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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=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
#ifndef mozilla_a11y_AccIterator_h__
#define mozilla_a11y_AccIterator_h__
#include "Filters.h"
#include "mozilla/a11y/DocAccessible.h"
#include "nsTArray.h"
#include <memory>
class nsITreeView;
namespace mozilla {
namespace dom {
class Element;
}
namespace a11y {
class DocAccessibleParent;
/**
* AccIterable is a basic interface for iterators over accessibles.
*/
class AccIterable {
public:
virtual ~AccIterable() {}
virtual Accessible* Next() = 0;
private:
friend class Relation;
std::unique_ptr<AccIterable> mNextIter;
};
/**
* Allows to iterate through accessible children or subtree complying with
* filter function.
*/
class AccIterator : public AccIterable {
public:
AccIterator(const LocalAccessible* aRoot, filters::FilterFuncPtr aFilterFunc);
virtual ~AccIterator();
/**
* Return next accessible complying with filter function. Return the first
* accessible for the first time.
*/
virtual LocalAccessible* Next() override;
private:
AccIterator();
AccIterator(const AccIterator&);
AccIterator& operator=(const AccIterator&);
struct IteratorState {
explicit IteratorState(const LocalAccessible* aParent,
IteratorState* mParentState = nullptr);
const LocalAccessible* mParent;
int32_t mIndex;
IteratorState* mParentState;
};
filters::FilterFuncPtr mFilterFunc;
IteratorState* mState;
};
/**
* Allows to traverse through related accessibles that are pointing to the given
* dependent accessible by relation attribute. This is typically used to query
* implicit reverse relations; e.g. calculating the LABEL_FOR relation for a
* label where that label was referenced using aria-labelledby.
*/
class RelatedAccIterator : public AccIterable {
public:
/**
* Constructor.
*
* @param aDocument [in] the document accessible the related
* & accessibles belong to.
* @param aDependentContent [in] the content of dependent accessible that
* relations were requested for
* @param aRelAttr [in] relation attribute that relations are
* pointed by, null for all relations
*/
RelatedAccIterator(DocAccessible* aDocument, nsIContent* aDependentContent,
nsAtom* aRelAttr);
virtual ~RelatedAccIterator() {}
/**
* Return next related accessible for the given dependent accessible.
*/
virtual LocalAccessible* Next() override;
private:
RelatedAccIterator();
RelatedAccIterator(const RelatedAccIterator&);
RelatedAccIterator& operator=(const RelatedAccIterator&);
DocAccessible* mDocument;
nsIContent* mDependentContent;
nsAtom* mRelAttr;
DocAccessible::AttrRelProviders* mProviders;
uint32_t mIndex;
bool mIsWalkingDependentElements;
};
/**
* Used to iterate through HTML labels associated with the given accessible.
*/
class HTMLLabelIterator : public AccIterable {
public:
enum LabelFilter { eAllLabels, eSkipAncestorLabel };
HTMLLabelIterator(DocAccessible* aDocument,
const LocalAccessible* aAccessible,
LabelFilter aFilter = eAllLabels);
virtual ~HTMLLabelIterator() {}
/**
* Return next label accessible associated with the given element.
*/
virtual LocalAccessible* Next() override;
private:
HTMLLabelIterator();
HTMLLabelIterator(const HTMLLabelIterator&);
HTMLLabelIterator& operator=(const HTMLLabelIterator&);
bool IsLabel(LocalAccessible* aLabel);
RelatedAccIterator mRelIter;
// pointer now because iterators life cycle is short.
const LocalAccessible* mAcc;
LabelFilter mLabelFilter;
};
/**
* Used to iterate through HTML outputs associated with the given element.
*/
class HTMLOutputIterator : public AccIterable {
public:
HTMLOutputIterator(DocAccessible* aDocument, nsIContent* aElement);
virtual ~HTMLOutputIterator() {}
/**
* Return next output accessible associated with the given element.
*/
virtual LocalAccessible* Next() override;
private:
HTMLOutputIterator();
HTMLOutputIterator(const HTMLOutputIterator&);
HTMLOutputIterator& operator=(const HTMLOutputIterator&);
RelatedAccIterator mRelIter;
};
/**
* Used to iterate through XUL labels associated with the given element.
*/
class XULLabelIterator : public AccIterable {
public:
XULLabelIterator(DocAccessible* aDocument, nsIContent* aElement);
virtual ~XULLabelIterator() {}
/**
* Return next label accessible associated with the given element.
*/
virtual LocalAccessible* Next() override;
private:
XULLabelIterator();
XULLabelIterator(const XULLabelIterator&);
XULLabelIterator& operator=(const XULLabelIterator&);
RelatedAccIterator mRelIter;
};
/**
* Used to iterate through XUL descriptions associated with the given element.
*/
class XULDescriptionIterator : public AccIterable {
public:
XULDescriptionIterator(DocAccessible* aDocument, nsIContent* aElement);
virtual ~XULDescriptionIterator() {}
/**
* Return next description accessible associated with the given element.
*/
virtual LocalAccessible* Next() override;
private:
XULDescriptionIterator();
XULDescriptionIterator(const XULDescriptionIterator&);
XULDescriptionIterator& operator=(const XULDescriptionIterator&);
RelatedAccIterator mRelIter;
};
/**
* Used to iterate through elements referenced through explicitly set
* attr-elements or IDs listed in a content attribute. Note, any method used to
* iterate through IDs, elements, or accessibles moves iterator to next
* position.
*/
class AssociatedElementsIterator : public AccIterable {
public:
AssociatedElementsIterator(DocAccessible* aDoc, nsIContent* aContent,
nsAtom* aIDRefsAttr);
virtual ~AssociatedElementsIterator() {}
/**
* Return next ID.
*/
const nsDependentSubstring NextID();
/**
* Return next element.
*/
nsIContent* NextElem();
/**
* Return the element with the given ID.
*/
static dom::Element* GetElem(nsIContent* aContent, const nsAString& aID);
dom::Element* GetElem(const nsDependentSubstring& aID);
// AccIterable
virtual LocalAccessible* Next() override;
private:
AssociatedElementsIterator();
AssociatedElementsIterator(const AssociatedElementsIterator&);
AssociatedElementsIterator operator=(const AssociatedElementsIterator&);
nsString mIDs;
nsIContent* mContent;
DocAccessible* mDoc;
nsAString::index_type mCurrIdx;
nsTArray<dom::Element*> mElements;
uint32_t mElemIdx;
};
/**
* Iterator that points to a single accessible returning it on the first call
* to Next().
*/
class SingleAccIterator : public AccIterable {
public:
explicit SingleAccIterator(Accessible* aTarget) : mAcc(aTarget) {}
virtual ~SingleAccIterator() {}
virtual Accessible* Next() override;
private:
SingleAccIterator();
SingleAccIterator(const SingleAccIterator&);
SingleAccIterator& operator=(const SingleAccIterator&);
Accessible* mAcc;
};
/**
* Used to iterate items of the given item container.
*/
class ItemIterator : public AccIterable {
public:
explicit ItemIterator(const Accessible* aItemContainer)
: mContainer(aItemContainer), mAnchor(nullptr) {}
virtual Accessible* Next() override;
private:
ItemIterator() = delete;
ItemIterator(const ItemIterator&) = delete;
ItemIterator& operator=(const ItemIterator&) = delete;
const Accessible* mContainer;
Accessible* mAnchor;
};
/**
* Used to iterate through XUL tree items of the same level.
*/
class XULTreeItemIterator : public AccIterable {
public:
XULTreeItemIterator(const XULTreeAccessible* aXULTree, nsITreeView* aTreeView,
int32_t aRowIdx);
virtual ~XULTreeItemIterator() {}
virtual LocalAccessible* Next() override;
private:
XULTreeItemIterator() = delete;
XULTreeItemIterator(const XULTreeItemIterator&) = delete;
XULTreeItemIterator& operator=(const XULTreeItemIterator&) = delete;
const XULTreeAccessible* mXULTree;
nsITreeView* mTreeView;
int32_t mRowCount;
int32_t mContainerLevel;
int32_t mCurrRowIdx;
};
/**
* Used to iterate through a sequence of RemoteAccessibles supplied as an array
* of ids. Such id arrays are included in the RemoteAccessible cache.
*/
class RemoteAccIterator : public AccIterable {
public:
/**
* Construct with a reference to an array owned somewhere else; e.g. a
* RemoteAccessible cache.
*/
RemoteAccIterator(const nsTArray<uint64_t>& aIds, DocAccessibleParent* aDoc)
: mIds(aIds), mDoc(aDoc), mIndex(0) {}
virtual ~RemoteAccIterator() = default;
virtual Accessible* Next() override;
private:
const nsTArray<uint64_t>& mIds;
DocAccessibleParent* mDoc;
uint32_t mIndex;
};
} // namespace a11y
} // namespace mozilla
#endif