gecko-dev/accessible/generic/ImageAccessible.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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/. */
#include "ImageAccessible.h"
#include "nsAccUtils.h"
#include "Role.h"
#include "AccIterator.h"
#include "States.h"
#include "imgIContainer.h"
#include "imgIRequest.h"
#include "nsGenericHTMLElement.h"
#include "mozilla/dom/BrowsingContext.h"
#include "mozilla/dom/Document.h"
#include "nsIImageLoadingContent.h"
#include "nsIServiceManager.h"
#include "nsIPersistentProperties2.h"
#include "nsPIDOMWindow.h"
#include "nsIURI.h"
using namespace mozilla::a11y;
////////////////////////////////////////////////////////////////////////////////
// ImageAccessible
////////////////////////////////////////////////////////////////////////////////
ImageAccessible::ImageAccessible(nsIContent* aContent, DocAccessible* aDoc)
: LinkableAccessible(aContent, aDoc) {
mType = eImageType;
}
ImageAccessible::~ImageAccessible() {}
////////////////////////////////////////////////////////////////////////////////
// Accessible public
uint64_t ImageAccessible::NativeState() const {
// The state is a bitfield, get our inherited state, then logically OR it with
// states::ANIMATED if this is an animated image.
uint64_t state = LinkableAccessible::NativeState();
nsCOMPtr<nsIImageLoadingContent> content(do_QueryInterface(mContent));
nsCOMPtr<imgIRequest> imageRequest;
if (content)
content->GetRequest(nsIImageLoadingContent::CURRENT_REQUEST,
getter_AddRefs(imageRequest));
nsCOMPtr<imgIContainer> imgContainer;
if (imageRequest) imageRequest->GetImage(getter_AddRefs(imgContainer));
if (imgContainer) {
bool animated = false;
imgContainer->GetAnimated(&animated);
if (animated) state |= states::ANIMATED;
}
return state;
}
ENameValueFlag ImageAccessible::NativeName(nsString& aName) const {
bool hasAltAttrib =
mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::alt, aName);
if (!aName.IsEmpty()) return eNameOK;
ENameValueFlag nameFlag = Accessible::NativeName(aName);
if (!aName.IsEmpty()) return nameFlag;
// No accessible name but empty 'alt' attribute is present. If further name
// computation algorithm doesn't provide non empty name then it means
// an empty 'alt' attribute was used to indicate a decorative image (see
// Accessible::Name() method for details).
return hasAltAttrib ? eNoNameOnPurpose : eNameOK;
}
role ImageAccessible::NativeRole() const { return roles::GRAPHIC; }
////////////////////////////////////////////////////////////////////////////////
// Accessible
uint8_t ImageAccessible::ActionCount() const {
uint8_t actionCount = LinkableAccessible::ActionCount();
return HasLongDesc() ? actionCount + 1 : actionCount;
}
void ImageAccessible::ActionNameAt(uint8_t aIndex, nsAString& aName) {
aName.Truncate();
if (IsLongDescIndex(aIndex) && HasLongDesc())
aName.AssignLiteral("showlongdesc");
else
LinkableAccessible::ActionNameAt(aIndex, aName);
}
bool ImageAccessible::DoAction(uint8_t aIndex) const {
// Get the long description uri and open in a new window.
if (!IsLongDescIndex(aIndex)) return LinkableAccessible::DoAction(aIndex);
nsCOMPtr<nsIURI> uri = GetLongDescURI();
if (!uri) return false;
nsAutoCString utf8spec;
uri->GetSpec(utf8spec);
NS_ConvertUTF8toUTF16 spec(utf8spec);
dom::Document* document = mContent->OwnerDoc();
nsCOMPtr<nsPIDOMWindowOuter> piWindow = document->GetWindow();
if (!piWindow) return false;
RefPtr<mozilla::dom::BrowsingContext> tmp;
return NS_SUCCEEDED(piWindow->Open(spec, EmptyString(), EmptyString(),
/* aLoadInfo = */ nullptr,
/* aForceNoOpener = */ false,
getter_AddRefs(tmp)));
}
////////////////////////////////////////////////////////////////////////////////
// ImageAccessible
nsIntPoint ImageAccessible::Position(uint32_t aCoordType) {
nsIntPoint point = Bounds().TopLeft();
nsAccUtils::ConvertScreenCoordsTo(&point.x, &point.y, aCoordType, this);
return point;
}
nsIntSize ImageAccessible::Size() { return Bounds().Size(); }
// Accessible
already_AddRefed<nsIPersistentProperties> ImageAccessible::NativeAttributes() {
nsCOMPtr<nsIPersistentProperties> attributes =
LinkableAccessible::NativeAttributes();
nsAutoString src;
mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::src, src);
if (!src.IsEmpty()) nsAccUtils::SetAccAttr(attributes, nsGkAtoms::src, src);
return attributes.forget();
}
////////////////////////////////////////////////////////////////////////////////
// Private methods
already_AddRefed<nsIURI> ImageAccessible::GetLongDescURI() const {
if (mContent->AsElement()->HasAttr(kNameSpaceID_None, nsGkAtoms::longdesc)) {
// To check if longdesc contains an invalid url.
nsAutoString longdesc;
mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::longdesc,
longdesc);
if (longdesc.FindChar(' ') != -1 || longdesc.FindChar('\t') != -1 ||
longdesc.FindChar('\r') != -1 || longdesc.FindChar('\n') != -1) {
return nullptr;
}
nsCOMPtr<nsIURI> uri;
nsContentUtils::NewURIWithDocumentCharset(getter_AddRefs(uri), longdesc,
mContent->OwnerDoc(),
mContent->GetBaseURI());
return uri.forget();
}
DocAccessible* document = Document();
if (document) {
IDRefsIterator iter(document, mContent, nsGkAtoms::aria_describedby);
while (nsIContent* target = iter.NextElem()) {
if ((target->IsHTMLElement(nsGkAtoms::a) ||
target->IsHTMLElement(nsGkAtoms::area)) &&
target->AsElement()->HasAttr(kNameSpaceID_None, nsGkAtoms::href)) {
nsGenericHTMLElement* element = nsGenericHTMLElement::FromNode(target);
nsCOMPtr<nsIURI> uri;
element->GetURIAttr(nsGkAtoms::href, nullptr, getter_AddRefs(uri));
return uri.forget();
}
}
}
return nullptr;
}
bool ImageAccessible::IsLongDescIndex(uint8_t aIndex) const {
return aIndex == LinkableAccessible::ActionCount();
}