C++ wxNavigationKeyEvent::IsFromTab方法代码示例

//.........这里部分代码省略.........

    // we should start from the first/last control and not from the one which
    // had focus the last time if we're propagating the event downwards because
    // for our parent we look like a single control
    if ( goingDown )
    {
        // just to be sure it's not used (normally this is not necessary, but
        // doesn't hurt neither)
        m_winLastFocused = NULL;

        // start from first or last depending on where we're going
        node = forward ? children.GetFirst() : children.GetLast();
    }
    else // going up
    {
        // try to find the child which has the focus currently

        // the event emitter might have done this for us
        wxWindow *winFocus = event.GetCurrentFocus();

        // but if not, we might know where the focus was ourselves
        if (!winFocus)
            winFocus = m_winLastFocused;

        // if still no luck, do it the hard way
        if (!winFocus)
            winFocus = wxWindow::FindFocus();

        if ( winFocus )
        {
#if defined(__WXMSW__) && wxUSE_RADIOBTN
            // If we are in a radio button group, start from the first item in the
            // group
            if ( event.IsFromTab() && wxIsKindOf(winFocus, wxRadioButton ) )
                winFocus = wxGetFirstButtonInGroup((wxRadioButton*)winFocus);
#endif // __WXMSW__
            // ok, we found the focus - now is it our child?
            start_node = children.Find( winFocus );
        }

        if ( !start_node && m_winLastFocused )
        {
            // window which has focus isn't our child, fall back to the one
            // which had the focus the last time
            start_node = children.Find( m_winLastFocused );
        }

        // if we still didn't find anything, we should start with the first one
        if ( !start_node )
        {
            start_node = children.GetFirst();
        }

        // and the first child which we can try setting focus to is the next or
        // the previous one
        node = forward ? start_node->GetNext() : start_node->GetPrevious();
    }

    // we want to cycle over all elements passing by NULL
    for ( ;; )
    {
        // don't go into infinite loop
        if ( start_node && node && node == start_node )
            break;

        // Have we come to the last or first item on the panel?