void CScrollWnd::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 CXTPPropertyPage::UpdateBars()
{
if (m_totalDev == CSize(0, 0) || !m_bCreated)
return;
// 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;
CSize sizeClient;
CSize sizeSb;
// 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;
}
// 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;
}
