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Hello.

In Drawvw.cpp, will CExtScrollBar be utilized?
Or will standard CSrollBar be utilized?
When I click scroll bar, a bar shines for an instant.
Do you do any special thing?

Please follow these steps for improving the source code of your scrollable view window:

1) The scrollbar creation code should be:

    m_wndScrollBarH.m_eSO = CExtScrollBar::__ESO_BOTTOM;
      m_wndScrollBarV.m_eSO = CExtScrollBar::__ESO_RIGHT;
      if( ! m_wndScrollBarV.Create(
                  WS_CHILD|WS_VISIBLE|SBS_VERT|SBS_RIGHTALIGN,
                  CRect(0,0,0,0),
                  this,
                  1
                  )
            )
      {
            ASSERT( FALSE );
            return -1;
      }
      if( ! m_wndScrollBarH.Create(
                  WS_CHILD|WS_VISIBLE|SBS_HORZ|SBS_BOTTOMALIGN,
                  CRect(0,0,0,0),
                  this,
                  2
                  )
            )
      {
            ASSERT( FALSE );
            return -1;
      }
      m_wndScrollBarH.SyncReservedSpace( &m_wndScrollBarV );
      m_wndScrollBarV.SyncReservedSpace( &m_wndScrollBarH );
      RepositionBars( 0, 0xFFFF, 0 );

2) The OnSize(), OnHScroll() and OnVScroll() handler methods should finally invoke the following:

      RepositionBars( 0, 0xFFFF, 0 );

3) A bit better implementation of the CWnd::GetScrollBarCtrl() virtual method (though your current version is OK):

CScrollBar * CSkeViewPPW::GetScrollBarCtrl( int nBar ) const
{
      ASSERT_VALID( this );
      if( m_hWnd == NULL || (! ::IsWindow(m_hWnd) ) )
            return NULL;
      if( nBar == SB_HORZ )
      {
            if( m_wndScrollBarH.GetSafeHwnd() != NULL )
                  return ( const_cast < CExtScrollBar * > ( &m_wndScrollBarH ) );
      }
      else if( nBar == SB_VERT )
      {
            if( m_wndScrollBarV.GetSafeHwnd() != NULL )
            return ( const_cast < CExtScrollBar * > ( &m_wndScrollBarV ) );
      }
      return NULL;
}

4) The CView::OnScroll() and CView::OnScrollBy() virtual methods should be overridden in your view window.

BOOL CSkeViewPPW::OnScroll( UINT nScrollCode, UINT nPos, BOOL bDoScroll /*= TRUE*/ )
{
      ASSERT_VALID( this );
      bDoScroll;
BOOL bRetVal = CScrollView::OnScroll( nScrollCode, nPos, FALSE );
      Invalidate();
      return bRetVal;
}

BOOL CSkeViewPPW::OnScrollBy( CSize sizeScroll, BOOL bDoScroll /*= TRUE*/ )
{
      ASSERT_VALID( this );
      bDoScroll;
INT xOrig, x, yOrig, y, xMax = GetScrollLimit( SB_HORZ ), yMax = GetScrollLimit( SB_VERT );
      xOrig = x = GetScrollPos(SB_HORZ);
      yOrig = y = GetScrollPos(SB_VERT);
DWORD dwStyle = GetStyle();
CScrollBar * pBarH = GetScrollBarCtrl( SB_HORZ ), * pBarV = GetScrollBarCtrl( SB_VERT );
      if(         ( pBarH != NULL && (!pBarH->IsWindowEnabled()) )
            ||    ( pBarH == NULL && (dwStyle&WS_HSCROLL) != 0 )
            )
            sizeScroll.cx = 0;
      if(         ( pBarV != NULL && (!pBarV->IsWindowEnabled()) )
            ||    ( pBarV == NULL && (dwStyle&WS_VSCROLL) != 0 )
            )
            sizeScroll.cy = 0;
      x += sizeScroll.cx;
      if( x < 0 )
            x = 0;
      else if( x > xMax )
            x = xMax;
      y += sizeScroll.cy;
      if( y < 0 )
            y = 0;
      else if( y > yMax )
            y = yMax;
      if( x == xOrig && y == yOrig )
            return FALSE;
      if( x != xOrig )
            SetScrollPos( SB_HORZ, x );
      if( y != yOrig )
            SetScrollPos( SB_VERT, y );
      Invalidate();
      return TRUE;
}

Hello.

I programed it as follows.
However, the scroll bar is displayed, but does not work.


class MT_EXPORT CSkeViewPPW : public CExtPPVW < CScrollView >
{
...........................................

}


CScrollBar * CSkeViewPPW::GetScrollBarCtrl( int nBar ) const
{
ASSERT_VALID( this );
if( m_hWnd == NULL || (! ::IsWindow(m_hWnd) ) )
return NULL;
ASSERT( nBar == SB_HORZ || nBar == SB_VERT );
if( nBar == SB_HORZ )
{
if( m_wndScrollBarH.GetSafeHwnd() != NULL )
return ( const_cast < CExtScrollBar * > ( &m_wndScrollBarH ) );
} // if( nBar == SB_HORZ )
else
{
if( m_wndScrollBarV.GetSafeHwnd() != NULL )
return ( const_cast < CExtScrollBar * > ( &m_wndScrollBarV ) );
} // else from if( nBar == SB_HORZ )
return NULL;
}

void CSkeViewPPW::OnInitialUpdate()
{
    m_wndScrollBarH.m_eSO = CExtScrollBar::__ESO_BOTTOM;
m_wndScrollBarV.m_eSO = CExtScrollBar::__ESO_RIGHT;
if( ! m_wndScrollBarV.Create(
WS_CHILD|WS_VISIBLE|SBS_VERT|SBS_RIGHTALIGN,
CRect(0,0,0,0),
this,
1
)
)
{
ASSERT( FALSE );
        return;
}
if( ! m_wndScrollBarH.Create(
WS_CHILD|WS_VISIBLE|SBS_HORZ|SBS_BOTTOMALIGN,
CRect(0,0,0,0),
this,
2
)
)
{
ASSERT( FALSE );
        return;
}
m_wndScrollBarH.SyncReservedSpace( &m_wndScrollBarV );
m_wndScrollBarV.SyncReservedSpace( &m_wndScrollBarH );

    CSize sizeTotal(1,1);
    CSize Page(100,50);
    CSize Line(10,10);
    SetScrollSizes(MM_TEXT, sizeTotal /*,Page,Line*/ );

}

void CSkeViewPPW::OnHScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar)
{
    pScrollBar = GetScrollBarCtrl( SB_HORZ );
    CExtPPVW < CScrollView >::OnHScroll(nSBCode, nPos, pScrollBar);

    Invalidate();
    UpdateWindow();
}

void CSkeViewPPW::OnVScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar)
{
    pScrollBar = GetScrollBarCtrl( SB_VERT );
    CExtPPVW < CScrollView >::OnVScroll(nSBCode, nPos, pScrollBar);

    Invalidate();
    UpdateWindow();
}

Thank you

The view window in this sample application is based on the CExtSplitterWnd splitter window which uses CExtScrollBar scroll bars controls instead of MFC’s CScrollBar. You can use a CExtScrollBar control independently of any Prof-UIS classes. This is simply a repainted version of CScrollBar which also supports themed animations.