ecscrolwin.cpp

ecos实时嵌入式操作系统

            else if ( (m_xScrollPosition + nScrollInc) > noPositions )
                nScrollInc = noPositions - m_xScrollPosition; // As +ve as we can go
        }
        else
            m_targetWindow->Refresh();
    }
    else
    {
        if (m_yScrollPixelsPerLine > 0)
        {
            int w, h;
            m_targetWindow->GetClientSize(&w, &h);

            int nMaxHeight = m_yScrollLines*m_yScrollPixelsPerLine;
            int noPositions = (int) ( ((nMaxHeight - h)/(double)m_yScrollPixelsPerLine) + 0.5 );
            if (noPositions < 0)
                noPositions = 0;

            if ( (m_yScrollPosition + nScrollInc) < 0 )
                nScrollInc = -m_yScrollPosition; // As -ve as we can go
            else if ( (m_yScrollPosition + nScrollInc) > noPositions )
                nScrollInc = noPositions - m_yScrollPosition; // As +ve as we can go
        }
        else
            m_targetWindow->Refresh();
    }

    return nScrollInc;
}

// Adjust the scrollbars - new version.
void ecScrolledWindow::AdjustScrollbars()
{
    int w, h;
    m_targetWindow->GetClientSize(&w, &h);

    int oldXScroll = m_xScrollPosition;
    int oldYScroll = m_yScrollPosition;

    if (m_xScrollLines > 0)
    {
        // Calculate page size i.e. number of scroll units you get on the
        // current client window
        int noPagePositions = (int) ( (w/(double)m_xScrollPixelsPerLine) + 0.5 );
        if (noPagePositions < 1) noPagePositions = 1;

        // 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 );

        SetScrollbar(wxHORIZONTAL, m_xScrollPosition, noPagePositions, m_xScrollLines);
        // The amount by which we scroll when paging
        SetScrollPageSize(wxHORIZONTAL, noPagePositions);
    }
    else
    {
        m_xScrollPosition = 0;
        SetScrollbar (wxHORIZONTAL, 0, 0, 0, FALSE);
    }

    if (m_yScrollLines > 0)
    {
        // Calculate page size i.e. number of scroll units you get on the
        // current client window
        int noPagePositions = (int) ( (h/(double)m_yScrollPixelsPerLine) + 0.5 );
        if (noPagePositions < 1) noPagePositions = 1;

        // 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 );

        SetScrollbar(wxVERTICAL, m_yScrollPosition, noPagePositions, m_yScrollLines);
        // The amount by which we scroll when paging
        SetScrollPageSize(wxVERTICAL, noPagePositions);
    }
    else
    {
        m_yScrollPosition = 0;
        SetScrollbar (wxVERTICAL, 0, 0, 0, FALSE);
    }

    if (oldXScroll != m_xScrollPosition)
    {
       if (m_xScrollingEnabled)
            m_targetWindow->ScrollWindow( m_xScrollPixelsPerLine * (oldXScroll-m_xScrollPosition), 0, (const wxRect *) NULL );
       else
            m_targetWindow->Refresh();
    }

    if (oldYScroll != m_yScrollPosition)
    {
        if (m_yScrollingEnabled)
            m_targetWindow->ScrollWindow( 0, m_yScrollPixelsPerLine * (oldYScroll-m_yScrollPosition), (const wxRect *) NULL );
        else
            m_targetWindow->Refresh();
    }
}

// Override this function if you don't want to have ecScrolledWindow
// automatically change the origin according to the scroll position.
void ecScrolledWindow::PrepareDC(wxDC& dc)
{
    dc.SetDeviceOrigin( -m_xScrollPosition * m_xScrollPixelsPerLine,
                        -m_yScrollPosition * m_yScrollPixelsPerLine );
    dc.SetUserScale( m_scaleX, m_scaleY );
}

#if WXWIN_COMPATIBILITY
void ecScrolledWindow::GetScrollUnitsPerPage (int *x_page, int *y_page) const
{
      *x_page = GetScrollPageSize(wxHORIZONTAL);
      *y_page = GetScrollPageSize(wxVERTICAL);
}

void ecScrolledWindow::CalcUnscrolledPosition(int x, int y, float *xx, float *yy) const
{
    if ( xx )
        *xx = (float)(x + m_xScrollPosition * m_xScrollPixelsPerLine);
    if ( yy )
        *yy = (float)(y + m_yScrollPosition * m_yScrollPixelsPerLine);
}
#endif // WXWIN_COMPATIBILITY

void ecScrolledWindow::GetScrollPixelsPerUnit (int *x_unit, int *y_unit) const
{
    if ( x_unit )
        *x_unit = m_xScrollPixelsPerLine;
    if ( y_unit )
        *y_unit = m_yScrollPixelsPerLine;
}

int ecScrolledWindow::GetScrollPageSize(int orient) const
{
    if ( orient == wxHORIZONTAL )
        return m_xScrollLinesPerPage;
    else
        return m_yScrollLinesPerPage;
}

void ecScrolledWindow::SetScrollPageSize(int orient, int pageSize)
{
    if ( orient == wxHORIZONTAL )
        m_xScrollLinesPerPage = pageSize;
    else
        m_yScrollLinesPerPage = pageSize;
}

/*
 * Scroll to given position (scroll position, not pixel position)
 */
void ecScrolledWindow::Scroll( int x_pos, int y_pos )
{
    if (!m_targetWindow)
        return;

    if (((x_pos == -1) || (x_pos == m_xScrollPosition)) &&
        ((y_pos == -1) || (y_pos == m_yScrollPosition))) return;

    int w, h;
    m_targetWindow->GetClientSize(&w, &h);

    if ((x_pos != -1) && (m_xScrollPixelsPerLine))
    {
        int old_x = m_xScrollPosition;
        m_xScrollPosition = x_pos;

        // Calculate page size i.e. number of scroll units you get on the
        // current client window
        int noPagePositions = (int) ( (w/(double)m_xScrollPixelsPerLine) + 0.5 );
        if (noPagePositions < 1) noPagePositions = 1;

        // 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_targetWindow->SetScrollPos( wxHORIZONTAL, m_xScrollPosition, TRUE );
            m_targetWindow->ScrollWindow( (old_x-m_xScrollPosition)*m_xScrollPixelsPerLine, 0 );
        }
    }
    if ((y_pos != -1) && (m_yScrollPixelsPerLine))
    {
        int old_y = m_yScrollPosition;
        m_yScrollPosition = y_pos;

        // Calculate page size i.e. number of scroll units you get on the
        // current client window
        int noPagePositions = (int) ( (h/(double)m_yScrollPixelsPerLine) + 0.5 );
        if (noPagePositions < 1) noPagePositions = 1;

        // 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 );
        
        if (old_y != m_yScrollPosition) {
            m_targetWindow->SetScrollPos( wxVERTICAL, m_yScrollPosition, TRUE );
            m_targetWindow->ScrollWindow( 0, (old_y-m_yScrollPosition)*m_yScrollPixelsPerLine );
        }
    }

#ifdef __WXMAC__
    m_targetWindow->MacUpdateImmediately();
#endif
}

void ecScrolledWindow::EnableScrolling (bool x_scroll, bool y_scroll)
{
    m_xScrollingEnabled = x_scroll;
    m_yScrollingEnabled = y_scroll;
}

void ecScrolledWindow::GetVirtualSize (int *x, int *y) const
{
    if ( x )
        *x = m_xScrollPixelsPerLine * m_xScrollLines;
    if ( y )
        *y = m_yScrollPixelsPerLine * m_yScrollLines;
}

// Where the current view starts from
void ecScrolledWindow::GetViewStart (int *x, int *y) const
{
    if ( x )
        *x = m_xScrollPosition;
    if ( y )
        *y = m_yScrollPosition;
}

void ecScrolledWindow::CalcScrolledPosition(int x, int y, int *xx, int *yy) const
{
    if ( xx )
        *xx = x - m_xScrollPosition * m_xScrollPixelsPerLine;
    if ( yy )
        *yy = y - m_yScrollPosition * m_yScrollPixelsPerLine;
}

void ecScrolledWindow::CalcUnscrolledPosition(int x, int y, int *xx, int *yy) const
{
    if ( xx )
        *xx = x + m_xScrollPosition * m_xScrollPixelsPerLine;
    if ( yy )
        *yy = y + m_yScrollPosition * m_yScrollPixelsPerLine;
}

// ----------------------------------------------------------------------------
// event handlers
// ----------------------------------------------------------------------------

// Default OnSize resets scrollbars, if any
void ecScrolledWindow::OnSize(wxSizeEvent& WXUNUSED(event))
{
#if wxUSE_CONSTRAINTS
    if (GetAutoLayout())
        Layout();
#endif

    AdjustScrollbars();
}

// This calls OnDraw, having adjusted the origin according to the current
// scroll position
void ecScrolledWindow::OnPaint(wxPaintEvent& WXUNUSED(event))
{
    wxPaintDC dc(this);
    PrepareDC(dc);

    OnDraw(dc);
}

// kbd handling: notice that we use OnChar() and not OnKeyDown() for
// compatibility here - if we used OnKeyDown(), the programs which process
// arrows themselves in their OnChar() would never get the message and like
// this they always have the priority
void ecScrolledWindow::OnChar(wxKeyEvent& event)
{
    int stx, sty,       // view origin
        szx, szy,       // view size (total)
        clix, cliy;     // view size (on screen)

    ViewStart(&stx, &sty);
    GetClientSize(&clix, &cliy);
    GetVirtualSize(&szx, &szy);

    if( m_xScrollPixelsPerLine )
    {
        clix /= m_xScrollPixelsPerLine;
        szx /= m_xScrollPixelsPerLine;
    }
    else
    {
        clix = 0;
        szx = -1;
    }
    if( m_yScrollPixelsPerLine )
    {
        cliy /= m_yScrollPixelsPerLine;
        szy /= m_yScrollPixelsPerLine;
    }
    else
    {
        cliy = 0;
        szy = -1;
    }

    int dsty;
    switch ( event.KeyCode() )
    {
        case WXK_PAGEUP:
        case WXK_PRIOR:
            dsty = sty - (5 * cliy / 6);
            Scroll(-1, (dsty == -1) ? 0 : dsty);
            break;

        case WXK_PAGEDOWN:
        case WXK_NEXT:
            Scroll(-1, sty + (5 * cliy / 6));
            break;

        case WXK_HOME:
            Scroll(0, event.ControlDown() ? 0 : -1);
            break;

        case WXK_END:
            Scroll(szx - clix, event.ControlDown() ? szy - cliy : -1);
            break;

        case WXK_UP:
            Scroll(-1, sty - 1);
            break;

        case WXK_DOWN:
            Scroll(-1, sty + 1);
            break;

        case WXK_LEFT:
            Scroll(stx - 1, -1);
            break;

        case WXK_RIGHT:
            Scroll(stx + 1, -1);
            break;

        default:
            // not for us
            event.Skip();
    }
}
#endif
// ecUSE_OWN_SCROLLED_WINDOW