帶滾動條的對話框類

在codeproject上看到了個有滾動條的對話框DEMO,原文http://www.codeproject.com/KB/dialog/scroll_dialog.aspx，不過是用SDK寫的，爲了在MFC下使用方便，把它改寫成了類CScrollDialog，使用時把自己的對話框從CScrollDialog類繼承，並把自己對話框類代碼中的CDialog都替換爲CScrollDialog即可。代碼如下：

ScrollDialog.h文件

// ScrollDialog.h: interface for the CScrollDialog class. // ////////////////////////////////////////////////////////////////////// #if !defined(AFX_SCROLLDIALOG_H__DE1B196D_7CF8_4834_A2A5_0AEDAE400AE4__INCLUDED_) #define AFX_SCROLLDIALOG_H__DE1B196D_7CF8_4834_A2A5_0AEDAE400AE4__INCLUDED_ #if _MSC_VER > 1000 #pragma once #endif // _MSC_VER > 1000 #define ARRAYSIZE(a) sizeof(a)/sizeof(a[0]) ///////////////////////////////////////////////////////////////////////////// // CScrollDialog dialog class CScrollDialog : public CDialog { // Construction public: CScrollDialog(); // standard constructor CScrollDialog(UINT nIDTemplate, CWnd* pParentWnd = NULL); CScrollDialog(LPCTSTR lpszTemplateName, CWnd* pParentWnd = NULL); virtual ~CScrollDialog(); // Overrides // ClassWizard generated virtual function overrides //{{AFX_VIRTUAL(CScrollDialog) protected: virtual void DoDataExchange(CDataExchange* pDX); // DDX/DDV support //}}AFX_VIRTUAL // Implementation protected: // Generated message map functions //{{AFX_MSG(CScrollDialog) virtual BOOL OnInitDialog(); afx_msg void OnSize(UINT nType, int cx, int cy); afx_msg void OnHScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar); afx_msg void OnVScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar); //}}AFX_MSG DECLARE_MESSAGE_MAP() protected: void ScrollClient(int nBar, int nPos); void HVScrool(int nBar, UINT nSBCode); int GetScrollPos(int nBar, UINT nSBCode); }; #endif // !defined(AFX_SCROLLDIALOG_H__DE1B196D_7CF8_4834_A2A5_0AEDAE400AE4__INCLUDED_)

ScrollDialog.cpp文件

// ScrollDialog.cpp : implementation file // #include "stdafx.h" #include "ScrollDialog.h" #ifdef _DEBUG #define new DEBUG_NEW #undef THIS_FILE static char THIS_FILE[] = __FILE__; #endif ///////////////////////////////////////////////////////////////////////////// // CScrollDialog dialog CScrollDialog::CScrollDialog() : CDialog() { } CScrollDialog::CScrollDialog(UINT nIDTemplate, CWnd* pParentWnd) : CDialog(nIDTemplate, pParentWnd) { } CScrollDialog::CScrollDialog(LPCTSTR lpszTemplateName, CWnd* pParentWnd) : CDialog(lpszTemplateName, pParentWnd) { } CScrollDialog::~CScrollDialog() { } void CScrollDialog::DoDataExchange(CDataExchange* pDX) { CDialog::DoDataExchange(pDX); //{{AFX_DATA_MAP(CScrollDialog) // NOTE: the ClassWizard will add DDX and DDV calls here //}}AFX_DATA_MAP } BEGIN_MESSAGE_MAP(CScrollDialog, CDialog) //{{AFX_MSG_MAP(CScrollDialog) ON_WM_SIZE() ON_WM_HSCROLL() ON_WM_VSCROLL() //}}AFX_MSG_MAP END_MESSAGE_MAP() ///////////////////////////////////////////////////////////////////////////// // CScrollDialog message handlers BOOL CScrollDialog::OnInitDialog() { CDialog::OnInitDialog(); // TODO: Add extra initialization here CRect rc; GetClientRect(&rc); const SIZE sz = { rc.right - rc.left, rc.bottom - rc.top }; SCROLLINFO si; si.cbSize = sizeof(SCROLLINFO); si.fMask = SIF_PAGE | SIF_POS | SIF_RANGE; si.nPos = si.nMin = 1; si.nMax = sz.cx; si.nPage = sz.cx; SetScrollInfo(SB_HORZ, &si, FALSE); si.nMax = sz.cy; si.nPage = sz.cy; SetScrollInfo(SB_VERT, &si, FALSE); return TRUE; // return TRUE unless you set the focus to a control // EXCEPTION: OCX Property Pages should return FALSE } void CScrollDialog::OnSize(UINT nType, int cx, int cy) { CDialog::OnSize(nType, cx, cy); // TODO: Add your message handler code here if(nType != SIZE_RESTORED && nType != SIZE_MAXIMIZED) return; SCROLLINFO si; si.cbSize = sizeof(SCROLLINFO); const int bar[] = { SB_HORZ, SB_VERT }; const int page[] = { cx, cy }; for(size_t i = 0; i < ARRAYSIZE(bar); ++i) { si.fMask = SIF_PAGE; si.nPage = page[i]; SetScrollInfo(bar[i], &si, TRUE); si.fMask = SIF_RANGE | SIF_POS; GetScrollInfo(bar[i], &si); const int maxScrollPos = si.nMax - (page[i] - 1); const bool needToScroll = (si.nPos != si.nMin && si.nPos == maxScrollPos) || (nType == SIZE_MAXIMIZED); if(needToScroll) { ScrollClient(bar[i], si.nPos); } } } void CScrollDialog::OnHScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar) { // TODO: Add your message handler code here and/or call default HVScrool(SB_HORZ,nSBCode); CDialog::OnHScroll(nSBCode, nPos, pScrollBar); } void CScrollDialog::OnVScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar) { // TODO: Add your message handler code here and/or call default HVScrool(SB_VERT,nSBCode); CDialog::OnVScroll(nSBCode, nPos, pScrollBar); } void CScrollDialog::ScrollClient(int nBar, int nPos) { static int s_prevx = 1; static int s_prevy = 1; int cx = 0; int cy = 0; int& delta = (nBar == SB_HORZ ? cx : cy); int& prev = (nBar == SB_HORZ ? s_prevx : s_prevy); delta = prev - nPos; prev = nPos; if(cx || cy) { ScrollWindow(cx, cy, NULL, NULL); } } void CScrollDialog::HVScrool(int nBar, UINT nSBCode) { const int scrollPos = GetScrollPos(nBar,nSBCode); if(scrollPos == -1) return; SetScrollPos(nBar, scrollPos, TRUE); ScrollClient(nBar, scrollPos); } int CScrollDialog::GetScrollPos(int nBar, UINT nSBCode) { SCROLLINFO si; si.cbSize = sizeof(SCROLLINFO); si.fMask = SIF_PAGE | SIF_POS | SIF_RANGE | SIF_TRACKPOS; GetScrollInfo(nBar, &si); const int minPos = si.nMin; const int maxPos = si.nMax - (si.nPage - 1); int result = -1; switch(nSBCode) { case SB_LINEUP /*SB_LINELEFT*/: result = max(si.nPos - 1, minPos); break; case SB_LINEDOWN /*SB_LINERIGHT*/: result = min(si.nPos + 1, maxPos); break; case SB_PAGEUP /*SB_PAGELEFT*/: result = max(si.nPos - (int)si.nPage, minPos); break; case SB_PAGEDOWN /*SB_PAGERIGHT*/: result = min(si.nPos + (int)si.nPage, maxPos); break; case SB_THUMBPOSITION: // do nothing break; case SB_THUMBTRACK: result = si.nTrackPos; break; case SB_TOP /*SB_LEFT*/: result = minPos; break; case SB_BOTTOM /*SB_RIGHT*/: result = maxPos; break; case SB_ENDSCROLL: // do nothing break; } return result; }