renderlistbox.cpp

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    const UChar* string = itemText.characters();
    TextRun textRun(string, length, 0, 0, 0, itemStyle->direction() == RTL, itemStyle->unicodeBidi() == Override, false, false);

    // Draw the item text
    if (itemStyle->visibility() != HIDDEN)
        paintInfo.context->drawBidiText(itemFont, textRun, r.location());
}

void RenderListBox::paintItemBackground(PaintInfo& paintInfo, int tx, int ty, int listIndex)
{
    HTMLSelectElement* select = static_cast<HTMLSelectElement*>(node());
    const Vector<HTMLElement*>& listItems = select->listItems();
    HTMLElement* element = listItems[listIndex];
    OptionElement* optionElement = toOptionElement(element);

    Color backColor;
    if (optionElement && optionElement->selected()) {
        if (document()->frame()->selection()->isFocusedAndActive() && document()->focusedNode() == node())
            backColor = theme()->activeListBoxSelectionBackgroundColor();
        else
            backColor = theme()->inactiveListBoxSelectionBackgroundColor();
    } else
        backColor = element->renderStyle() ? element->renderStyle()->backgroundColor() : style()->backgroundColor();

    // Draw the background for this list box item
    if (!element->renderStyle() || element->renderStyle()->visibility() != HIDDEN) {
        IntRect itemRect = itemBoundingBoxRect(tx, ty, listIndex);
        itemRect.intersect(controlClipRect(tx, ty));
        paintInfo.context->fillRect(itemRect, backColor);
    }
}

bool RenderListBox::isPointInOverflowControl(HitTestResult& result, int _x, int _y, int _tx, int _ty)
{
    if (!m_vBar)
        return false;

    IntRect vertRect(_tx + width() - borderRight() - m_vBar->width(),
                     _ty,
                     m_vBar->width(),
                     height() - borderTop() - borderBottom());

    if (vertRect.contains(_x, _y)) {
        result.setScrollbar(m_vBar.get());
        return true;
    }
    return false;
}

int RenderListBox::listIndexAtOffset(int offsetX, int offsetY)
{
    if (!numItems())
        return -1;

    if (offsetY < borderTop() + paddingTop() || offsetY > height() - paddingBottom() - borderBottom())
        return -1;

    int scrollbarWidth = m_vBar ? m_vBar->width() : 0;
    if (offsetX < borderLeft() + paddingLeft() || offsetX > width() - borderRight() - paddingRight() - scrollbarWidth)
        return -1;

    int newOffset = (offsetY - borderTop() - paddingTop()) / itemHeight() + m_indexOffset;
    return newOffset < numItems() ? newOffset : -1;
}

void RenderListBox::panScroll(const IntPoint& panStartMousePosition)
{
    const int maxSpeed = 20;
    const int iconRadius = 7;
    const int speedReducer = 4;

    // FIXME: This doesn't work correctly with transforms.
    FloatPoint absOffset = localToAbsolute();

    IntPoint currentMousePosition = document()->frame()->eventHandler()->currentMousePosition();
    // We need to check if the current mouse position is out of the window. When the mouse is out of the window, the position is incoherent
    static IntPoint previousMousePosition;
    if (currentMousePosition.y() < 0)
        currentMousePosition = previousMousePosition;
    else
        previousMousePosition = currentMousePosition;

    int yDelta = currentMousePosition.y() - panStartMousePosition.y();

   // If the point is too far from the center we limit the speed
    yDelta = max(min(yDelta, maxSpeed), -maxSpeed);
    
    if(abs(yDelta) < iconRadius) // at the center we let the space for the icon
        return;

    if (yDelta > 0)
        //offsetY = view()->viewHeight();
        absOffset.move(0, listHeight());
   else if (yDelta < 0)
       yDelta--;

    // Let's attenuate the speed
    yDelta /= speedReducer;

    IntPoint scrollPoint(0,0);
    scrollPoint.setY(absOffset.y() + yDelta);
    int newOffset = scrollToward(scrollPoint);
    if (newOffset < 0) 
        return;

    m_inAutoscroll = true;
    HTMLSelectElement* select = static_cast<HTMLSelectElement*>(node());
    select->updateListBoxSelection(!select->multiple());
    m_inAutoscroll = false;
}

int RenderListBox::scrollToward(const IntPoint& destination)
{
    // FIXME: This doesn't work correctly with transforms.
    FloatPoint absPos = localToAbsolute();
    int offsetX = destination.x() - absPos.x();
    int offsetY = destination.y() - absPos.y();

    int rows = numVisibleItems();
    int offset = m_indexOffset;
    
    if (offsetY < borderTop() + paddingTop() && scrollToRevealElementAtListIndex(offset - 1))
        return offset - 1;
    
    if (offsetY > height() - paddingBottom() - borderBottom() && scrollToRevealElementAtListIndex(offset + rows))
        return offset + rows - 1;
    
    return listIndexAtOffset(offsetX, offsetY);
}

void RenderListBox::autoscroll()
{
    IntPoint pos = document()->frame()->view()->windowToContents(document()->frame()->eventHandler()->currentMousePosition());

    int endIndex = scrollToward(pos);
    if (endIndex >= 0) {
        HTMLSelectElement* select = static_cast<HTMLSelectElement*>(node());
        m_inAutoscroll = true;

        if (!select->multiple())
            select->setActiveSelectionAnchorIndex(endIndex);

        select->setActiveSelectionEndIndex(endIndex);
        select->updateListBoxSelection(!select->multiple());
        m_inAutoscroll = false;
    }
}

void RenderListBox::stopAutoscroll()
{
    static_cast<HTMLSelectElement*>(node())->listBoxOnChange();
}

bool RenderListBox::scrollToRevealElementAtListIndex(int index)
{
    if (index < 0 || index >= numItems() || listIndexIsVisible(index))
        return false;

    int newOffset;
    if (index < m_indexOffset)
        newOffset = index;
    else
        newOffset = index - numVisibleItems() + 1;

    m_indexOffset = newOffset;
    if (m_vBar)
        m_vBar->setValue(m_indexOffset);

    return true;
}

bool RenderListBox::listIndexIsVisible(int index)
{    
    return index >= m_indexOffset && index < m_indexOffset + numVisibleItems();
}

bool RenderListBox::scroll(ScrollDirection direction, ScrollGranularity granularity, float multiplier)
{
    return m_vBar && m_vBar->scroll(direction, granularity, multiplier);
}

void RenderListBox::valueChanged(unsigned listIndex)
{
    HTMLSelectElement* select = static_cast<HTMLSelectElement*>(node());
    select->setSelectedIndex(select->listToOptionIndex(listIndex));
    select->onChange();
}

void RenderListBox::valueChanged(Scrollbar*)
{
    int newOffset = m_vBar->value();
    if (newOffset != m_indexOffset) {
        m_indexOffset = newOffset;
        repaint();
        // Fire the scroll DOM event.
        node()->dispatchEventForType(eventNames().scrollEvent, false, false);
    }
}

int RenderListBox::itemHeight() const
{
    return style()->font().height() + rowSpacing;
}

int RenderListBox::verticalScrollbarWidth() const
{
    return m_vBar ? m_vBar->width() : 0;
}

// FIXME: We ignore padding in the vertical direction as far as these values are concerned, since that's
// how the control currently paints.
int RenderListBox::scrollWidth() const
{
    // There is no horizontal scrolling allowed.
    return clientWidth();
}

int RenderListBox::scrollHeight() const
{
    return max(clientHeight(), listHeight());
}

int RenderListBox::scrollLeft() const
{
    return 0;
}

void RenderListBox::setScrollLeft(int)
{
}

int RenderListBox::scrollTop() const
{
    return m_indexOffset * itemHeight();
}

void RenderListBox::setScrollTop(int newTop)
{
    // Determine an index and scroll to it.    
    int index = newTop / itemHeight();
    if (index < 0 || index >= numItems() || index == m_indexOffset)
        return;
    m_indexOffset = index;
    if (m_vBar)
        m_vBar->setValue(index);
}

bool RenderListBox::nodeAtPoint(const HitTestRequest& request, HitTestResult& result, int x, int y, int tx, int ty, HitTestAction hitTestAction)
{
    if (!RenderBlock::nodeAtPoint(request, result, x, y, tx, ty, hitTestAction))
        return false;
    const Vector<HTMLElement*>& listItems = static_cast<HTMLSelectElement*>(node())->listItems();
    int size = numItems();
    tx += this->x();
    ty += this->y();
    for (int i = 0; i < size; ++i) {
        if (itemBoundingBoxRect(tx, ty, i).contains(x, y)) {
            if (HTMLElement* node = listItems[i]) {
                result.setInnerNode(node);
                if (!result.innerNonSharedNode())
                    result.setInnerNonSharedNode(node);
                result.setLocalPoint(IntPoint(x - tx, y - ty));
                break;
            }
        }
    }

    return true;
}

IntRect RenderListBox::controlClipRect(int tx, int ty) const
{
    IntRect clipRect = contentBoxRect();
    clipRect.move(tx, ty);
    return clipRect;
}

bool RenderListBox::isActive() const
{
    Page* page = document()->frame()->page();
    return page && page->focusController()->isActive();
}

void RenderListBox::invalidateScrollbarRect(Scrollbar* scrollbar, const IntRect& rect)
{
    IntRect scrollRect = rect;
    scrollRect.move(width() - borderRight() - scrollbar->width(), borderTop());
    repaintRectangle(scrollRect);
}

PassRefPtr<Scrollbar> RenderListBox::createScrollbar()
{
    RefPtr<Scrollbar> widget;
    bool hasCustomScrollbarStyle = style()->hasPseudoStyle(SCROLLBAR);
    if (hasCustomScrollbarStyle)
        widget = RenderScrollbar::createCustomScrollbar(this, VerticalScrollbar, this);
    else
        widget = Scrollbar::createNativeScrollbar(this, VerticalScrollbar, theme()->scrollbarControlSizeForPart(ListboxPart));
    document()->view()->addChild(widget.get());        
    return widget.release();
}

void RenderListBox::destroyScrollbar()
{
    if (!m_vBar)
        return;
    
    m_vBar->removeFromParent();
    m_vBar->setClient(0);
    m_vBar = 0;
}

void RenderListBox::setHasVerticalScrollbar(bool hasScrollbar)
{
    if (hasScrollbar == (m_vBar != 0))
        return;

    if (hasScrollbar)
        m_vBar = createScrollbar();
    else
        destroyScrollbar();

    if (m_vBar)
        m_vBar->styleChanged();

#if ENABLE(DASHBOARD_SUPPORT)
    // Force an update since we know the scrollbars have changed things.
    if (document()->hasDashboardRegions())
        document()->setDashboardRegionsDirty(true);
#endif
}

} // namespace WebCore