageIndex;
		if( iState & ODS_DISABLED )
		{
			crColor = GetSysColor(COLOR_INACTIVECAPTIONTEXT);
			dcContext.SetTextColor(crColor);
			CPoint pt(pDIStruct->rcItem.left, pDIStruct->rcItem.top);
			pt.x = pDIStruct->rcItem.left + ((iIndent - 1) * ICONWIDTH);
			m_pimgList->Draw(&dcContext, iImageIndex, pt, ILD_TRANSPARENT);
		}
		else
		{
			CPoint pt(pDIStruct->rcItem.left, pDIStruct->rcItem.top);
			pt.x = pDIStruct->rcItem.left + ((iIndent - 1) * ICONWIDTH);
			m_pimgList->Draw(&dcContext, iImageIndex, pt, ILD_NORMAL);
		}
		dcContext.SetBkMode(TRANSPARENT);
		dcContext.TextOut(rTextRect.left, rTextRect.top, sFolder);
	}
	// Detach DC
	dcContext.Detach();
}
void CCategoryCombobox::OnDestroy() 
{
	DeleteAllItems();
	CComboBox::OnDestroy();	
}
void CCategoryCombobox::DeleteAllItems()
{
	// Iterate through the items destroying all of the
	// associated data
	LPSFOLDER tmpFolder;
	int iListCount = GetCount();
	for (int x = 0; x < iListCount; x++)
	{
		tmpFolder = (LPSFOLDER)GetItemDataPtr(x);
		if (tmpFolder)
			delete tmpFolder;
	}
	ResetContent();
}

						