复选框的下拉列表

1、用自定义的CCheckComboBox类做带复选框的下拉列表1、添加Combo Box控件2.、改属性Style：DropList  ； Owner Draw：Fixed ； Has string：true ；Sort：false3、头文件中添加：     CCheckComboBox m_comboBox;4、DoDataExchange(CDataExchange* pDX)中添加：     DDX_Control(pDX, IDC_COMBO1, m_comb

2、oBox);5、对话框初始化时添加    m_comboBox.AddString(_T("1");/加入项目    m_comboBox.AddString(_T("2");    m_comboBox.AddString(_T("3");    m_comboBox.AddString(_T("4");    m_comboBox.SetCheck(0, TRUE

3、);/设置选择状态    m_comboBox.SetCheck(1, FALSE);    m_comboBox.SetCheck(2, TRUE);    m_comboBox.SetCheck(3, TRUE);    #if !defined(AFX_CHECKCOMBOBOX_H_66750D93_95DB_11D3_9325_444553540000_INCLUDED_)#define AFX_CHECKCOMBOBOX_H_66750D93_95DB_

4、11D3_9325_444553540000_INCLUDED_#if _MSC_VER > 1000#pragma once#endif / _MSC_VER > 1000class CCheckComboBox : public CComboBoxpublic:CCheckComboBox();virtual CCheckComboBox();BOOL Create(DWORD dwStyle, const RECT& rect, CWnd* pParentWnd, UINT nID);/ Selects all/unselects the specified item

5、INT SetCheck(INT nIndex, BOOL bFlag);/ Returns checked stateBOOL GetCheck(INT nIndex);/ Selects all/unselects allvoid SelectAll(BOOL bCheck = TRUE);protected:/ ClassWizard generated virtual function overrides/AFX_VIRTUAL(CCheckComboBox)protected:virtual void DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruc

6、t);virtual void MeasureItem(LPMEASUREITEMSTRUCT lpMeasureItemStruct);/AFX_VIRTUAL/AFX_MSG(CCheckComboBox)afx_msg LRESULT OnCtlColorListBox(WPARAM wParam, LPARAM lParam);afx_msg LRESULT OnGetText(WPARAM wParam, LPARAM lParam);afx_msg LRESULT OnGetTextLength(WPARAM wParam, LPARAM lParam);afx_msg void

7、OnDropDown();/AFX_MSGDECLARE_MESSAGE_MAP()public:   CString m_strText;protected:/ Routine to update the textvoid RecalcText();/ The subclassed COMBOLBOX window (notice the 'L')HWND m_hListBox;/ The string containing the text to displayBOOL m_bTextUpdated;/ A flag used in MeasureIte

8、m, see comments thereBOOL m_bItemHeightSet;/AFX_INSERT_LOCATION/ Microsoft Visual C+ will insert additional declarations immediately before the previous line.#endif / !defined(AFX_CHECKCOMBOBOX_H_66750D93_95DB_11D3_9325_444553540000_INCLUDED_) /*  CheckComboBox.cpp  */ CheckComboBox.c

9、pp / Written by Magnus Egelberg (magnus.egelberglundalogik.se)/ Copyright (C) 1999, Lundalogik AB, Sweden. All rights reserved./ /#include "stdafx.h"/ #include "CheckCombo.h"#include "CheckComboBox.h"#ifdef _DEBUG#define new DEBUG_NEW#undef THIS_FILEstatic char THIS_FIL

10、E = _FILE_;#endifstatic WNDPROC m_pWndProc = 0;static CCheckComboBox *m_pComboBox = 0;BEGIN_MESSAGE_MAP(CCheckComboBox, CComboBox)/AFX_MSG_MAP(CCheckComboBox)ON_MESSAGE(WM_CTLCOLORLISTBOX, OnCtlColorListBox)ON_MESSAGE(WM_GETTEXT, OnGetText)ON_MESSAGE(WM_GETTEXTLENGTH, OnGetTextLength)ON_CONTROL_REFL

11、ECT(CBN_DROPDOWN, OnDropDown)/AFX_MSG_MAPEND_MESSAGE_MAP()/ The subclassed COMBOLBOX message handler/extern "C" LRESULT FAR PASCAL ComboBoxListBoxProc(HWND hWnd, UINT nMsg, WPARAM wParam, LPARAM lParam)switch (nMsg)      case WM_RBUTTONDOWN:     / If you want

12、to select all/unselect all using the    / right button, remove this ifdef. Personally, I don't really like it    #if FALSE     if (m_pComboBox != 0)       INT nCount = m_pComboBox->GetCount();    &#

13、160; INT nSelCount = 0;      for (INT i = 0; i < nCount; i+)        if (m_pComboBox->GetCheck(i)        nSelCount+;            m_pComboBox->SelectAll(n

14、SelCount != nCount);      / Make sure to invalidate this window as well      InvalidateRect(hWnd, 0, FALSE);      m_pComboBox->GetParent()->SendMessage(WM_COMMAND, MAKELONG(GetWindowLong(m_pComboBox->m_hWnd, GWL_ID),

15、 CBN_SELCHANGE), (LPARAM)m_pComboBox->m_hWnd);         #endif    break;      / Make the combobox always return -1 as the current selection. This   / causes the lpDrawItemStruct->itemID in DrawItem() to be -1 &

16、#160; / when the always-visible-portion of the combo is drawn   case LB_GETCURSEL:     return -1;      case WM_CHAR:     if (wParam = VK_SPACE)      / Get the current selection     INT nIndex = CallWi

17、ndowProcA(m_pWndProc, hWnd, LB_GETCURSEL, wParam, lParam);     CRect rcItem;     SendMessage(hWnd, LB_GETITEMRECT, nIndex, (LONG)(VOID *)&rcItem);     InvalidateRect(hWnd, rcItem, FALSE);     / Invert the check mark&

18、#160;    m_pComboBox->SetCheck(nIndex, !m_pComboBox->GetCheck(nIndex);     / Notify that selection has changed     m_pComboBox->GetParent()->SendMessage(WM_COMMAND, MAKELONG(GetWindowLong(m_pComboBox->m_hWnd, GWL_ID), CBN_SELCHANG

19、E), (LPARAM)m_pComboBox->m_hWnd);     return 0;        break;      case WM_LBUTTONDOWN:     CRect rcClient;    GetClientRect(hWnd, rcClient);    CPoint pt;    pt.x = L

20、OWORD(lParam);    pt.y = HIWORD(lParam);    if (PtInRect(rcClient, pt)      INT nItemHeight = SendMessage(hWnd, LB_GETITEMHEIGHT, 0, 0);     INT nTopIndex   = SendMessage(hWnd, LB_GETTOPINDEX, 0, 0);   

21、60; / Compute which index to check/uncheck     INT nIndex = nTopIndex + pt.y / nItemHeight;     CRect rcItem;     SendMessage(hWnd, LB_GETITEMRECT, nIndex, (LONG)(VOID *)&rcItem);     if (PtInRect(rcItem, pt)  &

22、#160;    / Invalidate this window      InvalidateRect(hWnd, rcItem, FALSE);      m_pComboBox->SetCheck(nIndex, !m_pComboBox->GetCheck(nIndex);      / Notify that selection has changed   

23、60;  m_pComboBox->GetParent()->SendMessage(WM_COMMAND, MAKELONG(GetWindowLong(m_pComboBox->m_hWnd, GWL_ID), CBN_SELCHANGE), (LPARAM)m_pComboBox->m_hWnd);             / Do the default handling now (such as close the popup  &

24、#160; / window when clicked outside)    break;      case WM_LBUTTONUP:     / Don't do anything here. This causes the combobox popup    / windows to remain open after a selection has been made    return 0;  

25、 return CallWindowProc(m_pWndProc, hWnd, nMsg, wParam, lParam); CCheckComboBox:CCheckComboBox()m_hListBox       = 0;m_bTextUpdated   = FALSE;m_bItemHeightSet = FALSE;CCheckComboBox:CCheckComboBox()BOOL CCheckComboBox:Create(DWORD dwStyle, const RECT&

26、rect, CWnd* pParentWnd, UINT nID)/ Remove the CBS_SIMPLE and CBS_DROPDOWN styles and add the one I'm designed fordwStyle &= 0xF;dwStyle |= CBS_DROPDOWNLIST;/ Make sure to use the CBS_OWNERDRAWVARIABLE styledwStyle |= CBS_OWNERDRAWVARIABLE;/ Use default strings. We need the itemdata to store

27、checkmarksdwStyle |= CBS_HASSTRINGS;return CComboBox:Create(dwStyle, rect, pParentWnd, nID);LRESULT CCheckComboBox:OnCtlColorListBox(WPARAM wParam, LPARAM lParam) / If the listbox hasn't been subclassed yet, do so.if (m_hListBox = 0)    HWND hWnd = (HWND)lParam;   if (hWnd !=

28、 0 && hWnd != m_hWnd)     / Save the listbox handle    m_hListBox = hWnd;    / Do the subclassing    m_pWndProc = (WNDPROC)GetWindowLong(m_hListBox, GWL_WNDPROC);    SetWindowLong(m_hListBox, GWL_WNDPROC, (LONG)ComboB

29、oxListBoxProc);   return DefWindowProc(WM_CTLCOLORLISTBOX, wParam, lParam);void CCheckComboBox:DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct) HDC dc = lpDrawItemStruct->hDC;CRect rcBitmap = lpDrawItemStruct->rcItem;CRect rcText   = lpDrawItemStruct->rcItem;CString strText;/

30、 0 - No check, 1 - Empty check, 2 - CheckedINT nCheck = 0;/ Check if we are drawing the static portion of the comboboxif (LONG)lpDrawItemStruct->itemID < 0)    / Make sure the m_strText member is updated   RecalcText();   / Get the text   strText = m_str

31、Text;   / Don't draw any boxes on this item   nCheck = 0;/ Otherwise it is one of the itemselse    GetLBText(lpDrawItemStruct->itemID, strText);   nCheck = 1 + (GetItemData(lpDrawItemStruct->itemID) != 0);   TEXTMETRIC metrics;  

32、GetTextMetrics(dc, &metrics);   rcBitmap.left    = 0;   rcBitmap.right   = rcBitmap.left + metrics.tmHeight + metrics.tmExternalLeading + 6;   rcBitmap.top    += 1;   rcBitmap.bottom -= 1;   rcText.left = r

33、cBitmap.right; if (nCheck > 0)    SetBkColor(dc, GetSysColor(COLOR_WINDOW);   SetTextColor(dc, GetSysColor(COLOR_WINDOWTEXT);   UINT nState = DFCS_BUTTONCHECK;   if (nCheck > 1)    nState |= DFCS_CHECKED;   / Draw the checkm

34、ark using DrawFrameControl   DrawFrameControl(dc, rcBitmap, DFC_BUTTON, nState);if (lpDrawItemStruct->itemState & ODS_SELECTED)    SetBkColor(dc, GetSysColor(COLOR_HIGHLIGHT);   SetTextColor(dc, GetSysColor(COLOR_HIGHLIGHTTEXT);else    SetBkColor(dc, Ge

35、tSysColor(COLOR_WINDOW);   SetTextColor(dc, GetSysColor(COLOR_WINDOWTEXT);/ Erase and drawExtTextOut(dc, 0, 0, ETO_OPAQUE, &rcText, 0, 0, 0);DrawText(dc, ' ' + strText, strText.GetLength() + 1, &rcText, DT_SINGLELINE|DT_VCENTER|DT_END_ELLIPSIS);if (lpDrawItemStruct->item

36、State & (ODS_FOCUS|ODS_SELECTED) = (ODS_FOCUS|ODS_SELECTED)   DrawFocusRect(dc, &rcText);void CCheckComboBox:MeasureItem(LPMEASUREITEMSTRUCT lpMeasureItemStruct) CClientDC dc(this);CFont *pFont = dc.SelectObject(GetFont();if (pFont != 0)    TEXTMETRIC metrics;  

37、 dc.GetTextMetrics(&metrics);   lpMeasureItemStruct->itemHeight = metrics.tmHeight + metrics.tmExternalLeading;   / An extra height of 2 looks good I think.    / Otherwise the list looks a bit crowded.   lpMeasureItemStruct->itemHeight += 2; 

38、60; / This is needed since the WM_MEASUREITEM message is sent before   / MFC hooks everything up if used in i dialog. So adjust the   / static portion of the combo box now   if (!m_bItemHeightSet)     m_bItemHeightSet = TRUE;    SetItemHeig

39、ht(-1, lpMeasureItemStruct->itemHeight);      dc.SelectObject(pFont);/ Make sure the combobox window handle is updated since/ there may be many CCheckComboBox windows active/void CCheckComboBox:OnDropDown() m_pComboBox = this;/ Selects/unselects all items in the list/void CChe

40、ckComboBox:SelectAll(BOOL bCheck)INT nCount = GetCount();for (INT i = 0; i < nCount; i+)   SetCheck(i, bCheck);/ By adding this message handler, we may use CWnd:GetText()/LRESULT CCheckComboBox:OnGetText(WPARAM wParam, LPARAM lParam)/ Make sure the text is updatedRecalcText();if (lParam

41、 = 0)   return 0;/ Copy the 'fake' window textlstrcpyn(LPWSTR)lParam, m_strText, (INT)wParam);return m_strText.GetLength();/ By adding this message handler, we may use CWnd:GetTextLength()/LRESULT CCheckComboBox:OnGetTextLength(WPARAM, LPARAM)/ Make sure the text is updatedRecalcText();return m_strText.GetLength();/ This routine steps thru all the items and builds/ a string containing the checked items/void CCheckComboBox:RecalcText()i