viewscrl.cpp

vc6.0完整版

// 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"

#ifdef AFX_CORE2_SEG
#pragma code_seg(AFX_CORE2_SEG)
#endif

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CScrollView

BEGIN_MESSAGE_MAP(CScrollView, CView)
	//{{AFX_MSG_MAP(CScrollView)
	ON_WM_SIZE()
	ON_WM_HSCROLL()
	ON_WM_VSCROLL()
	ON_WM_MOUSEWHEEL()
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

// Special mapping modes just for CScrollView implementation
#define MM_NONE             0
#define MM_SCALETOFIT       (-1)
	// standard GDI mapping modes are > 0

extern BOOL _afxGotScrollLines; // defined in wincore.cpp

UINT PASCAL _AfxGetMouseScrollLines()
{
	static UINT uCachedScrollLines;

	// if we've already got it and we're not refreshing,
	// return what we've already got

	if (_afxGotScrollLines)
		return uCachedScrollLines;

	// see if we can find the mouse window

	_afxGotScrollLines = TRUE;

	static UINT msgGetScrollLines;
	static WORD nRegisteredMessage;

	if (nRegisteredMessage == 0)
	{
		msgGetScrollLines = ::RegisterWindowMessage(MSH_SCROLL_LINES);
		if (msgGetScrollLines == 0)
			nRegisteredMessage = 1;     // couldn't register!  never try again
		else
			nRegisteredMessage = 2;     // it worked: use it
	}

	if (nRegisteredMessage == 2)
	{
		HWND hwMouseWheel = NULL;
		hwMouseWheel = FindWindow(MSH_WHEELMODULE_CLASS, MSH_WHEELMODULE_TITLE);
		if (hwMouseWheel && msgGetScrollLines)
		{
			uCachedScrollLines = (UINT)
				::SendMessage(hwMouseWheel, msgGetScrollLines, 0, 0);
			return uCachedScrollLines;
		}
	}

	// couldn't use the window -- try system settings
	uCachedScrollLines = 3; // reasonable default
	if (!afxData.bWin4)
	{
		HKEY hKey;
		if (RegOpenKeyEx(HKEY_CURRENT_USER,  _T("Control Panel\\Desktop"),
				0, KEY_QUERY_VALUE, &hKey) == ERROR_SUCCESS)
		{
			TCHAR szData[128];
			DWORD dwKeyDataType;
			DWORD dwDataBufSize = _countof(szData);

			if (RegQueryValueEx(hKey, _T("WheelScrollLines"), NULL, &dwKeyDataType,
					(LPBYTE) &szData, &dwDataBufSize) == ERROR_SUCCESS)
			{
				uCachedScrollLines = _tcstoul(szData, NULL, 10);
			}
			RegCloseKey(hKey);
		}
	}
	else if (!afxData.bWin95)
	{
		::SystemParametersInfo(SPI_GETWHEELSCROLLLINES, 0, &uCachedScrollLines, 0);
	}

	return uCachedScrollLines;
}

/////////////////////////////////////////////////////////////////////////////
// CScrollView construction/destruction

CScrollView::CScrollView()
{
	// Init everything to zero
	AFX_ZERO_INIT_OBJECT(CView);

	m_nMapMode = MM_NONE;
}

CScrollView::~CScrollView()
{
}

/////////////////////////////////////////////////////////////////////////////
// CScrollView painting

void CScrollView::OnPrepareDC(CDC* pDC, CPrintInfo* pInfo)
{
	ASSERT_VALID(pDC);

#ifdef _DEBUG
	if (m_nMapMode == MM_NONE)
	{
		TRACE0("Error: must call SetScrollSizes() or SetScaleToFitSize()");
		TRACE0("\tbefore painting scroll view.\n");
		ASSERT(FALSE);
		return;
	}
#endif //_DEBUG
	ASSERT(m_totalDev.cx >= 0 && m_totalDev.cy >= 0);
	switch (m_nMapMode)
	{
	case MM_SCALETOFIT:
		pDC->SetMapMode(MM_ANISOTROPIC);
		pDC->SetWindowExt(m_totalLog);  // window is in logical coordinates
		pDC->SetViewportExt(m_totalDev);
		if (m_totalDev.cx == 0 || m_totalDev.cy == 0)
			TRACE0("Warning: CScrollView scaled to nothing.\n");
		break;

	default:
		ASSERT(m_nMapMode > 0);
		pDC->SetMapMode(m_nMapMode);
		break;
	}

	CPoint ptVpOrg(0, 0);       // assume no shift for printing
	if (!pDC->IsPrinting())
	{
		ASSERT(pDC->GetWindowOrg() == CPoint(0,0));

		// by default shift viewport origin in negative direction of scroll
		ptVpOrg = -GetDeviceScrollPosition();

		if (m_bCenter)
		{
			CRect rect;
			GetClientRect(&rect);

			// if client area is larger than total device size,
			// override scroll positions to place origin such that
			// output is centered in the window
			if (m_totalDev.cx < rect.Width())
				ptVpOrg.x = (rect.Width() - m_totalDev.cx) / 2;
			if (m_totalDev.cy < rect.Height())
				ptVpOrg.y = (rect.Height() - m_totalDev.cy) / 2;
		}
	}
	pDC->SetViewportOrg(ptVpOrg);

	CView::OnPrepareDC(pDC, pInfo);     // For default Printing behavior
}

/////////////////////////////////////////////////////////////////////////////
// Set mode and scaling/scrolling sizes

void CScrollView::SetScaleToFitSize(SIZE sizeTotal)
{
	// Note: It is possible to set sizeTotal members to negative values to
	//  effectively invert either the X or Y axis.

	ASSERT(m_hWnd != NULL);
	m_nMapMode = MM_SCALETOFIT;     // special internal value
	m_totalLog = sizeTotal;

	// reset and turn any scroll bars off
	if (m_hWnd != NULL && (GetStyle() & (WS_HSCROLL|WS_VSCROLL)))
	{
		SetScrollPos(SB_HORZ, 0);
		SetScrollPos(SB_VERT, 0);
		EnableScrollBarCtrl(SB_BOTH, FALSE);
		ASSERT((GetStyle() & (WS_HSCROLL|WS_VSCROLL)) == 0);
	}

	CRect rectT;
	GetClientRect(rectT);
	m_totalDev = rectT.Size();

	if (m_hWnd != NULL)
	{
		// window has been created, invalidate
		UpdateBars();
		Invalidate(TRUE);
	}
}

const AFX_DATADEF SIZE CScrollView::sizeDefault = {0,0};

void CScrollView::SetScrollSizes(int nMapMode, SIZE sizeTotal,
	const SIZE& sizePage, const SIZE& sizeLine)
{
	ASSERT(sizeTotal.cx >= 0 && sizeTotal.cy >= 0);
	ASSERT(nMapMode > 0);
	ASSERT(nMapMode != MM_ISOTROPIC && nMapMode != MM_ANISOTROPIC);

	int nOldMapMode = m_nMapMode;
	m_nMapMode = nMapMode;
	m_totalLog = sizeTotal;

	//BLOCK: convert logical coordinate space to device coordinates
	{
		CWindowDC dc(NULL);
		ASSERT(m_nMapMode > 0);
		dc.SetMapMode(m_nMapMode);

		// total size
		m_totalDev = m_totalLog;
		dc.LPtoDP((LPPOINT)&m_totalDev);
		m_pageDev = sizePage;
		dc.LPtoDP((LPPOINT)&m_pageDev);
		m_lineDev = sizeLine;
		dc.LPtoDP((LPPOINT)&m_lineDev);
		if (m_totalDev.cy < 0)
			m_totalDev.cy = -m_totalDev.cy;
		if (m_pageDev.cy < 0)
			m_pageDev.cy = -m_pageDev.cy;
		if (m_lineDev.cy < 0)
			m_lineDev.cy = -m_lineDev.cy;
	} // release DC here

	// now adjust device specific sizes
	ASSERT(m_totalDev.cx >= 0 && m_totalDev.cy >= 0);
	if (m_pageDev.cx == 0)
		m_pageDev.cx = m_totalDev.cx / 10;
	if (m_pageDev.cy == 0)
		m_pageDev.cy = m_totalDev.cy / 10;
	if (m_lineDev.cx == 0)
		m_lineDev.cx = m_pageDev.cx / 10;
	if (m_lineDev.cy == 0)
		m_lineDev.cy = m_pageDev.cy / 10;

	if (m_hWnd != NULL)
	{
		// window has been created, invalidate now
		UpdateBars();
		if (nOldMapMode != m_nMapMode)
			Invalidate(TRUE);
	}
}

/////////////////////////////////////////////////////////////////////////////
// Getting information

CPoint CScrollView::GetScrollPosition() const   // logical coordinates
{
	if (m_nMapMode == MM_SCALETOFIT)
	{
		return CPoint(0, 0);    // must be 0,0
	}

	CPoint pt = GetDeviceScrollPosition();
	// pt may be negative if m_bCenter is set

	if (m_nMapMode != MM_TEXT)
	{
		ASSERT(m_nMapMode > 0); // must be set
		CWindowDC dc(NULL);
		dc.SetMapMode(m_nMapMode);
		dc.DPtoLP((LPPOINT)&pt);
	}
	return pt;
}

void CScrollView::ScrollToPosition(POINT pt)    // logical coordinates
{
	ASSERT(m_nMapMode > 0);     // not allowed for shrink to fit
	if (m_nMapMode != MM_TEXT)
	{
		CWindowDC dc(NULL);
		dc.SetMapMode(m_nMapMode);
		dc.LPtoDP((LPPOINT)&pt);
	}

	// now in device coordinates - limit if out of range
	int xMax = GetScrollLimit(SB_HORZ);
	int yMax = GetScrollLimit(SB_VERT);
	if (pt.x < 0)
		pt.x = 0;
	else if (pt.x > xMax)
		pt.x = xMax;
	if (pt.y < 0)
		pt.y = 0;
	else if (pt.y > yMax)
		pt.y = yMax;

	ScrollToDevicePosition(pt);
}

CPoint CScrollView::GetDeviceScrollPosition() const
{
	CPoint pt(GetScrollPos(SB_HORZ), GetScrollPos(SB_VERT));
	ASSERT(pt.x >= 0 && pt.y >= 0);

	if (m_bCenter)
	{
		CRect rect;
		GetClientRect(&rect);

		// if client area is larger than total device size,
		// the scroll positions are overridden to place origin such that
		// output is centered in the window
		// GetDeviceScrollPosition() must reflect this

		if (m_totalDev.cx < rect.Width())
			pt.x = -((rect.Width() - m_totalDev.cx) / 2);
		if (m_totalDev.cy < rect.Height())
			pt.y = -((rect.Height() - m_totalDev.cy) / 2);
	}

	return pt;
}

void CScrollView::GetDeviceScrollSizes(int& nMapMode, SIZE& sizeTotal,
			SIZE& sizePage, SIZE& sizeLine) const
{
	if (m_nMapMode <= 0)
		TRACE0("Warning: CScrollView::GetDeviceScrollSizes returning invalid mapping mode.\n");
	nMapMode = m_nMapMode;
	sizeTotal = m_totalDev;
	sizePage = m_pageDev;
	sizeLine = m_lineDev;
}

void CScrollView::ScrollToDevicePosition(POINT ptDev)
{
	ASSERT(ptDev.x >= 0);
	ASSERT(ptDev.y >= 0);

	// Note: ScrollToDevicePosition can and is used to scroll out-of-range
	//  areas as far as CScrollView is concerned -- specifically in
	//  the print-preview code.  Since OnScrollBy makes sure the range is
	//  valid, ScrollToDevicePosition does not vector through OnScrollBy.

	int xOrig = GetScrollPos(SB_HORZ);
	SetScrollPos(SB_HORZ, ptDev.x);
	int yOrig = GetScrollPos(SB_VERT);
	SetScrollPos(SB_VERT, ptDev.y);
	ScrollWindow(xOrig - ptDev.x, yOrig - ptDev.y);
}

/////////////////////////////////////////////////////////////////////////////
// Other helpers

void CScrollView::FillOutsideRect(CDC* pDC, CBrush* pBrush)
{
	ASSERT_VALID(pDC);
	ASSERT_VALID(pBrush);

	// fill rect outside the image
	CRect rect;
	GetClientRect(rect);
	ASSERT(rect.left == 0 && rect.top == 0);
	rect.left = m_totalDev.cx;
	if (!rect.IsRectEmpty())
		pDC->FillRect(rect, pBrush);    // vertical strip along the side
	rect.left = 0;
	rect.right = m_totalDev.cx;
	rect.top = m_totalDev.cy;
	if (!rect.IsRectEmpty())
		pDC->FillRect(rect, pBrush);    // horizontal strip along the bottom
}

void CScrollView::ResizeParentToFit(BOOL bShrinkOnly)
{
	// adjust parent rect so client rect is appropriate size
	ASSERT(m_nMapMode != MM_NONE);  // mapping mode must be known

	// determine current size of the client area as if no scrollbars present
	CRect rectClient;
	GetWindowRect(rectClient);
	CRect rect = rectClient;
	CalcWindowRect(rect);
	rectClient.left += rectClient.left - rect.left;
	rectClient.top += rectClient.top - rect.top;
	rectClient.right -= rect.right - rectClient.right;
	rectClient.bottom -= rect.bottom - rectClient.bottom;
	rectClient.OffsetRect(-rectClient.left, -rectClient.top);
	ASSERT(rectClient.left == 0 && rectClient.top == 0);

	// determine desired size of the view
	CRect rectView(0, 0, m_totalDev.cx, m_totalDev.cy);
	if (bShrinkOnly)
	{
		if (rectClient.right <= m_totalDev.cx)
			rectView.right = rectClient.right;
		if (rectClient.bottom <= m_totalDev.cy)
			rectView.bottom = rectClient.bottom;
	}
	CalcWindowRect(rectView, CWnd::adjustOutside);
	rectView.OffsetRect(-rectView.left, -rectView.top);
	ASSERT(rectView.left == 0 && rectView.top == 0);
	if (bShrinkOnly)
	{
		if (rectClient.right <= m_totalDev.cx)
			rectView.right = rectClient.right;
		if (rectClient.bottom <= m_totalDev.cy)
			rectView.bottom = rectClient.bottom;
	}

	// dermine and set size of frame based on desired size of view
	CRect rectFrame;
	CFrameWnd* pFrame = GetParentFrame();
	ASSERT_VALID(pFrame);
	pFrame->GetWindowRect(rectFrame);
	CSize size = rectFrame.Size();
	size.cx += rectView.right - rectClient.right;
	size.cy += rectView.bottom - rectClient.bottom;
	pFrame->SetWindowPos(NULL, 0, 0, size.cx, size.cy,
		SWP_NOMOVE|SWP_NOZORDER|SWP_NOACTIVATE);
}

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

void CScrollView::OnSize(UINT nType, int cx, int cy)
{
	CView::OnSize(nType, cx, cy);
	if (m_nMapMode == MM_SCALETOFIT)
	{
		// force recalculation of scale to fit parameters
		SetScaleToFitSize(m_totalLog);
	}
	else
	{
		// UpdateBars() handles locking out recursion
		UpdateBars();
	}
}

/////////////////////////////////////////////////////////////////////////////
// Scrolling Helpers

void CScrollView::CenterOnPoint(CPoint ptCenter) // center in device coords
{
	CRect rect;
	GetClientRect(&rect);           // find size of client window

	int xDesired = ptCenter.x - rect.Width() / 2;
	int yDesired = ptCenter.y - rect.Height() / 2;

	DWORD dwStyle = GetStyle();

	if ((dwStyle & WS_HSCROLL) == 0 || xDesired < 0)
	{
		xDesired = 0;
	}
	else
	{
		int xMax = GetScrollLimit(SB_HORZ);
		if (xDesired > xMax)
			xDesired = xMax;
	}

	if ((dwStyle & WS_VSCROLL) == 0 || yDesired < 0)
	{
		yDesired = 0;
	}
	else
	{
		int yMax = GetScrollLimit(SB_VERT);
		if (yDesired > yMax)
			yDesired = yMax;
	}

	ASSERT(xDesired >= 0);
	ASSERT(yDesired >= 0);

	SetScrollPos(SB_HORZ, xDesired);
	SetScrollPos(SB_VERT, yDesired);
}

/////////////////////////////////////////////////////////////////////////////
// Tie to scrollbars and CWnd behaviour

void CScrollView::GetScrollBarSizes(CSize& sizeSb)
{
	sizeSb.cx = sizeSb.cy = 0;
	DWORD dwStyle = GetStyle();

	if (GetScrollBarCtrl(SB_VERT) == NULL)
	{
		// vert scrollbars will impact client area of this window
		sizeSb.cx = afxData.cxVScroll;
		if (dwStyle & WS_BORDER)
			sizeSb.cx -= CX_BORDER;
	}
	if (GetScrollBarCtrl(SB_HORZ) == NULL)
	{
		// horz scrollbars will impact client area of this window
		sizeSb.cy = afxData.cyHScroll;
		if (dwStyle & WS_BORDER)
			sizeSb.cy -= CY_BORDER;
	}
}

BOOL CScrollView::GetTrueClientSize(CSize& size, CSize& sizeSb)
	// return TRUE if enough room to add scrollbars if needed
{
	CRect rect;
	GetClientRect(&rect);
	ASSERT(rect.top == 0 && rect.left == 0);
	size.cx = rect.right;
	size.cy = rect.bottom;