return nScrollInc;
}
-// Adjust the scrollbars - new version.
+void
+wxScrollHelper::AdjustScrollbar(int orient,
+ int clientSize,
+ int virtSize,
+ int& pixelsPerUnit,
+ int& scrollUnits,
+ int& scrollPosition)
+{
+ // scroll lines per page: if 0, no scrolling is needed
+ int unitsPerPage;
+
+ // check if we need scrollbar in this direction at all
+ if ( pixelsPerUnit == 0 || clientSize >= virtSize )
+ {
+ // scrolling is disabled or unnecessary
+ scrollUnits =
+ scrollPosition = 0;
+ unitsPerPage = 0;
+ }
+ else // might need scrolling
+ {
+ // Round up integer division to catch any "leftover" client space.
+ scrollUnits = (virtSize + pixelsPerUnit - 1) / pixelsPerUnit;
+
+ // Calculate the number of fully scroll units
+ unitsPerPage = clientSize / pixelsPerUnit;
+
+ if (unitsPerPage >= scrollUnits)
+ {
+ // we're big enough to not need scrolling
+ scrollUnits =
+ scrollPosition = 0;
+ unitsPerPage = 0;
+ }
+ else // we do need a scrollbar
+ {
+ if ( unitsPerPage < 1 )
+ unitsPerPage = 1;
+
+ // Correct position if greater than extent of canvas minus
+ // the visible portion of it or if below zero
+ const int posMax = scrollUnits - unitsPerPage;
+ if ( scrollPosition > posMax )
+ scrollPosition = posMax;
+ else if ( scrollPosition < 0 )
+ scrollPosition = 0;
+ }
+ }
+
+ m_win->SetScrollbar(orient, scrollPosition, unitsPerPage, scrollUnits);
+
+ // The amount by which we scroll when paging
+ SetScrollPageSize(orient, unitsPerPage);
+}
+
void wxScrollHelper::AdjustScrollbars()
{
static wxRecursionGuardFlag s_flagReentrancy;
return;
}
- int w = 0, h = 0;
- int oldw, oldh;
-
int oldXScroll = m_xScrollPosition;
int oldYScroll = m_yScrollPosition;
- // VZ: at least under Windows this loop is useless because when scrollbars
- // [dis]appear we get a WM_SIZE resulting in another call to
- // AdjustScrollbars() anyhow. As it doesn't seem to do any harm I leave
- // it here for now but it would be better to ensure that all ports
- // generate EVT_SIZE when scrollbars [dis]appear, emulating it if
- // necessary, and remove it later
- // JACS: Stop potential infinite loop by limiting number of iterations
- int iterationCount = 0;
- const int iterationMax = 5;
- do
+ // we may need to readjust the scrollbars several times as enabling one of
+ // them reduces the area available for the window contents and so can make
+ // the other scrollbar necessary now although it wasn't necessary before
+ //
+ // VZ: normally this loop should be over in at most 2 iterations, I don't
+ // know why do we need 5 of them
+ for ( int iterationCount = 0; iterationCount < 5; iterationCount++ )
{
- iterationCount ++;
-
- GetTargetSize(&w, 0);
-
- // scroll lines per page: if 0, no scrolling is needed
- int linesPerPage;
-
- if ( m_xScrollPixelsPerLine == 0 )
- {
- // scrolling is disabled
- m_xScrollLines = 0;
- m_xScrollPosition = 0;
- linesPerPage = 0;
- }
- else // might need scrolling
- {
- // Round up integer division to catch any "leftover" client space.
- const int wVirt = m_targetWindow->GetVirtualSize().GetWidth();
- m_xScrollLines = (wVirt + m_xScrollPixelsPerLine - 1) / m_xScrollPixelsPerLine;
-
- // Calculate page size i.e. number of scroll units you get on the
- // current client window.
- linesPerPage = w / m_xScrollPixelsPerLine;
-
- // Special case. When client and virtual size are very close but
- // the client is big enough, kill scrollbar.
- if ((linesPerPage < m_xScrollLines) && (w >= wVirt)) ++linesPerPage;
-
- if (linesPerPage >= m_xScrollLines)
- {
- // we're big enough to not need scrolling
- linesPerPage =
- m_xScrollLines =
- m_xScrollPosition = 0;
- }
- else // we do need a scrollbar
- {
- if ( linesPerPage < 1 )
- linesPerPage = 1;
-
- // Correct position if greater than extent of canvas minus
- // the visible portion of it or if below zero
- const int posMax = m_xScrollLines - linesPerPage;
- if ( m_xScrollPosition > posMax )
- m_xScrollPosition = posMax;
- else if ( m_xScrollPosition < 0 )
- m_xScrollPosition = 0;
- }
- }
-
- m_win->SetScrollbar(wxHORIZONTAL, m_xScrollPosition,
- linesPerPage, m_xScrollLines);
-
- // The amount by which we scroll when paging
- SetScrollPageSize(wxHORIZONTAL, linesPerPage);
-
- GetTargetSize(0, &h);
-
- if ( m_yScrollPixelsPerLine == 0 )
- {
- // scrolling is disabled
- m_yScrollLines = 0;
- m_yScrollPosition = 0;
- linesPerPage = 0;
- }
- else // might need scrolling
+ wxSize clientSize = GetTargetSize();
+ const wxSize virtSize = m_targetWindow->GetVirtualSize();
+
+ // this block of code tries to work around the following problem: the
+ // window could have been just resized to have enough space to show its
+ // full contents without the scrollbars, but its client size could be
+ // not big enough because it does have the scrollbars right now and so
+ // the scrollbars would remain even though we don't need them any more
+ //
+ // to prevent this from happening, check if we have enough space for
+ // everything without the scrollbars and explicitly disable them then
+ const wxSize availSize = GetSizeAvailableForScrollTarget(
+ m_win->GetSize() - m_win->GetWindowBorderSize());
+ if ( availSize != clientSize )
{
- // Round up integer division to catch any "leftover" client space.
- const int hVirt = m_targetWindow->GetVirtualSize().GetHeight();
- m_yScrollLines = ( hVirt + m_yScrollPixelsPerLine - 1 ) / m_yScrollPixelsPerLine;
-
- // Calculate page size i.e. number of scroll units you get on the
- // current client window.
- linesPerPage = h / m_yScrollPixelsPerLine;
-
- // Special case. When client and virtual size are very close but
- // the client is big enough, kill scrollbar.
- if ((linesPerPage < m_yScrollLines) && (h >= hVirt)) ++linesPerPage;
-
- if (linesPerPage >= m_yScrollLines)
- {
- // we're big enough to not need scrolling
- linesPerPage =
- m_yScrollLines =
- m_yScrollPosition = 0;
- }
- else // we do need a scrollbar
+ if ( availSize.x >= virtSize.x && availSize.y >= virtSize.y )
{
- if ( linesPerPage < 1 )
- linesPerPage = 1;
-
- // Correct position if greater than extent of canvas minus
- // the visible portion of it or if below zero
- const int posMax = m_yScrollLines - linesPerPage;
- if ( m_yScrollPosition > posMax )
- m_yScrollPosition = posMax;
- else if ( m_yScrollPosition < 0 )
- m_yScrollPosition = 0;
+ // this will be enough to make the scrollbars disappear below
+ // and then the client size will indeed become equal to the
+ // full available size
+ clientSize = availSize;
}
}
- m_win->SetScrollbar(wxVERTICAL, m_yScrollPosition,
- linesPerPage, m_yScrollLines);
- // The amount by which we scroll when paging
- SetScrollPageSize(wxVERTICAL, linesPerPage);
+ AdjustScrollbar(wxHORIZONTAL,
+ clientSize.x,
+ virtSize.x,
+ m_xScrollPixelsPerLine,
+ m_xScrollLines,
+ m_xScrollPosition);
+ AdjustScrollbar(wxVERTICAL,
+ clientSize.y,
+ virtSize.y,
+ m_yScrollPixelsPerLine,
+ m_yScrollLines,
+ m_yScrollPosition);
- // If a scrollbar (dis)appeared as a result of this, adjust them again.
- oldw = w;
- oldh = h;
- GetTargetSize( &w, &h );
- } while ( (w != oldw || h != oldh) && (iterationCount < iterationMax) );
+ // If a scrollbar (dis)appeared as a result of this, we need to adjust
+ // them again but if the client size didn't change, then we're done
+ if ( GetTargetSize() == clientSize )
+ break;
+ }
#ifdef __WXMOTIF__
// Sorry, some Motif-specific code to implement a backing pixmap
wxPoint pt = dc.GetDeviceOrigin();
#ifdef __WXGTK__
// It may actually be correct to always query
- // the m_sign from the DC here, but I leve the
+ // the m_sign from the DC here, but I leave the
// #ifdef GTK for now.
if (m_win->GetLayoutDirection() == wxLayout_RightToLeft)
dc.SetDeviceOrigin( pt.x + m_xScrollPosition * m_xScrollPixelsPerLine,
projects / wxWidgets.git / blobdiff