PassRefPtr<ComputedStyle> LayoutScrollbar::getScrollbarPseudoStyle(ScrollbarPart partType, PseudoId pseudoId)
{
if (!owningLayoutObject())
return nullptr;
RefPtr<ComputedStyle> result = owningLayoutObject()->getUncachedPseudoStyle(PseudoStyleRequest(pseudoId, this, partType), owningLayoutObject()->style());
// Scrollbars for root frames should always have background color
// unless explicitly specified as transparent. So we force it.
// This is because WebKit assumes scrollbar to be always painted and missing background
// causes visual artifact like non-paint invalidated dirty region.
if (result && m_owningFrame && m_owningFrame->view() && !m_owningFrame->view()->isTransparent() && !result->hasBackground())
result->setBackgroundColor(StyleColor(Color::white));
return result;
}
void LayoutScrollbar::updateScrollbarPart(ScrollbarPart partType, bool destroy)
{
if (partType == NoPart)
return;
RefPtr<ComputedStyle> partStyle = !destroy ? getScrollbarPseudoStyle(partType, pseudoForScrollbarPart(partType)) : PassRefPtr<ComputedStyle>(nullptr);
bool needLayoutObject = !destroy && partStyle && partStyle->display() != NONE;
if (needLayoutObject && partStyle->display() != BLOCK) {
// See if we are a button that should not be visible according to OS settings.
ScrollbarButtonsPlacement buttonsPlacement = theme()->buttonsPlacement();
switch (partType) {
case BackButtonStartPart:
needLayoutObject = (buttonsPlacement == ScrollbarButtonsPlacementSingle || buttonsPlacement == ScrollbarButtonsPlacementDoubleStart
|| buttonsPlacement == ScrollbarButtonsPlacementDoubleBoth);
break;
case ForwardButtonStartPart:
needLayoutObject = (buttonsPlacement == ScrollbarButtonsPlacementDoubleStart || buttonsPlacement == ScrollbarButtonsPlacementDoubleBoth);
break;
case BackButtonEndPart:
needLayoutObject = (buttonsPlacement == ScrollbarButtonsPlacementDoubleEnd || buttonsPlacement == ScrollbarButtonsPlacementDoubleBoth);
break;
case ForwardButtonEndPart:
needLayoutObject = (buttonsPlacement == ScrollbarButtonsPlacementSingle || buttonsPlacement == ScrollbarButtonsPlacementDoubleEnd
|| buttonsPlacement == ScrollbarButtonsPlacementDoubleBoth);
break;
default:
break;
}
}
LayoutScrollbarPart* partLayoutObject = m_parts.get(partType);
if (!partLayoutObject && needLayoutObject) {
partLayoutObject = LayoutScrollbarPart::createAnonymous(&owningLayoutObject()->document(), this, partType);
m_parts.set(partType, partLayoutObject);
} else if (partLayoutObject && !needLayoutObject) {
m_parts.remove(partType);
partLayoutObject->destroy();
partLayoutObject = 0;
}
if (partLayoutObject)
partLayoutObject->setStyle(partStyle.release());
}
void LayoutScrollbar::updateScrollbarParts(bool destroy)
{
updateScrollbarPart(ScrollbarBGPart, destroy);
updateScrollbarPart(BackButtonStartPart, destroy);
updateScrollbarPart(ForwardButtonStartPart, destroy);
updateScrollbarPart(BackTrackPart, destroy);
updateScrollbarPart(ThumbPart, destroy);
updateScrollbarPart(ForwardTrackPart, destroy);
updateScrollbarPart(BackButtonEndPart, destroy);
updateScrollbarPart(ForwardButtonEndPart, destroy);
updateScrollbarPart(TrackBGPart, destroy);
if (destroy)
return;
// See if the scrollbar's thickness changed. If so, we need to mark our owning object as needing a layout.
bool isHorizontal = orientation() == HorizontalScrollbar;
int oldThickness = isHorizontal ? height() : width();
int newThickness = 0;
LayoutScrollbarPart* part = m_parts.get(ScrollbarBGPart);
if (part) {
part->layout();
newThickness = isHorizontal ? part->size().height() : part->size().width();
}
if (newThickness != oldThickness) {
setFrameRect(IntRect(location(), IntSize(isHorizontal ? width() : newThickness, isHorizontal ? newThickness : height())));
if (LayoutBox* box = owningLayoutObject()) {
if (box->isLayoutBlock())
toLayoutBlock(box)->notifyScrollbarThicknessChanged();
box->setChildNeedsLayout();
if (RuntimeEnabledFeatures::slimmingPaintEnabled() && m_scrollableArea)
m_scrollableArea->invalidateScrollCorner(m_scrollableArea->scrollCornerRect());
}
}
}
void LayoutScrollbar::updateScrollbarPart(ScrollbarPart partType,
bool destroy) {
if (partType == NoPart)
return;
RefPtr<ComputedStyle> partStyle =
!destroy
? getScrollbarPseudoStyle(partType, pseudoForScrollbarPart(partType))
: PassRefPtr<ComputedStyle>(nullptr);
bool needLayoutObject =
!destroy && partStyle && partStyle->display() != EDisplay::None;
if (needLayoutObject && partStyle->display() != EDisplay::Block) {
// See if we are a button that should not be visible according to OS
// settings.
WebScrollbarButtonsPlacement buttonsPlacement = theme().buttonsPlacement();
switch (partType) {
case BackButtonStartPart:
needLayoutObject =
(buttonsPlacement == WebScrollbarButtonsPlacementSingle ||
buttonsPlacement == WebScrollbarButtonsPlacementDoubleStart ||
buttonsPlacement == WebScrollbarButtonsPlacementDoubleBoth);
break;
case ForwardButtonStartPart:
needLayoutObject =
(buttonsPlacement == WebScrollbarButtonsPlacementDoubleStart ||
buttonsPlacement == WebScrollbarButtonsPlacementDoubleBoth);
break;
case BackButtonEndPart:
needLayoutObject =
(buttonsPlacement == WebScrollbarButtonsPlacementDoubleEnd ||
buttonsPlacement == WebScrollbarButtonsPlacementDoubleBoth);
break;
case ForwardButtonEndPart:
needLayoutObject =
(buttonsPlacement == WebScrollbarButtonsPlacementSingle ||
buttonsPlacement == WebScrollbarButtonsPlacementDoubleEnd ||
buttonsPlacement == WebScrollbarButtonsPlacementDoubleBoth);
break;
default:
break;
}
}
LayoutScrollbarPart* partLayoutObject = m_parts.get(partType);
if (!partLayoutObject && needLayoutObject && m_scrollableArea) {
partLayoutObject = LayoutScrollbarPart::createAnonymous(
&owningLayoutObject()->document(), m_scrollableArea, this, partType);
m_parts.set(partType, partLayoutObject);
setNeedsPaintInvalidation(partType);
} else if (partLayoutObject && !needLayoutObject) {
m_parts.remove(partType);
partLayoutObject->destroy();
partLayoutObject = nullptr;
if (!destroy)
setNeedsPaintInvalidation(partType);
}
if (partLayoutObject)
partLayoutObject->setStyleWithWritingModeOfParent(partStyle.release());
}
LayoutBox* LayoutScrollbar::owningLayoutObjectWithinFrame() const {
if (m_owningFrame)
return m_owningFrame->contentLayoutObject();
return owningLayoutObject();
}
