gecko-dev/layout/svg/SVGViewFrame.cpp

107 строки
3.7 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
// Keep in (case-insensitive) order:
#include "mozilla/PresShell.h"
#include "mozilla/dom/SVGSVGElement.h"
#include "mozilla/dom/SVGViewElement.h"
#include "nsFrame.h"
#include "nsGkAtoms.h"
#include "nsSVGOuterSVGFrame.h"
using namespace mozilla;
using namespace mozilla::dom;
/**
* While views are not directly rendered in SVG they can be linked to
* and thereby override attributes of an <svg> element via a fragment
* identifier. The SVGViewFrame class passes on any attribute changes
* the view receives to the overridden <svg> element (if there is one).
**/
class SVGViewFrame final : public nsFrame {
friend nsIFrame* NS_NewSVGViewFrame(mozilla::PresShell* aPresShell,
ComputedStyle* aStyle);
protected:
explicit SVGViewFrame(ComputedStyle* aStyle, nsPresContext* aPresContext)
: nsFrame(aStyle, aPresContext, kClassID) {
AddStateBits(NS_FRAME_SVG_LAYOUT | NS_FRAME_IS_NONDISPLAY);
}
public:
NS_DECL_FRAMEARENA_HELPERS(SVGViewFrame)
#ifdef DEBUG
virtual void Init(nsIContent* aContent, nsContainerFrame* aParent,
nsIFrame* aPrevInFlow) override;
#endif
virtual bool IsFrameOfType(uint32_t aFlags) const override {
if (aFlags & eSupportsContainLayoutAndPaint) {
return false;
}
return nsFrame::IsFrameOfType(aFlags & ~(nsIFrame::eSVG));
}
#ifdef DEBUG_FRAME_DUMP
virtual nsresult GetFrameName(nsAString& aResult) const override {
return MakeFrameName(NS_LITERAL_STRING("SVGView"), aResult);
}
#endif
virtual nsresult AttributeChanged(int32_t aNameSpaceID, nsAtom* aAttribute,
int32_t aModType) override;
virtual bool ComputeCustomOverflow(nsOverflowAreas& aOverflowAreas) override {
// We don't maintain a visual overflow rect
return false;
}
};
nsIFrame* NS_NewSVGViewFrame(PresShell* aPresShell, ComputedStyle* aStyle) {
return new (aPresShell) SVGViewFrame(aStyle, aPresShell->GetPresContext());
}
NS_IMPL_FRAMEARENA_HELPERS(SVGViewFrame)
#ifdef DEBUG
void SVGViewFrame::Init(nsIContent* aContent, nsContainerFrame* aParent,
nsIFrame* aPrevInFlow) {
NS_ASSERTION(aContent->IsSVGElement(nsGkAtoms::view),
"Content is not an SVG view");
nsFrame::Init(aContent, aParent, aPrevInFlow);
}
#endif /* DEBUG */
nsresult SVGViewFrame::AttributeChanged(int32_t aNameSpaceID,
nsAtom* aAttribute, int32_t aModType) {
// Ignore zoomAndPan as it does not cause the <svg> element to re-render
if (aNameSpaceID == kNameSpaceID_None &&
(aAttribute == nsGkAtoms::preserveAspectRatio ||
aAttribute == nsGkAtoms::viewBox)) {
nsSVGOuterSVGFrame* outerSVGFrame = nsSVGUtils::GetOuterSVGFrame(this);
NS_ASSERTION(outerSVGFrame->GetContent()->IsSVGElement(nsGkAtoms::svg),
"Expecting an <svg> element");
SVGSVGElement* svgElement =
static_cast<SVGSVGElement*>(outerSVGFrame->GetContent());
nsAutoString viewID;
mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::id, viewID);
if (svgElement->IsOverriddenBy(viewID)) {
// We're the view that's providing overrides, so pretend that the frame
// we're overriding was updated.
outerSVGFrame->AttributeChanged(aNameSpaceID, aAttribute, aModType);
}
}
return nsFrame::AttributeChanged(aNameSpaceID, aAttribute, aModType);
}