Tricks of the Windows Gam…ming Gurus (2nd Edition)/Disc2.iso/msdn_vcb/samples/vc98/mfc/general/ctrltest/custlist.cpp

C/C++ Source or Header | 1998-03-27 | 4.8 KB | 184 lines

// custlist.cpp : custom listbox
//
// This is a part of the Microsoft Foundation Classes C++ library.
// Copyright (C) 1992-1998 Microsoft Corporation
// All rights reserved.
//
// This source code is only intended as a supplement to the
// Microsoft Foundation Classes Reference and related
// electronic documentation provided with the library.
// See these sources for detailed information regarding the
// Microsoft Foundation Classes product.

#include "stdafx.h"
#include "ctrltest.h"

/////////////////////////////////////////////////////////////////////////////
// Custom Listbox - containing colors

class CColorListBox : public CListBox
{
public:
// Operations
    void AddColorItem(COLORREF color);

// Implementation
    virtual void MeasureItem(LPMEASUREITEMSTRUCT lpMIS);
    virtual void DrawItem(LPDRAWITEMSTRUCT lpDIS);
    virtual int CompareItem(LPCOMPAREITEMSTRUCT lpCIS);
};

void CColorListBox::AddColorItem(COLORREF color)
{
    // add a listbox item
    AddString((LPCTSTR) color);
        // Listbox does not have the LBS_HASSTRINGS style, so the
        //  normal listbox string is used to store an RGB color
}

/////////////////////////////////////////////////////////////////////////////

#define COLOR_ITEM_HEIGHT   20

void CColorListBox::MeasureItem(LPMEASUREITEMSTRUCT lpMIS)
{
    // all items are of fixed size
    // must use LBS_OWNERDRAWVARIABLE for this to work
    lpMIS->itemHeight = COLOR_ITEM_HEIGHT;
}

void CColorListBox::DrawItem(LPDRAWITEMSTRUCT lpDIS)
{
    CDC* pDC = CDC::FromHandle(lpDIS->hDC);
    COLORREF cr = (COLORREF)lpDIS->itemData; // RGB in item data

    if (lpDIS->itemAction & ODA_DRAWENTIRE)
    {
        // Paint the color item in the color requested
        CBrush br(cr);
        pDC->FillRect(&lpDIS->rcItem, &br);
    }

    if ((lpDIS->itemState & ODS_SELECTED) &&
        (lpDIS->itemAction & (ODA_SELECT | ODA_DRAWENTIRE)))
    {
        // item has been selected - hilite frame
        COLORREF crHilite = RGB(255-GetRValue(cr),
                        255-GetGValue(cr), 255-GetBValue(cr));
        CBrush br(crHilite);
        pDC->FrameRect(&lpDIS->rcItem, &br);
    }

    if (!(lpDIS->itemState & ODS_SELECTED) &&
        (lpDIS->itemAction & ODA_SELECT))
    {
        // Item has been de-selected -- remove frame
        CBrush br(cr);
        pDC->FrameRect(&lpDIS->rcItem, &br);
    }
}

int CColorListBox::CompareItem(LPCOMPAREITEMSTRUCT lpCIS)
{
    COLORREF cr1 = (COLORREF)lpCIS->itemData1;
    COLORREF cr2 = (COLORREF)lpCIS->itemData2;
    if (cr1 == cr2)
        return 0;       // exact match

    // first do an intensity sort, lower intensities go first
    int intensity1 = GetRValue(cr1) + GetGValue(cr1) + GetBValue(cr1);
    int intensity2 = GetRValue(cr2) + GetGValue(cr2) + GetBValue(cr2);
    if (intensity1 < intensity2)
        return -1;      // lower intensity goes first
    else if (intensity1 > intensity2)
        return 1;       // higher intensity goes second

    // if same intensity, sort by color (blues first, reds last)
    if (GetBValue(cr1) > GetBValue(cr2))
        return -1;
    else if (GetGValue(cr1) > GetGValue(cr2))
        return -1;
    else if (GetRValue(cr1) > GetRValue(cr2))
        return -1;
    else
        return 1;
}

/////////////////////////////////////////////////////////////////////////////
// Dialog class

class CCustListDlg : public CDialog
{
protected:
    CColorListBox  m_colors;
public:
    //{{AFX_DATA(CCustListDlg)
        enum { IDD = IDD_CUSTOM_LIST };
    //}}AFX_DATA
    CCustListDlg()
        : CDialog(CCustListDlg::IDD)
        { }

    // access to controls is through inline helpers
    BOOL OnInitDialog();

    //{{AFX_MSG(CCustListDlg)
        virtual void OnOK();
    //}}AFX_MSG
    DECLARE_MESSAGE_MAP();
};

BEGIN_MESSAGE_MAP(CCustListDlg, CDialog)
    //{{AFX_MSG_MAP(CCustListDlg)
    ON_LBN_DBLCLK(IDC_LISTBOX1, OnOK)       // double click for OK
    //}}AFX_MSG_MAP
END_MESSAGE_MAP()

BOOL CCustListDlg::OnInitDialog()
{
    // subclass the control
    VERIFY(m_colors.SubclassDlgItem(IDC_LISTBOX1, this));

    // add 8 colors to the listbox (primary + secondary color only)
    for (int red = 0; red <= 255; red += 255)
        for (int green = 0; green <= 255; green += 255)
            for (int blue = 0; blue <= 255; blue += 255)
                m_colors.AddColorItem(RGB(red, green, blue));

    return TRUE;
}

void CCustListDlg::OnOK()
{
    // get the final color
    int nIndex = m_colors.GetCurSel();
    if (nIndex == -1)
    {
        CString str;
        str.LoadString(IDS_PLEASE_SELECT_COLOR);
        MessageBox(str);
        m_colors.SetFocus();
        return;
    }
    DWORD color = m_colors.GetItemData(nIndex);

#ifdef _DEBUG
    // normally do something with it...
    TRACE1("final color RGB = 0x%06lX\n", color);
#endif

    EndDialog(IDOK);
}

/////////////////////////////////////////////////////////////////////////////
// Run the test

void CTestWindow::OnTestCustomList()
{
    TRACE0("running dialog with custom listbox (owner draw)\n");
    CCustListDlg dlg;
    dlg.DoModal();
}

/////////////////////////////////////////////////////////////////////////////