gecko-dev/accessible/generic/ImageAccessible.h

90 строки
2.3 KiB
C++

/* -*- 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/. */
#ifndef mozilla_a11y_ImageAccessible_h__
#define mozilla_a11y_ImageAccessible_h__
#include "BaseAccessibles.h"
class nsGenericHTMLElement;
namespace mozilla {
namespace a11y {
/* Accessible for supporting images
* supports:
* - gets name, role
* - support basic state
*/
class ImageAccessible : public LinkableAccessible
{
public:
ImageAccessible(nsIContent* aContent, DocAccessible* aDoc);
// Accessible
virtual a11y::role NativeRole() MOZ_OVERRIDE;
virtual uint64_t NativeState() MOZ_OVERRIDE;
virtual already_AddRefed<nsIPersistentProperties> NativeAttributes() MOZ_OVERRIDE;
// ActionAccessible
virtual uint8_t ActionCount() MOZ_OVERRIDE;
virtual void ActionNameAt(uint8_t aIndex, nsAString& aName) MOZ_OVERRIDE;
virtual bool DoAction(uint8_t aIndex) MOZ_OVERRIDE;
// ImageAccessible
nsIntPoint Position(uint32_t aCoordType);
nsIntSize Size();
protected:
virtual ~ImageAccessible();
// Accessible
virtual ENameValueFlag NativeName(nsString& aName) MOZ_OVERRIDE;
private:
/**
* Return whether the element has a longdesc URI.
*/
bool HasLongDesc() const
{
nsCOMPtr<nsIURI> uri = GetLongDescURI();
return uri;
}
/**
* Return an URI for showlongdesc action if any.
*/
already_AddRefed<nsIURI> GetLongDescURI() const;
/**
* Used by ActionNameAt and DoAction to ensure the index for opening the
* longdesc URL is valid.
* It is always assumed that the highest possible index opens the longdesc.
* This doesn't check that there is actually a longdesc, just that the index
* would be correct if there was one.
*
* @param aIndex The 0-based index to be tested.
*
* @returns true if index is valid for longdesc action.
*/
inline bool IsLongDescIndex(uint8_t aIndex);
};
////////////////////////////////////////////////////////////////////////////////
// Accessible downcasting method
inline ImageAccessible*
Accessible::AsImage()
{
return IsImage() ? static_cast<ImageAccessible*>(this) : nullptr;
}
} // namespace a11y
} // namespace mozilla
#endif