经过两天的编码调试，完成了一个自动过滤选择的组合框，具有以下优点：
1。丝毫不妨碍组合框原有的功能
2。根据用户在编辑框里已经输入的单词，从组合框的列表选项过滤出匹配的项，并使用下拉列表显示出来以供用户选择。
3。不需要特别的设置。从View\ClassWizard\Member Variables里生成一个CComboBox，然后在源文件里把CComboBox替换成CACComboBox即可；或者让ClassWizard认识CACComboBox(删除MyApp.clw，选View\ClassWizard，按提示重新生成MyApp.clw，绝大多数时候能成功)，从View\ClassWizard\Member Variables里直接生成一个CACComboBox。
4。你可以经过简单修改使之成为具有其他类似功能(自动填写？？)的组合框。
由于时间仓促，没有写详细的注释。感兴趣的朋友请等几天后向我索要。联系方法：
代码如下：
file://-----------------------------------------------------------------------------
// File: ACComboBox.h
//
// Desc:
// 根据用户在编辑框里已经输入的单词，从组合框的列表选项过滤出匹配的项，并使用下拉列表显示出来以供用户选择
//
// Copyright (c) 2001 EagleFly Studio.
//
// Original Author: Zhengpeng.Lan
// Author:
//
// Create Time: 2001/10/10
// Modify Time: 2001/10/11
//
file://-----------------------------------------------------------------------------
#if !defined(AFX_ACCOMBOBOX_H__81CBBD04_3955_4076_A688_74D3EA9730D9__INCLUDED_)
#define AFX_ACCOMBOBOX_H__81CBBD04_3955_4076_A688_74D3EA9730D9__INCLUDED_
#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000
#include "afxtempl.h"
// ACComboBox.h : header file
//
class CACComboBox;
/////////////////////////////////////////////////////////////////////////////
// CWndForACComboBox window
typedef struct
{
int nid;
CString strDepict;
}CInfoForACComboBox;
typedef CArray<CInfoForACComboBox,CInfoForACComboBox &> CInfoForACComboBoxArray;
class CWndForACComboBox : public CWnd
{
friend CACComboBox;
private:
// Construction
LPCTSTR lpWndCls;
// Construction
public:
CWndForACComboBox();
// Attributes
public:
CComboBox * m_pComboBox;
int m_nMaxCount;
CInfoForACComboBoxArray m_aInfo;
int m_nMousePos;
int m_nBeginShow;
inline void RemoveAll()
{
m_aInfo.RemoveAll();
CWnd::SetScrollRange(SB_VERT,0,0);
}
inline void Add(CInfoForACComboBox &info)
{
m_aInfo.Add(info);
}
inline int GetSize()
{
return m_aInfo.GetSize();
}
inline void ShowList()
{
if(IsWindow(GetSafeHwnd()))
{
ShowWindow(SW_SHOWNOACTIVATE);
}
}
// Operations
public:
// Overrides
// ClassWizard generated virtual function overrides
file://{{AFX_VIRTUAL(CWndForACComboBox)
public:
virtual BOOL Create(CComboBox * pWnd);
file://}}AFX_VIRTUAL
// Implementation
public:
virtual ~CWndForACComboBox();
// Generated message map functions
protected:
file://{{AFX_MSG(CWndForACComboBox)
afx_msg void OnDestroy();
afx_msg void OnPaint();
afx_msg void OnKeyDown(UINT nChar, UINT nRepCnt, UINT nFlags);
afx_msg void OnLButtonUp(UINT nFlags, CPoint point);
afx_msg BOOL OnMouseWheel(UINT nFlags, short zDelta, CPoint pt);
afx_msg void OnKillFocus(CWnd* pNewWnd);
afx_msg void OnMouseMove(UINT nFlags, CPoint point);
afx_msg void OnVScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar);
file://}}AFX_MSG
DECLARE_MESSAGE_MAP()
};
/////////////////////////////////////////////////////////////////////////////
// CACComboBox window
class CACComboBox : public CComboBox
{
private:
CEdit* m_pEdit;
// Construction
public:
CACComboBox();
// Attributes
public:
CWndForACComboBox m_wndList;
inline void WindowMove(void)
{
if(IsWindow(m_wndList.GetSafeHwnd()))
m_wndList.Invalidate(FALSE);
}
// Operations
public:
virtual void HandleCompletion();
// Overrides
// ClassWizard generated virtual function overrides
file://{{AFX_VIRTUAL(CACComboBox)
protected:
virtual BOOL OnCommand(WPARAM wParam, LPARAM lParam);
virtual void PreSubclassWindow();
file://}}AFX_VIRTUAL
// Implementation
public:
virtual ~CACComboBox();
// Generated message map functions
protected:
file://{{AFX_MSG(CACComboBox)
afx_msg void OnKillfocus();
afx_msg void OnSelchange();
file://}}AFX_MSG
DECLARE_MESSAGE_MAP()
};
/////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////////////////////////////////////
file://{{AFX_INSERT_LOCATION}}
// Microsoft Visual C++ will insert additional declarations immediately before the previous line.
#endif // !defined(AFX_ACCOMBOBOX_H__81CBBD04_3955_4076_A688_74D3EA9730D9__INCLUDED_)
file://-----------------------------------------------------------------------------
// File: ACComboBox.cpp
//
// Desc:
// 根据用户在编辑框里已经输入的单词，从组合框的列表选项过滤出匹配的项，并使用下拉列表显示出来以供用户选择
//
// Copyright (c) 2001 EagleFly Studio.
//
// Original Author: Zhengpeng.Lan
// Author:
//
// Create Time: 2001/10/10
// Modify Time: 2001/10/11
//
file://-----------------------------------------------------------------------------
#include "stdafx.h"
#include "ACComboBox.h"
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif
/////////////////////////////////////////////////////////////////////////////
// CACComboBox
CACComboBox::CACComboBox()
:CComboBox()
{
m_pEdit = NULL;
}
CACComboBox::~CACComboBox()
{
if(m_pEdit)
delete m_pEdit;
}
BEGIN_MESSAGE_MAP(CACComboBox, CComboBox)
file://{{AFX_MSG_MAP(CACComboBox)
ON_CONTROL_REFLECT(CBN_KILLFOCUS, OnKillfocus)
ON_CONTROL_REFLECT(CBN_SELCHANGE, OnSelchange)
file://}}AFX_MSG_MAP
END_MESSAGE_MAP()
/////////////////////////////////////////////////////////////////////////////
// CACComboBox message handlers
/////////////////////////////////////////////////////////////////////////////
// CWndForACComboBox
CWndForACComboBox::CWndForACComboBox()
:CWnd()
{
lpWndCls = AfxRegisterWndClass(0);
m_pComboBox = NULL;
m_nMaxCount = 8;
m_aInfo.SetSize(0,8);
m_nMousePos = -1;
m_nBeginShow = 0;
}
CWndForACComboBox::~CWndForACComboBox()
{
}
BEGIN_MESSAGE_MAP(CWndForACComboBox, CWnd)
file://{{AFX_MSG_MAP(CWndForACComboBox)
ON_WM_DESTROY()
ON_WM_PAINT()
ON_WM_KEYDOWN()
ON_WM_LBUTTONUP()
ON_WM_MOUSEWHEEL()
ON_WM_KILLFOCUS()
ON_WM_MOUSEMOVE()
ON_WM_VSCROLL()
file://}}AFX_MSG_MAP
END_MESSAGE_MAP()
/////////////////////////////////////////////////////////////////////////////
// CWndForACComboBox message handlers
BOOL CWndForACComboBox::Create(CComboBox * pWnd)
{
ASSERT(pWnd);
CRect rect;
CWnd * pParentWnd = pWnd->GetParent();
pWnd->GetWindowRect(&rect);
// pParentWnd->ScreenToClient(&rect);
BOOL bRet = CWnd::CreateEx( WS_EX_TOPMOST | WS_EX_TOOLWINDOW, lpWndCls, NULL, WS_POPUP | WS_VSCROLL, rect.left, rect.top, rect.Width(), rect.Height(),
pParentWnd->GetSafeHwnd(), NULL, NULL);
if(bRet)
SetOwner(pParentWnd);
m_pComboBox = pWnd;
return bRet;
}
void CWndForACComboBox::OnDestroy()
{
CWnd::OnDestroy();
m_aInfo.RemoveAll();
}
void CWndForACComboBox::OnPaint()
{
CRect rect;
CFont * pFont;
LOGFONT logFont;
if(m_pComboBox)
{
ASSERT(::IsWindow(m_pComboBox->GetSafeHwnd()));
CWnd * pParentWnd = m_pComboBox->GetParent();
m_pComboBox->GetWindowRect(&rect);
pFont = pParentWnd->GetFont();
ASSERT(pFont);
pFont->GetLogFont(&logFont);
if(logFont.lfHeight < 0) logFont.lfHeight = -logFont.lfHeight;
if(m_aInfo.GetSize() > m_nMaxCount)
{
logFont.lfWidth = m_nMaxCount * logFont.lfHeight;
}
else
{
logFont.lfWidth = m_aInfo.GetSize() * logFont.lfHeight;
}
if(logFont.lfWidth + rect.bottom > ::GetSystemMetrics(SM_CYSCREEN))
{
rect.bottom = rect.top;
rect.top = rect.bottom - logFont.lfWidth - 2;
if(rect.top < 0)
rect.top = 0;
}
else
{
rect.top = rect.bottom;
rect.bottom = rect.top + logFont.lfWidth + 2;
}
rect.right = rect.left + m_pComboBox->GetDroppedWidth();
// pParentWnd->ScreenToClient(&rect);
MoveWindow(&rect);
if(rect.Height() < m_aInfo.GetSize() * logFont.lfHeight)
{
TRACE("%d %d\r\n",rect.Height(),m_aInfo.GetSize() * logFont.lfHeight);
SCROLLINFO info;
info.cbSize = sizeof(info);
info.fMask = SIF_PAGE;
info.nPage = rect.Height() / logFont.lfHeight;
CWnd::SetScrollRange(SB_VERT,0,m_aInfo.GetSize() - 1,FALSE);
CWnd::ShowScrollBar(SB_VERT,TRUE);
CWnd::SetScrollInfo(SB_VERT,&info);
}
else
{
CWnd::ShowScrollBar(SB_VERT,FALSE);
}
}
CPaintDC dc(this); // device context for painting
file://dc.FillSolidRect(0,0,rect.Width(),rect.Height(),RGB(255,255,255));
dc.Rectangle(0,0,rect.Width(),rect.Height());
logFont.lfWidth = 1;
dc.SelectObject(pFont);
int m_nBeginShow = CWnd::GetScrollPos(SB_VERT);
for(int i=m_nBeginShow;i<m_aInfo.GetSize() && logFont.lfWidth < rect.Height() - 2;i++)
{
if(i == m_nMousePos)
{
dc.SetBkColor(RGB(0,0,128));
dc.FillSolidRect(1,logFont.lfWidth,rect.Width() - 2,logFont.lfHeight,RGB(0,0,128));
dc.SetTextColor(RGB(255,255,255));
}
else
{
dc.SetBkColor(RGB(255,255,255));
dc.SetTextColor(RGB(0,0,0));
}
dc.TextOut(3,logFont.lfWidth,m_aInfo[i].strDepict);
logFont.lfWidth += logFont.lfHeight;
}
}
void CWndForACComboBox::OnKeyDown(UINT nChar, UINT nRepCnt, UINT nFlags)
{
// TODO: Add your message handler code here and/or call default
CWnd::OnKeyDown(nChar, nRepCnt, nFlags);
}
void CWndForACComboBox::OnLButtonUp(UINT nFlags, CPoint point)
{
CFont * pFont;
LOGFONT logFont;
if(m_pComboBox)
{
pFont = m_pComboBox->GetParent()->GetFont();
pFont->GetLogFont(&logFont);
if(logFont.lfHeight < 0) logFont.lfHeight = -logFont.lfHeight;
m_nMousePos = (point.y - 1) / logFont.lfHeight + CWnd::GetScrollPos(SB_VERT);
if(m_nMousePos >= 0 && m_nMousePos < m_aInfo.GetSize())
m_pComboBox->SetCurSel(m_aInfo[m_nMousePos].nid);
ShowWindow(SW_HIDE);
}
CWnd::OnLButtonUp(nFlags, point);
}
BOOL CWndForACComboBox::OnMouseWheel(UINT nFlags, short zDelta, CPoint pt)
{
// TODO: Add your message handler code here and/or call default
return CWnd::OnMouseWheel(nFlags, zDelta, pt);
}
void CWndForACComboBox::OnKillFocus(CWnd* pNewWnd)
{
CWnd::OnKillFocus(pNewWnd);
if(pNewWnd->GetSafeHwnd() != m_pComboBox->GetSafeHwnd() && pNewWnd->GetSafeHwnd() != GetSafeHwnd() && IsWindow(GetSafeHwnd()))
ShowWindow(SW_HIDE);
}
void CWndForACComboBox::OnMouseMove(UINT nFlags, CPoint point)
{
CFont * pFont;
LOGFONT logFont;
::ShowCursor(TRUE);
if(m_pComboBox)
{
pFont = m_pComboBox->GetParent()->GetFont();
pFont->GetLogFont(&logFont);
if(logFont.lfHeight < 0) logFont.lfHeight = -logFont.lfHeight;
logFont.lfWidth = point.y / logFont.lfHeight + CWnd::GetScrollPos(SB_VERT);
if(logFont.lfWidth != m_nMousePos)
{
m_nMousePos = logFont.lfWidth;
Invalidate();
}
}
CWnd::OnMouseMove(nFlags, point);
}
void CWndForACComboBox::OnVScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar)
{
if(m_aInfo.GetSize() <= 0)
{
CWnd::OnVScroll(nSBCode, nPos, pScrollBar);
return ;
}
switch(nSBCode)
{
// case SB_BOTTOM://Scroll to bottom.
// case SB_ENDSCROLL://End scroll.
case SB_LINEDOWN://Scroll one line down.
{
RECT rc;
LOGFONT logFont;
CFont * pFont;
GetClientRect(&rc);
pFont = m_pComboBox->GetParent()->GetFont();
pFont->GetLogFont(&logFont);
ASSERT(logFont.lfHeight != 0);
if(logFont.lfHeight < 0) logFont.lfHeight = -logFont.lfHeight;
rc.left = (rc.bottom - rc.top) / logFont.lfHeight;
int nPos = GetScrollPos(SB_VERT) + 1;
if(nPos + rc.left <= m_aInfo.GetSize())
{
SetScrollPos(SB_VERT,nPos);
Invalidate();
}
}
break;
case SB_LINEUP://Scroll one line up.
{
int nPos = GetScrollPos(SB_VERT) - 1;
if(nPos >= 0)
{
SetScrollPos(SB_VERT,nPos);
Invalidate();
}
}
break;
case SB_PAGEDOWN://Scroll one page down.
{
RECT rc;
LOGFONT logFont;
CFont * pFont;
GetClientRect(&rc);
pFont = m_pComboBox->GetParent()->GetFont();
pFont->GetLogFont(&logFont);
ASSERT(logFont.lfHeight != 0);
if(logFont.lfHeight < 0) logFont.lfHeight = -logFont.lfHeight;
rc.top = rc.bottom / logFont.lfHeight;
int nPos = GetScrollPos(SB_VERT);
if(nPos < m_aInfo.GetSize() - rc.top)
{
nPos += rc.top;
if(nPos > m_aInfo.GetSize() - rc.top) nPos = m_aInfo.GetSize() - rc.top;
SetScrollPos(SB_VERT,nPos);
Invalidate();
}
}
break;
case SB_PAGEUP://Scroll one page up.
{
RECT rc;
LOGFONT logFont;
CFont * pFont;
GetClientRect(&rc);
pFont = m_pComboBox->GetParent()->GetFont();
pFont->GetLogFont(&logFont);
ASSERT(logFont.lfHeight != 0);
if(logFont.lfHeight < 0) logFont.lfHeight = -logFont.lfHeight;
rc.top = rc.bottom / logFont.lfHeight;
int nPos = GetScrollPos(SB_VERT);
if(nPos > 0)
{
nPos -= rc.top;
if(nPos < 0) nPos = 0;
SetScrollPos(SB_VERT,nPos);
Invalidate();
}
}
break;
// case SB_THUMBPOSITION://Scroll to the absolute position. The current position is provided in nPos.
case SB_THUMBTRACK://Drag scroll box to specified position. The current position is provided in nPos.
{
SetScrollPos(SB_VERT,nPos);
Invalidate();
}
break;
// case SB_TOP://Scroll to top
}
CWnd::OnVScroll(nSBCode, nPos, pScrollBar);
}
void CACComboBox::HandleCompletion()
{
// Make sure we can 'talk' to the edit control
if( m_pEdit == NULL )
{
m_pEdit = new CEdit();
m_pEdit->SubclassWindow(GetDlgItem(1001)->GetSafeHwnd());
}
// Save the state of the edit control
CString text,bestText;
CInfoForACComboBox info;
int n = GetCount();
m_wndList.RemoveAll();
m_pEdit->GetWindowText(text);
CPoint ptCaret = m_pEdit->GetCaretPos();
// int start,end;
// m_pEdit->GetSel(start,end);
// Perform actual completion
int bestindex = -1;
int bestfrom = INT_MAX;
int from;
for ( int x = 0; x < n; x++ )
{
GetLBText(x,info.strDepict);
info.nid = x;
from = info.strDepict.Find(text);
if(from != -1)
{
m_wndList.Add(info);
if( from != -1 && from < bestfrom )
{
bestindex = x;
bestText = info.strDepict;
bestfrom = from;
}
}
}
if ( bestindex != -1)
{
// Restore the edit control
m_pEdit->SetWindowText(bestText);
m_pEdit->SetSel(text.GetLength(),bestText.GetLength());
m_pEdit->SetCaretPos(ptCaret);
}
if(m_wndList.GetSize() != 0)
{
m_wndList.ShowList();
m_wndList.Invalidate();
}
else
{
m_wndList.ShowWindow(SW_HIDE);
}
}
BOOL CACComboBox::OnCommand(WPARAM wParam, LPARAM lParam)
{
if(HIWORD(wParam) == EN_CHANGE)
{
HandleCompletion();
return TRUE;
}
return CComboBox::OnCommand(wParam, lParam);
}
void CACComboBox::PreSubclassWindow()
{
CComboBox::PreSubclassWindow();
m_wndList.Create(this);
}
void CACComboBox::OnKillfocus()
{
m_wndList.OnKillFocus(GetFocus());
}
void CACComboBox::OnSelchange()
{
m_wndList.ShowWindow(SW_HIDE);
}
