logscrollview.cpp

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		// horz scrollbars will impact client area of this window
		size.cy += sizeSb.cy;   // currently on - adjust now
	}

	// return TRUE if enough room
	return (size.cx > sizeSb.cx && size.cy > sizeSb.cy);
}

// helper to return the state of the scrollbars without actually changing
//  the state of the scrollbars
void CLogScrollView::GetScrollBarState(CSize sizeClient, CSize& needSb,
	CSize& sizeRange, CPoint& ptMove, BOOL bInsideClient)
{
	// get scroll bar sizes (the part that is in the client area)
	CSize sizeSb;
	GetScrollBarSizes(sizeSb);

	// enough room to add scrollbars
	sizeRange = m_totalDev - sizeClient;
		// > 0 => need to scroll
	ptMove = GetDeviceScrollPosition();
		// point to move to (start at current scroll pos)

	BOOL bNeedH = sizeRange.cx > 0;
	if (!bNeedH)
		ptMove.x = 0;                       // jump back to origin
	else if (bInsideClient)
		sizeRange.cy += sizeSb.cy;          // need room for a scroll bar

	BOOL bNeedV = sizeRange.cy > 0;
	if (!bNeedV)
		ptMove.y = 0;                       // jump back to origin
	else if (bInsideClient)
		sizeRange.cx += sizeSb.cx;          // need room for a scroll bar

	if (bNeedV && !bNeedH && sizeRange.cx > 0)
	{
		ASSERT(bInsideClient);
		// need a horizontal scrollbar after all
		bNeedH = TRUE;
		sizeRange.cy += sizeSb.cy;
	}

	// if current scroll position will be past the limit, scroll to limit
	if (sizeRange.cx > 0 && ptMove.x >= sizeRange.cx)
		ptMove.x = sizeRange.cx;
	if (sizeRange.cy > 0 && ptMove.y >= sizeRange.cy)
		ptMove.y = sizeRange.cy;

	// now update the bars as appropriate
	needSb.cx = bNeedH;
	needSb.cy = bNeedV;

	// needSb, sizeRange, and ptMove area now all updated
}

void CLogScrollView::UpdateBars()
{
	// UpdateBars may cause window to be resized - ignore those resizings
	if (m_bInsideUpdate)
		return;         // Do not allow recursive calls

	// Lock out recursion
	m_bInsideUpdate = TRUE;

	// update the horizontal to reflect reality
	// NOTE: turning on/off the scrollbars will cause 'OnSize' callbacks
	ASSERT(m_totalDev.cx >= 0 && m_totalDev.cy >= 0);

	CRect rectClient;
	BOOL bCalcClient = TRUE;

	// allow parent to do inside-out layout first
	CWnd* pParentWnd = GetParent();
	if (pParentWnd != NULL)
	{
		// if parent window responds to this message, use just
		//  client area for scroll bar calc -- not "true" client area
		if ((BOOL)pParentWnd->SendMessage(WM_RECALCPARENT, 0,
			(LPARAM)(LPCRECT)&rectClient) != 0)
		{
			// use rectClient instead of GetTrueClientSize for
			//  client size calculation.
			bCalcClient = FALSE;
		}
	}

	CSize sizeClient;
	CSize sizeSb;

	if (bCalcClient)
	{
		// get client rect
		if (!GetTrueClientSize(sizeClient, sizeSb))
		{
			// no room for scroll bars (common for zero sized elements)
			CRect rect;
			GetClientRect(&rect);
			if (rect.right > 0 && rect.bottom > 0)
			{
				// if entire client area is not invisible, assume we have
				//  control over our scrollbars
				EnableScrollBarCtrl(SB_BOTH, FALSE);
			}
			m_bInsideUpdate = FALSE;
			return;
		}
	}
	else
	{
		// let parent window determine the "client" rect
		GetScrollBarSizes(sizeSb);
		sizeClient.cx = rectClient.right - rectClient.left;
		sizeClient.cy = rectClient.bottom - rectClient.top;
	}

	// enough room to add scrollbars
	CSize sizeRange;
	CPoint ptMove;
	CSize needSb;

	// get the current scroll bar state given the true client area
	GetScrollBarState(sizeClient, needSb, sizeRange, ptMove, bCalcClient);
	if (needSb.cx)
		sizeClient.cy -= sizeSb.cy;
	if (needSb.cy)
		sizeClient.cx -= sizeSb.cx;

	// first scroll the window as needed
	ScrollToDevicePosition(ptMove); // will set the scroll bar positions too

	// this structure needed to update the scrollbar page range
	SCROLLINFO info;
	info.fMask = SIF_PAGE|SIF_RANGE;
	info.nMin = 0;

	// now update the bars as appropriate
	EnableScrollBarCtrl(SB_HORZ, needSb.cx);
	if (needSb.cx)
	{
		info.nPage = sizeClient.cx;
		info.nMax = m_totalDev.cx-1;
		if (!SetScrollInfo(SB_HORZ, &info, TRUE))
			SetScrollRange(SB_HORZ, 0, sizeRange.cx, TRUE);
	}
	EnableScrollBarCtrl(SB_VERT, needSb.cy);
	if (needSb.cy)
	{
		info.nPage = sizeClient.cy;
		info.nMax = m_totalDev.cy-1;
		if (!SetScrollInfo(SB_VERT, &info, TRUE))
			SetScrollRange(SB_VERT, 0, sizeRange.cy, TRUE);
	}

	// remove recursion lockout
	m_bInsideUpdate = FALSE;
}

void CLogScrollView::CalcWindowRect(LPRECT lpClientRect, UINT nAdjustType)
{
	if (nAdjustType == adjustOutside)
	{
		// allow for special client-edge style
		::AdjustWindowRectEx(lpClientRect, 0, FALSE, GetExStyle());

		// if the view is being used in-place, add scrollbar sizes
		//  (scollbars should appear on the outside when in-place editing)
		CSize sizeClient(
			lpClientRect->right - lpClientRect->left,
			lpClientRect->bottom - lpClientRect->top);

		CSize sizeRange = m_totalDev - sizeClient;
			// > 0 => need to scroll

		// get scroll bar sizes (used to adjust the window)
		CSize sizeSb;
		GetScrollBarSizes(sizeSb);

		// adjust the window size based on the state
		if (sizeRange.cy > 0)
		{   // vertical scroll bars take up horizontal space
			lpClientRect->right += sizeSb.cx;
		}
		if (sizeRange.cx > 0)
		{   // horizontal scroll bars take up vertical space
			lpClientRect->bottom += sizeSb.cy;
		}
	}
	else
	{
		// call default to handle other non-client areas
		::AdjustWindowRectEx(lpClientRect, GetStyle(), FALSE,
			GetExStyle() & ~(WS_EX_CLIENTEDGE));
	}
}

/////////////////////////////////////////////////////////////////////////////
// CLogScrollView scrolling

void CLogScrollView::OnHScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar)
{
	if (pScrollBar != NULL && pScrollBar->SendChildNotifyLastMsg())
		return;     // eat it

	// ignore scroll bar msgs from other controls
	if (pScrollBar != GetScrollBarCtrl(SB_HORZ))
		return;

	OnScroll(MAKEWORD(nSBCode, -1), nPos);
}

void CLogScrollView::OnVScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar)
{
	if (pScrollBar != NULL && pScrollBar->SendChildNotifyLastMsg())
		return;     // eat it

	// ignore scroll bar msgs from other controls
	if (pScrollBar != GetScrollBarCtrl(SB_VERT))
		return;

	OnScroll(MAKEWORD(-1, nSBCode), nPos);
}

BOOL CLogScrollView::OnScroll(UINT nScrollCode, UINT nPos, BOOL bDoScroll)
{
	// calc new x position
	int x = GetScrollPos(SB_HORZ);
	int xOrig = x;

	switch (LOBYTE(nScrollCode))
	{
	case SB_TOP:
		x = 0;
		break;
	case SB_BOTTOM:
		x = INT_MAX;
		break;
	case SB_LINEUP:
		x -= m_lineDev.cx;
		break;
	case SB_LINEDOWN:
		x += m_lineDev.cx;
		break;
	case SB_PAGEUP:
		x -= m_pageDev.cx;
		break;
	case SB_PAGEDOWN:
		x += m_pageDev.cx;
		break;
	case SB_THUMBTRACK:
		x = nPos;
		break;
	}

	// calc new y position
	int y = GetScrollPos(SB_VERT);
	int yOrig = y;

	switch (HIBYTE(nScrollCode))
	{
	case SB_TOP:
		y = 0;
		break;
	case SB_BOTTOM:
		y = INT_MAX;
		break;
	case SB_LINEUP:
		y -= m_lineDev.cy;
		break;
	case SB_LINEDOWN:
		y += m_lineDev.cy;
		break;
	case SB_PAGEUP:
		y -= m_pageDev.cy;
		break;
	case SB_PAGEDOWN:
		y += m_pageDev.cy;
		break;
	case SB_THUMBTRACK:
		y = nPos;
		break;
	}

	BOOL bResult = OnScrollBy(CSize(x - xOrig, y - yOrig), bDoScroll);
	if (bResult && bDoScroll)
		UpdateWindow();

	return bResult;
}

BOOL CLogScrollView::OnScrollBy(CSize sizeScroll, BOOL bDoScroll)
{
	int xOrig, x;
	int yOrig, y;

	// don't scroll if there is no valid scroll range (ie. no scroll bar)
	CScrollBar* pBar;
	DWORD dwStyle = GetStyle();
	pBar = GetScrollBarCtrl(SB_VERT);
	if ((pBar != NULL && !pBar->IsWindowEnabled()) ||
		(pBar == NULL && !(dwStyle & WS_VSCROLL)))
	{
		// vertical scroll bar not enabled
		sizeScroll.cy = 0;
	}
	pBar = GetScrollBarCtrl(SB_HORZ);
	if ((pBar != NULL && !pBar->IsWindowEnabled()) ||
		(pBar == NULL && !(dwStyle & WS_HSCROLL)))
	{
		// horizontal scroll bar not enabled
		sizeScroll.cx = 0;
	}

	// adjust current x position
	xOrig = x = GetScrollPos(SB_HORZ);
	int xMax = GetScrollLimit(SB_HORZ);
	x += sizeScroll.cx;
	if (x < 0)
		x = 0;
	else if (x > xMax)
		x = xMax;

	// adjust current y position
	yOrig = y = GetScrollPos(SB_VERT);
	int yMax = GetScrollLimit(SB_VERT);
	y += sizeScroll.cy;
	if (y < 0)
		y = 0;
	else if (y > yMax)
		y = yMax;

	// did anything change?
	if (x == xOrig && y == yOrig)
		return FALSE;

	if (bDoScroll)
	{
		// do scroll and update scroll positions
		ScrollWindow(-(x-xOrig), -(y-yOrig));
		if (x != xOrig)
			SetScrollPos(SB_HORZ, x);
		if (y != yOrig)
			SetScrollPos(SB_VERT, y);
	}
	return TRUE;
}

/////////////////////////////////////////////////////////////////////////////
// CLogScrollView diagnostics

#ifdef _DEBUG
void CLogScrollView::Dump(CDumpContext& dc) const
{
	CView::Dump(dc);

	dc << "m_totalLog = " << m_totalLog;
	dc << "\nm_totalDev = " << m_totalDev;
	dc << "\nm_pageDev = " << m_pageDev;
	dc << "\nm_lineDev = " << m_lineDev;
	dc << "\nm_bCenter = " << m_bCenter;
	dc << "\nm_bInsideUpdate = " << m_bInsideUpdate;
	dc << "\nm_nMapMode = ";
	dc << "MM_LOGICAL TWIPS";
	dc << "\n";
}
#endif //_DEBUG

#ifdef AFX_INIT_SEG
#pragma code_seg(AFX_INIT_SEG)
#endif

IMPLEMENT_DYNAMIC(CLogScrollView, CView)

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