gecko-dev/dom/html/HTMLImageElement.h

374 lines
14 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/. */
#ifndef mozilla_dom_HTMLImageElement_h
#define mozilla_dom_HTMLImageElement_h
#include "mozilla/Attributes.h"
#include "nsGenericHTMLElement.h"
#include "nsImageLoadingContent.h"
#include "nsIDOMHTMLImageElement.h"
#include "imgRequestProxy.h"
#include "Units.h"
#include "nsCycleCollectionParticipant.h"
// Only needed for IsPictureEnabled()
#include "mozilla/dom/HTMLPictureElement.h"
namespace mozilla {
class EventChainPreVisitor;
namespace dom {
class ImageLoadTask;
class ResponsiveImageSelector;
class HTMLImageElement final : public nsGenericHTMLElement,
public nsImageLoadingContent,
public nsIDOMHTMLImageElement
{
friend class HTMLSourceElement;
friend class HTMLPictureElement;
friend class ImageLoadTask;
public:
explicit HTMLImageElement(already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo);
static already_AddRefed<HTMLImageElement>
Image(const GlobalObject& aGlobal,
const Optional<uint32_t>& aWidth,
const Optional<uint32_t>& aHeight,
ErrorResult& aError);
NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(HTMLImageElement,
nsGenericHTMLElement)
// nsISupports
NS_DECL_ISUPPORTS_INHERITED
virtual bool Draggable() const override;
// Element
virtual bool IsInteractiveHTMLContent(bool aIgnoreTabindex) const override;
// nsIDOMHTMLImageElement
NS_DECL_NSIDOMHTMLIMAGEELEMENT
NS_IMPL_FROMCONTENT_HTML_WITH_TAG(HTMLImageElement, img)
// override from nsImageLoadingContent
CORSMode GetCORSMode() override;
// nsIContent
virtual bool ParseAttribute(int32_t aNamespaceID,
nsIAtom* aAttribute,
const nsAString& aValue,
nsAttrValue& aResult) override;
virtual nsChangeHint GetAttributeChangeHint(const nsIAtom* aAttribute,
int32_t aModType) const override;
NS_IMETHOD_(bool) IsAttributeMapped(const nsIAtom* aAttribute) const override;
virtual nsMapRuleToAttributesFunc GetAttributeMappingFunction() const override;
virtual nsresult PreHandleEvent(EventChainPreVisitor& aVisitor) override;
bool IsHTMLFocusable(bool aWithMouse, bool *aIsFocusable, int32_t *aTabIndex) override;
// SetAttr override. C++ is stupid, so have to override both
// overloaded methods.
nsresult SetAttr(int32_t aNameSpaceID, nsIAtom* aName,
const nsAString& aValue, bool aNotify)
{
return SetAttr(aNameSpaceID, aName, nullptr, aValue, aNotify);
}
virtual nsresult SetAttr(int32_t aNameSpaceID, nsIAtom* aName,
nsIAtom* aPrefix, const nsAString& aValue,
bool aNotify) override;
virtual nsresult BindToTree(nsIDocument* aDocument, nsIContent* aParent,
nsIContent* aBindingParent,
bool aCompileEventHandlers) override;
virtual void UnbindFromTree(bool aDeep, bool aNullParent) override;
virtual EventStates IntrinsicState() const override;
virtual nsresult Clone(mozilla::dom::NodeInfo *aNodeInfo, nsINode **aResult) const override;
nsresult CopyInnerTo(Element* aDest);
void MaybeLoadImage();
static bool IsSrcsetEnabled();
bool IsMap()
{
return GetBoolAttr(nsGkAtoms::ismap);
}
void SetIsMap(bool aIsMap, ErrorResult& aError)
{
SetHTMLBoolAttr(nsGkAtoms::ismap, aIsMap, aError);
}
uint32_t Width()
{
return GetWidthHeightForImage(mCurrentRequest).width;
}
void SetWidth(uint32_t aWidth, ErrorResult& aError)
{
SetUnsignedIntAttr(nsGkAtoms::width, aWidth, aError);
}
uint32_t Height()
{
return GetWidthHeightForImage(mCurrentRequest).height;
}
void SetHeight(uint32_t aHeight, ErrorResult& aError)
{
SetUnsignedIntAttr(nsGkAtoms::height, aHeight, aError);
}
uint32_t NaturalWidth();
uint32_t NaturalHeight();
bool Complete();
uint32_t Hspace()
{
return GetUnsignedIntAttr(nsGkAtoms::hspace, 0);
}
void SetHspace(uint32_t aHspace, ErrorResult& aError)
{
SetUnsignedIntAttr(nsGkAtoms::hspace, aHspace, aError);
}
uint32_t Vspace()
{
return GetUnsignedIntAttr(nsGkAtoms::vspace, 0);
}
void SetVspace(uint32_t aVspace, ErrorResult& aError)
{
SetUnsignedIntAttr(nsGkAtoms::vspace, aVspace, aError);
}
// The XPCOM versions of the following getters work for Web IDL bindings as well
void SetAlt(const nsAString& aAlt, ErrorResult& aError)
{
SetHTMLAttr(nsGkAtoms::alt, aAlt, aError);
}
void SetSrc(const nsAString& aSrc, ErrorResult& aError)
{
SetHTMLAttr(nsGkAtoms::src, aSrc, aError);
}
void SetSrcset(const nsAString& aSrcset, ErrorResult& aError)
{
SetHTMLAttr(nsGkAtoms::srcset, aSrcset, aError);
}
void GetCrossOrigin(nsAString& aResult)
{
// Null for both missing and invalid defaults is ok, since we
// always parse to an enum value, so we don't need an invalid
// default, and we _want_ the missing default to be null.
GetEnumAttr(nsGkAtoms::crossorigin, nullptr, aResult);
}
void SetCrossOrigin(const nsAString& aCrossOrigin, ErrorResult& aError)
{
SetOrRemoveNullableStringAttr(nsGkAtoms::crossorigin, aCrossOrigin, aError);
}
void SetUseMap(const nsAString& aUseMap, ErrorResult& aError)
{
SetHTMLAttr(nsGkAtoms::usemap, aUseMap, aError);
}
void SetName(const nsAString& aName, ErrorResult& aError)
{
SetHTMLAttr(nsGkAtoms::name, aName, aError);
}
void SetAlign(const nsAString& aAlign, ErrorResult& aError)
{
SetHTMLAttr(nsGkAtoms::align, aAlign, aError);
}
void SetLongDesc(const nsAString& aLongDesc, ErrorResult& aError)
{
SetHTMLAttr(nsGkAtoms::longdesc, aLongDesc, aError);
}
void SetSizes(const nsAString& aSizes, ErrorResult& aError)
{
SetHTMLAttr(nsGkAtoms::sizes, aSizes, aError);
}
void SetBorder(const nsAString& aBorder, ErrorResult& aError)
{
SetHTMLAttr(nsGkAtoms::border, aBorder, aError);
}
void SetReferrerPolicy(const nsAString& aReferrer, ErrorResult& aError)
{
SetHTMLAttr(nsGkAtoms::referrerpolicy, aReferrer, aError);
}
void GetReferrerPolicy(nsAString& aReferrer)
{
GetHTMLAttr(nsGkAtoms::referrerpolicy, aReferrer);
}
net::ReferrerPolicy
GetImageReferrerPolicy() override
{
return GetReferrerPolicyAsEnum();
}
int32_t X();
int32_t Y();
// Uses XPCOM GetLowsrc.
void SetLowsrc(const nsAString& aLowsrc, ErrorResult& aError)
{
SetHTMLAttr(nsGkAtoms::lowsrc, aLowsrc, aError);
}
#ifdef DEBUG
nsIDOMHTMLFormElement* GetForm() const;
#endif
void SetForm(nsIDOMHTMLFormElement* aForm);
void ClearForm(bool aRemoveFromForm);
virtual void DestroyContent() override;
void MediaFeatureValuesChanged();
/**
* Given a hypothetical <img> or <source> tag with the given parameters,
* return what URI we would attempt to use, if any. Used by the preloader to
* resolve sources prior to DOM creation.
*
* @param aDocument The document this image would be for, for referencing
* viewport width and DPI/zoom
* @param aIsSourceTag If these parameters are for a <source> tag (as in a
* <picture>) rather than an <img> tag. Note that some attrs are unused
* when this is true an vice versa
* @param aSrcAttr [ignored if aIsSourceTag] The src attr for this image.
* @param aSrcsetAttr The srcset attr for this image/source
* @param aSizesAttr The sizes attr for this image/source
* @param aTypeAttr [ignored if !aIsSourceTag] The type attr for this source.
* Should be a void string to differentiate no type attribute
* from an empty one.
* @param aMediaAttr [ignored if !aIsSourceTag] The media attr for this
* source. Should be a void string to differentiate no
* media attribute from an empty one.
* @param aResult A reference to store the resulting URL spec in if we
* selected a source. This value is not guaranteed to parse to
* a valid URL, merely the URL that the tag would attempt to
* resolve and load (which may be the empty string). This
* parameter is not modified if return value is false.
* @return True if we were able to select a final source, false if further
* sources would be considered. It follows that this always returns
* true if !aIsSourceTag.
*
* Note that the return value may be true with an empty string as the result,
* which implies that the parameters provided describe a tag that would select
* no source. This is distinct from a return of false which implies that
* further <source> or <img> tags would be considered.
*/
static bool
SelectSourceForTagWithAttrs(nsIDocument *aDocument,
bool aIsSourceTag,
const nsAString& aSrcAttr,
const nsAString& aSrcsetAttr,
const nsAString& aSizesAttr,
const nsAString& aTypeAttr,
const nsAString& aMediaAttr,
nsAString& aResult);
/**
* If this image's src pointers to an SVG document, flush the SVG document's
* use counters to telemetry. Only used for testing purposes.
*/
void FlushUseCounters();
protected:
virtual ~HTMLImageElement();
// Queues a task to run LoadSelectedImage pending stable state.
//
// Pending Bug 1076583 this is only used by the responsive image
// algorithm (InResponsiveMode()) -- synchronous actions when just
// using img.src will bypass this, and update source and kick off
// image load synchronously.
void QueueImageLoadTask(bool aAlwaysLoad);
// True if we have a srcset attribute or a <picture> parent, regardless of if
// any valid responsive sources were parsed from either.
bool HaveSrcsetOrInPicture();
// True if we are using the newer image loading algorithm. This will be the
// only mode after Bug 1076583
bool InResponsiveMode();
// Resolve and load the current mResponsiveSelector (responsive mode) or src
// attr image.
nsresult LoadSelectedImage(bool aForce, bool aNotify, bool aAlwaysLoad);
// True if this string represents a type we would support on <source type>
static bool SupportedPictureSourceType(const nsAString& aType);
// Update/create/destroy mResponsiveSelector
void PictureSourceSrcsetChanged(nsIContent *aSourceNode,
const nsAString& aNewValue, bool aNotify);
void PictureSourceSizesChanged(nsIContent *aSourceNode,
const nsAString& aNewValue, bool aNotify);
// As we re-run the source selection on these mutations regardless,
// we don't actually care which changed or to what
void PictureSourceMediaOrTypeChanged(nsIContent *aSourceNode, bool aNotify);
void PictureSourceAdded(nsIContent *aSourceNode);
// This should be called prior to the unbind, such that nextsibling works
void PictureSourceRemoved(nsIContent *aSourceNode);
// Re-evaluates all source nodes (picture <source>,<img>) and finds
// the best source set for mResponsiveSelector. If a better source
// is found, creates a new selector and feeds the source to it. If
// the current ResponsiveSelector is not changed, runs
// SelectImage(true) to re-evaluate its candidates.
//
// Because keeping the existing selector is the common case (and we
// often do no-op reselections), this does not re-parse values for
// the existing mResponsiveSelector, meaning you need to update its
// parameters as appropriate before calling (or null it out to force
// recreation)
//
// Returns true if the source has changed, and false otherwise.
bool UpdateResponsiveSource();
// Given a <source> node that is a previous sibling *or* ourselves, try to
// create a ResponsiveSelector.
// If the node's srcset/sizes make for an invalid selector, returns
// false. This does not guarantee the resulting selector matches an image,
// only that it is valid.
bool TryCreateResponsiveSelector(nsIContent *aSourceNode,
const nsAString *aSrcset = nullptr,
const nsAString *aSizes = nullptr);
CSSIntPoint GetXY();
virtual void GetItemValueText(DOMString& text) override;
virtual void SetItemValueText(const nsAString& text) override;
virtual JSObject* WrapNode(JSContext *aCx, JS::Handle<JSObject*> aGivenProto) override;
void UpdateFormOwner();
virtual nsresult BeforeSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
nsAttrValueOrString* aValue,
bool aNotify) override;
virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
const nsAttrValue* aValue, bool aNotify) override;
// This is a weak reference that this element and the HTMLFormElement
// cooperate in maintaining.
HTMLFormElement* mForm;
// Created when we're tracking responsive image state
RefPtr<ResponsiveImageSelector> mResponsiveSelector;
private:
bool SourceElementMatches(nsIContent* aSourceNode);
static void MapAttributesIntoRule(const nsMappedAttributes* aAttributes,
nsRuleData* aData);
bool mInDocResponsiveContent;
RefPtr<ImageLoadTask> mPendingImageLoadTask;
};
} // namespace dom
} // namespace mozilla
#endif /* mozilla_dom_HTMLImageElement_h */