return;
}
- // flush all pending repaints before we change m_{x,y}ScrollPosition, as
- // otherwise invalidated area could be updated incorrectly later when
- // ScrollWindow() makes sure they're repainted before scrolling them
- m_targetWindow->Update();
-
- int orient = event.GetOrientation();
- if (orient == wxHORIZONTAL)
- {
- m_xScrollPosition += nScrollInc;
- m_win->SetScrollPos(wxHORIZONTAL, m_xScrollPosition);
- }
- else
- {
- m_yScrollPosition += nScrollInc;
- m_win->SetScrollPos(wxVERTICAL, m_yScrollPosition);
- }
-
bool needsRefresh = false;
int dx = 0,
dy = 0;
+ int orient = event.GetOrientation();
if (orient == wxHORIZONTAL)
{
if ( m_xScrollingEnabled )
}
}
+ if ( !needsRefresh )
+ {
+ // flush all pending repaints before we change m_{x,y}ScrollPosition, as
+ // otherwise invalidated area could be updated incorrectly later when
+ // ScrollWindow() makes sure they're repainted before scrolling them
+ m_targetWindow->Update();
+ }
+
+ if (orient == wxHORIZONTAL)
+ {
+ m_xScrollPosition += nScrollInc;
+ m_win->SetScrollPos(wxHORIZONTAL, m_xScrollPosition);
+ }
+ else
+ {
+ m_yScrollPosition += nScrollInc;
+ m_win->SetScrollPos(wxVERTICAL, m_yScrollPosition);
+ }
+
if ( needsRefresh )
{
m_targetWindow->Refresh(true, GetScrollRect());
int w = 0, h = 0;
GetTargetSize(&w, &h);
- // flush all pending repaints before we change m_{x,y}ScrollPosition, as
- // otherwise invalidated area could be updated incorrectly later when
- // ScrollWindow() makes sure they're repainted before scrolling them
- m_targetWindow->Update();
+ // compute new position:
+ int new_x = m_xScrollPosition;
+ int new_y = m_yScrollPosition;
if ((x_pos != -1) && (m_xScrollPixelsPerLine))
{
- int old_x = m_xScrollPosition;
- m_xScrollPosition = x_pos;
+ new_x = x_pos;
// Calculate page size i.e. number of scroll units you get on the
// current client window
// Correct position if greater than extent of canvas minus
// the visible portion of it or if below zero
- m_xScrollPosition = wxMin( m_xScrollLines-noPagePositions, m_xScrollPosition );
- m_xScrollPosition = wxMax( 0, m_xScrollPosition );
-
- if (old_x != m_xScrollPosition)
- {
- m_win->SetScrollPos( wxHORIZONTAL, m_xScrollPosition );
- m_targetWindow->ScrollWindow( (old_x-m_xScrollPosition)*m_xScrollPixelsPerLine, 0,
- GetScrollRect() );
- }
+ new_x = wxMin( m_xScrollLines-noPagePositions, new_x );
+ new_x = wxMax( 0, new_x );
}
if ((y_pos != -1) && (m_yScrollPixelsPerLine))
{
- int old_y = m_yScrollPosition;
- m_yScrollPosition = y_pos;
+ new_y = y_pos;
// Calculate page size i.e. number of scroll units you get on the
// current client window
// Correct position if greater than extent of canvas minus
// the visible portion of it or if below zero
- m_yScrollPosition = wxMin( m_yScrollLines-noPagePositions, m_yScrollPosition );
- m_yScrollPosition = wxMax( 0, m_yScrollPosition );
+ new_y = wxMin( m_yScrollLines-noPagePositions, new_y );
+ new_y = wxMax( 0, new_y );
+ }
- if (old_y != m_yScrollPosition)
- {
- m_win->SetScrollPos( wxVERTICAL, m_yScrollPosition );
- m_targetWindow->ScrollWindow( 0, (old_y-m_yScrollPosition)*m_yScrollPixelsPerLine,
- GetScrollRect() );
- }
+ if ( new_x == m_xScrollPosition && new_y == m_yScrollPosition )
+ return; // nothing to do, the position didn't change
+
+ // flush all pending repaints before we change m_{x,y}ScrollPosition, as
+ // otherwise invalidated area could be updated incorrectly later when
+ // ScrollWindow() makes sure they're repainted before scrolling them
+ m_targetWindow->Update();
+
+ // update the position and scroll the window now:
+ if (m_xScrollPosition != new_x)
+ {
+ int old_x = m_xScrollPosition;
+ m_xScrollPosition = new_x;
+ m_win->SetScrollPos( wxHORIZONTAL, new_x );
+ m_targetWindow->ScrollWindow( (old_x-new_x)*m_xScrollPixelsPerLine, 0,
+ GetScrollRect() );
+ }
+
+ if (m_yScrollPosition != new_y)
+ {
+ int old_y = m_yScrollPosition;
+ m_yScrollPosition = new_y;
+ m_win->SetScrollPos( wxVERTICAL, new_y );
+ m_targetWindow->ScrollWindow( 0, (old_y-new_y)*m_yScrollPixelsPerLine,
+ GetScrollRect() );
}
}