C++ RenderStyle::backgroundImage方法代码示例

static bool isDeletableElement(const Node* node)
{
    if (!node || !node->isHTMLElement() || !node->inDocument() || !node->isContentEditable())
        return false;

    // In general we want to only draw the UI arround object of a certain area, but we still keep the min width/height to
    // make sure we don't end up with very thin or very short elements getting the UI.
    const int minimumArea = 2500;
    const int minimumWidth = 48;
    const int minimumHeight = 16;
    const unsigned minimumVisibleBorders = 1;

    RenderObject* renderer = node->renderer();
    if (!renderer || !renderer->isBox())
        return false;

    // Disallow the body element since it isn't practical to delete, and the deletion UI would be clipped.
    if (node->hasTagName(bodyTag))
        return false;

    // Disallow elements with any overflow clip, since the deletion UI would be clipped as well. <rdar://problem/6840161>
    if (renderer->hasOverflowClip())
        return false;

    // Disallow Mail blockquotes since the deletion UI would get in the way of editing for these.
    if (isMailBlockquote(node))
        return false;

    RenderBox* box = toRenderBox(renderer);
    IntRect borderBoundingBox = box->borderBoundingBox();
    if (borderBoundingBox.width() < minimumWidth || borderBoundingBox.height() < minimumHeight)
        return false;

    if ((borderBoundingBox.width() * borderBoundingBox.height()) < minimumArea)
        return false;

    if (renderer->isTable())
        return true;

    if (node->hasTagName(ulTag) || node->hasTagName(olTag) || node->hasTagName(iframeTag))
        return true;

    if (renderer->isPositioned())
        return true;

    if (renderer->isRenderBlock() && !renderer->isTableCell()) {
        RenderStyle* style = renderer->style();
        if (!style)
            return false;

        // Allow blocks that have background images
        if (style->hasBackgroundImage() && style->backgroundImage()->canRender(1.0f))
            return true;

        // Allow blocks with a minimum number of non-transparent borders
        unsigned visibleBorders = style->borderTop().isVisible() + style->borderBottom().isVisible() + style->borderLeft().isVisible() + style->borderRight().isVisible();
        if (visibleBorders >= minimumVisibleBorders)
            return true;

        // Allow blocks that have a different background from it's parent
        Node* parentNode = node->parentNode();
        if (!parentNode)
            return false;

        RenderObject* parentRenderer = parentNode->renderer();
        if (!parentRenderer)
            return false;

        RenderStyle* parentStyle = parentRenderer->style();
        if (!parentStyle)
            return false;

        if (style->hasBackground() && (!parentStyle->hasBackground() || style->backgroundColor() != parentStyle->backgroundColor()))
            return true;
    }

    return false;
}

CSSValueImpl *CSSComputedStyleDeclarationImpl::getPropertyCSSValue(int propertyID, EUpdateLayout updateLayout) const
{
    NodeImpl *node = m_node.handle();
    if (!node)
        return 0;

    // Make sure our layout is up to date before we allow a query on these attributes.
    DocumentImpl* docimpl = node->getDocument();
    if (docimpl && updateLayout)
        docimpl->updateLayout();

    RenderObject *renderer = node->renderer();
    if (!renderer)
        return 0;
    RenderStyle *style = renderer->style();
    if (!style)
        return 0;

    switch (propertyID)
    {
    case CSS_PROP_BACKGROUND_COLOR:
        return new CSSPrimitiveValueImpl(style->backgroundColor().rgb());
    case CSS_PROP_BACKGROUND_IMAGE:
        if (style->backgroundImage())
            return new CSSPrimitiveValueImpl(style->backgroundImage()->url(), CSSPrimitiveValue::CSS_URI);
        return new CSSPrimitiveValueImpl(CSS_VAL_NONE);
    case CSS_PROP_BACKGROUND_REPEAT:
        switch (style->backgroundRepeat()) {
            case khtml::REPEAT:
                return new CSSPrimitiveValueImpl(CSS_VAL_REPEAT);
            case khtml::REPEAT_X:
                return new CSSPrimitiveValueImpl(CSS_VAL_REPEAT_X);
            case khtml::REPEAT_Y:
                return new CSSPrimitiveValueImpl(CSS_VAL_REPEAT_Y);
            case khtml::NO_REPEAT:
                return new CSSPrimitiveValueImpl(CSS_VAL_NO_REPEAT);
        }
        ASSERT_NOT_REACHED();
        return 0;
    case CSS_PROP_BACKGROUND_ATTACHMENT:
        if (style->backgroundAttachment())
            return new CSSPrimitiveValueImpl(CSS_VAL_SCROLL);
        else
            return new CSSPrimitiveValueImpl(CSS_VAL_FIXED);
    case CSS_PROP_BACKGROUND_POSITION:
    {
        DOMString string;
        Length length(style->backgroundXPosition());
        if (length.isPercent())
            string = numberAsString(length.length()) + "%";
        else
            string = numberAsString(length.minWidth(renderer->contentWidth()));
        string += " ";
        length = style->backgroundYPosition();
        if (length.isPercent())
            string += numberAsString(length.length()) + "%";
        else
            string += numberAsString(length.minWidth(renderer->contentWidth()));
        return new CSSPrimitiveValueImpl(string, CSSPrimitiveValue::CSS_STRING);
    }
    case CSS_PROP_BACKGROUND_POSITION_X:
        return valueForLength(style->backgroundXPosition());
    case CSS_PROP_BACKGROUND_POSITION_Y:
        return valueForLength(style->backgroundYPosition());
#ifndef KHTML_NO_XBL
    case CSS_PROP__KHTML_BINDING:
        // FIXME: unimplemented
        break;
#endif
    case CSS_PROP_BORDER_COLLAPSE:
        if (style->borderCollapse())
            return new CSSPrimitiveValueImpl(CSS_VAL_COLLAPSE);
        else
            return new CSSPrimitiveValueImpl(CSS_VAL_SEPARATE);
    case CSS_PROP_BORDER_SPACING:
    {
        QString string(numberAsString(style->horizontalBorderSpacing()) + 
            "px " + 
            numberAsString(style->verticalBorderSpacing()) +
            "px");
        return new CSSPrimitiveValueImpl(string, CSSPrimitiveValue::CSS_STRING);
    }
    case CSS_PROP__KHTML_BORDER_HORIZONTAL_SPACING:
        return new CSSPrimitiveValueImpl(style->horizontalBorderSpacing(), CSSPrimitiveValue::CSS_PX);
    case CSS_PROP__KHTML_BORDER_VERTICAL_SPACING:
        return new CSSPrimitiveValueImpl(style->verticalBorderSpacing(), CSSPrimitiveValue::CSS_PX);
    case CSS_PROP_BORDER_TOP_COLOR:
        return new CSSPrimitiveValueImpl(style->borderLeftColor().rgb());
    case CSS_PROP_BORDER_RIGHT_COLOR:
        return new CSSPrimitiveValueImpl(style->borderRightColor().rgb());
    case CSS_PROP_BORDER_BOTTOM_COLOR:
        return new CSSPrimitiveValueImpl(style->borderBottomColor().rgb());
    case CSS_PROP_BORDER_LEFT_COLOR:
        return new CSSPrimitiveValueImpl(style->borderLeftColor().rgb());
    case CSS_PROP_BORDER_TOP_STYLE:
        return valueForBorderStyle(style->borderTopStyle());
    case CSS_PROP_BORDER_RIGHT_STYLE:
        return valueForBorderStyle(style->borderRightStyle());
    case CSS_PROP_BORDER_BOTTOM_STYLE:
        return valueForBorderStyle(style->borderBottomStyle());
//.........这里部分代码省略.........