gecko-dev/accessible/base/FocusManager.h

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3.6 KiB
C++

/* 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_FocusManager_h_
#define mozilla_a11y_FocusManager_h_
#include "mozilla/RefPtr.h"
class nsINode;
class nsISupports;
namespace mozilla {
namespace dom {
class Document;
}
namespace a11y {
class AccEvent;
class Accessible;
class DocAccessible;
/**
* Manage the accessible focus. Used to fire and process accessible events.
*/
class FocusManager {
public:
virtual ~FocusManager();
/**
* Return a focused accessible.
*/
Accessible* FocusedAccessible() const;
/**
* Return true if given accessible is focused.
*/
bool IsFocused(const Accessible* aAccessible) const;
/**
* Return true if the given accessible is an active item, i.e. an item that
* is current within the active widget.
*/
inline bool IsActiveItem(const Accessible* aAccessible) {
return aAccessible == mActiveItem;
}
/**
* Return DOM node having DOM focus.
*/
nsINode* FocusedDOMNode() const;
/**
* Return true if given DOM node has DOM focus.
*/
inline bool HasDOMFocus(const nsINode* aNode) const {
return aNode == FocusedDOMNode();
}
/**
* Return true if focused accessible is within the given container.
*/
bool IsFocusWithin(const Accessible* aContainer) const;
/**
* Return whether the given accessible is focused or contains the focus or
* contained by focused accessible.
*/
enum FocusDisposition { eNone, eFocused, eContainsFocus, eContainedByFocus };
FocusDisposition IsInOrContainsFocus(const Accessible* aAccessible) const;
/**
* Return true if the given accessible was the last accessible focused.
* This is useful to detect the case where the last focused accessible was
* removed before something else was focused. This can happen in one of two
* ways:
* 1. The DOM focus was removed. DOM doesn't fire a blur event when this
* happens; see bug 559561.
* 2. The accessibility focus was an active item (e.g. aria-activedescendant)
* and that item was removed.
*/
bool WasLastFocused(const Accessible* aAccessible) const;
//////////////////////////////////////////////////////////////////////////////
// Focus notifications and processing (don't use until you know what you do).
/**
* Called when DOM focus event is fired.
*/
void NotifyOfDOMFocus(nsISupports* aTarget);
/**
* Called when DOM blur event is fired.
*/
void NotifyOfDOMBlur(nsISupports* aTarget);
/**
* Called when active item is changed. Note: must be called when accessible
* tree is up to date.
*/
void ActiveItemChanged(Accessible* aItem, bool aCheckIfActive = true);
/**
* Dispatch delayed focus event for the current focus accessible.
*/
void ForceFocusEvent();
/**
* Dispatch delayed focus event for the given target.
*/
void DispatchFocusEvent(DocAccessible* aDocument, Accessible* aTarget);
/**
* Process DOM focus notification.
*/
void ProcessDOMFocus(nsINode* aTarget);
/**
* Process the delayed accessible event.
* do.
*/
void ProcessFocusEvent(AccEvent* aEvent);
protected:
FocusManager();
private:
FocusManager(const FocusManager&);
FocusManager& operator=(const FocusManager&);
/**
* Return DOM document having DOM focus.
*/
dom::Document* FocusedDOMDocument() const;
private:
RefPtr<Accessible> mActiveItem;
RefPtr<Accessible> mLastFocus;
RefPtr<Accessible> mActiveARIAMenubar;
};
} // namespace a11y
} // namespace mozilla
#endif