iconview.cpp

这是MFC Windows程序设计（第二版）书上的代码

#include <afxwin.h>
#include "IconView.h"

#define IDC_LISTBOX 100

CMyApp myApp;

/////////////////////////////////////////////////////////////////////////
// CMyApp member functions

BOOL CMyApp::InitInstance ()
{
    m_pMainWnd = new CMainWindow;
    m_pMainWnd->ShowWindow (m_nCmdShow);
    m_pMainWnd->UpdateWindow ();
    return TRUE;
}

/////////////////////////////////////////////////////////////////////////
// CMainWindow message map and member functions

BEGIN_MESSAGE_MAP (CMainWindow, CWnd)
    ON_WM_CREATE ()
    ON_WM_PAINT ()
    ON_WM_SETFOCUS ()
    ON_WM_DROPFILES ()
    ON_LBN_SELCHANGE (IDC_LISTBOX, OnSelChange)
END_MESSAGE_MAP ()

CMainWindow::CMainWindow ()
{
    CString strWndClass = AfxRegisterWndClass (
        0,
        myApp.LoadStandardCursor (IDC_ARROW),
        (HBRUSH) (COLOR_3DFACE + 1),
        myApp.LoadStandardIcon (IDI_WINLOGO)
	);

    CreateEx (0, strWndClass, _T ("IconView"),
        WS_OVERLAPPED | WS_SYSMENU | WS_CAPTION | WS_MINIMIZEBOX,
        CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
        NULL, NULL, NULL);

    CRect rect (0, 0, m_cxChar * 84, m_cyChar * 21);
    CalcWindowRect (&rect);

    SetWindowPos (NULL, 0, 0, rect.Width (), rect.Height (),
        SWP_NOZORDER | SWP_NOMOVE | SWP_NOREDRAW);
}

int CMainWindow::OnCreate (LPCREATESTRUCT lpcs)
{
    if (CWnd::OnCreate (lpcs) == -1)
        return -1;

	m_font.CreatePointFont (80, _T ("MS Sans Serif"));

    CClientDC dc (this);
    CFont* pOldFont = dc.SelectObject (&m_font);
    TEXTMETRIC tm;
    dc.GetTextMetrics (&tm);
    m_cxChar = tm.tmAveCharWidth;
    m_cyChar = tm.tmHeight + tm.tmExternalLeading;
    dc.SelectObject (pOldFont);

    m_rcImage.SetRect (m_cxChar * 4, m_cyChar * 3, m_cxChar * 46,
        m_cyChar * 19);

    m_wndGroupBox.Create (_T ("Detail"),  WS_CHILD | WS_VISIBLE | BS_GROUPBOX,
        CRect (m_cxChar * 2, m_cyChar, m_cxChar * 48, m_cyChar * 20),
        this, (UINT) -1);

    m_wndLabel.Create (_T ("Icons"), WS_CHILD | WS_VISIBLE | SS_LEFT,
        CRect (m_cxChar * 50, m_cyChar, m_cxChar * 82, m_cyChar * 2),
        this);

    m_wndIconListBox.Create (WS_CHILD | WS_VISIBLE | WS_VSCROLL |
        WS_BORDER | LBS_NOTIFY | LBS_NOINTEGRALHEIGHT,
        CRect (m_cxChar * 50, m_cyChar * 2, m_cxChar * 82, m_cyChar * 20),
        this, IDC_LISTBOX);

    m_wndGroupBox.SetFont (&m_font);
    m_wndLabel.SetFont (&m_font);

    DragAcceptFiles ();
    return 0;
}

void CMainWindow::PostNcDestroy ()
{
    delete this;
}

void CMainWindow::OnPaint ()
{
    CPaintDC dc (this);
    m_wndIconListBox.ProjectImage (&dc, m_rcImage,
        ::GetSysColor (COLOR_3DFACE));
}

void CMainWindow::OnSetFocus (CWnd* pWnd)
{
    m_wndIconListBox.SetFocus ();
}

void CMainWindow::OnDropFiles (HDROP hDropInfo)
{
	//
	// Find out how many files were dropped.
	//
    int nCount = ::DragQueryFile (hDropInfo, (UINT) -1, NULL, 0);

    if (nCount == 1) { // One file at a time, please
        m_wndIconListBox.ResetContent ();
		//
		// Extract the file's icons and add them to the list box.
		//
        char szFile[MAX_PATH];
        ::DragQueryFile (hDropInfo, 0, szFile, sizeof (szFile));
        int nIcons = (int) ::ExtractIcon (NULL, szFile, (UINT) -1);

        if (nIcons) {
            HICON hIcon;
            for (int i=0; i<nIcons; i++) {
                hIcon = ::ExtractIcon (AfxGetInstanceHandle (),
                    szFile, i);
                m_wndIconListBox.AddIcon (hIcon);
            }
        }

		//
		// Put the file name in the main window's title bar.
		//
        CString strWndTitle = szFile;
        strWndTitle += _T (" - IconView");
        SetWindowText (strWndTitle);

		//
		// Select item number 0.
		//
        CClientDC dc (this);
        m_wndIconListBox.SetCurSel (0);
        m_wndIconListBox.ProjectImage (&dc, m_rcImage,
            ::GetSysColor (COLOR_3DFACE));
    }
    ::DragFinish (hDropInfo);
}

void CMainWindow::OnSelChange ()
{
    CClientDC dc (this);
    m_wndIconListBox.ProjectImage (&dc, m_rcImage,
        ::GetSysColor (COLOR_3DFACE));
}

/////////////////////////////////////////////////////////////////////////
// CIconListBox member functions

BOOL CIconListBox::PreCreateWindow (CREATESTRUCT& cs)
{
    if (!CListBox::PreCreateWindow (cs))
        return FALSE;

    cs.dwExStyle |= WS_EX_CLIENTEDGE;
    cs.style &= ~(LBS_OWNERDRAWVARIABLE | LBS_SORT);
    cs.style |= LBS_OWNERDRAWFIXED;
    return TRUE;
}

void CIconListBox::MeasureItem (LPMEASUREITEMSTRUCT lpmis)
{
    lpmis->itemHeight = 36;
}

void CIconListBox::DrawItem (LPDRAWITEMSTRUCT lpdis)
{
    CDC dc;
    dc.Attach (lpdis->hDC);
    CRect rect = lpdis->rcItem;
    int nIndex = lpdis->itemID;

    CBrush* pBrush = new CBrush;
    pBrush->CreateSolidBrush (::GetSysColor ((lpdis->itemState &
        ODS_SELECTED) ? COLOR_HIGHLIGHT : COLOR_WINDOW));
    dc.FillRect (rect, pBrush);
    delete pBrush;

    if (lpdis->itemState & ODS_FOCUS)
        dc.DrawFocusRect (rect);

    if (nIndex != (UINT) -1)
        dc.DrawIcon (rect.left + 4, rect.top + 2,
            (HICON) GetItemData (nIndex));

    dc.Detach ();
}

int CIconListBox::AddIcon (HICON hIcon)
{
    int nIndex = AddString (_T (""));
    if ((nIndex != LB_ERR) && (nIndex != LB_ERRSPACE))
        SetItemData (nIndex, (DWORD) hIcon);
    return nIndex;
}

void CIconListBox::ProjectImage (CDC* pDC, LPRECT pRect,
    COLORREF clrBackColor)
{
    CDC dcMem;
    dcMem.CreateCompatibleDC (pDC);

    CBitmap bitmap;
    bitmap.CreateCompatibleBitmap (pDC, 32, 32);
    CBitmap* pOldBitmap = dcMem.SelectObject (&bitmap);

    CBrush* pBrush = new CBrush (clrBackColor);
    dcMem.FillRect (CRect (0, 0, 32, 32), pBrush);
    delete pBrush;

    int nIndex = GetCurSel ();
    if (nIndex != LB_ERR)
        dcMem.DrawIcon (0, 0, (HICON) GetItemData (nIndex));

    pDC->StretchBlt (pRect->left, pRect->top, pRect->right - pRect->left,
        pRect->bottom - pRect->top, &dcMem, 0, 0, 32, 32, SRCCOPY);

    dcMem.SelectObject (pOldBitmap);
}