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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/. */
#ifndef _AccEvent_H_
#define _AccEvent_H_
#include "nsIAccessibleEvent.h"
#include "mozilla/a11y/LocalAccessible.h"
class nsEventShell;
namespace mozilla {
namespace dom {
class Selection;
}
namespace a11y {
class DocAccessible;
class EventQueue;
class TextRange;
// Constants used to point whether the event is from user input.
enum EIsFromUserInput {
// eNoUserInput: event is not from user input
eNoUserInput = 0,
// eFromUserInput: event is from user input
eFromUserInput = 1,
// eAutoDetect: the value should be obtained from event state manager
eAutoDetect = -1
};
/**
* Generic accessible event.
*/
class AccEvent {
public:
// Rule for accessible events.
// The rule will be applied when flushing pending events.
enum EEventRule {
// eAllowDupes : More than one event of the same type is allowed.
// This event will always be emitted. This flag is used for events that
// don't support coalescence.
eAllowDupes,
// eCoalesceReorder : For reorder events from the same subtree or the same
// node, only the umbrella event on the ancestor will be emitted.
eCoalesceReorder,
// eCoalesceOfSameType : For events of the same type, only the newest event
// will be processed.
eCoalesceOfSameType,
// eCoalesceSelectionChange: coalescence of selection change events.
eCoalesceSelectionChange,
// eCoalesceStateChange: coalesce state change events.
eCoalesceStateChange,
// eCoalesceTextSelChange: coalescence of text selection change events.
eCoalesceTextSelChange,
// eRemoveDupes : For repeat events, only the newest event in queue
// will be emitted.
eRemoveDupes,
// eDoNotEmit : This event is confirmed as a duplicate, do not emit it.
eDoNotEmit
};
// Initialize with an accessible.
AccEvent(uint32_t aEventType, LocalAccessible* aAccessible,
EIsFromUserInput aIsFromUserInput = eAutoDetect,
EEventRule aEventRule = eRemoveDupes);
// AccEvent
uint32_t GetEventType() const { return mEventType; }
EEventRule GetEventRule() const { return mEventRule; }
bool IsFromUserInput() const { return mIsFromUserInput; }
EIsFromUserInput FromUserInput() const {
return static_cast<EIsFromUserInput>(mIsFromUserInput);
}
LocalAccessible* GetAccessible() const { return mAccessible; }
DocAccessible* Document() const { return mAccessible->Document(); }
/**
* Down casting.
*/
enum EventGroup {
eGenericEvent,
eStateChangeEvent,
eTextChangeEvent,
eTreeMutationEvent,
eMutationEvent,
eReorderEvent,
eHideEvent,
eShowEvent,
eCaretMoveEvent,
eTextSelChangeEvent,
eSelectionChangeEvent,
eTableChangeEvent,
eVirtualCursorChangeEvent,
eObjectAttrChangedEvent,
eScrollingEvent,
eAnnouncementEvent,
};
static const EventGroup kEventGroup = eGenericEvent;
virtual unsigned int GetEventGroups() const { return 1U << eGenericEvent; }
/**
* Reference counting and cycle collection.
*/
NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(AccEvent)
NS_DECL_CYCLE_COLLECTION_NATIVE_CLASS(AccEvent)
protected:
virtual ~AccEvent() {}
bool mIsFromUserInput;
uint32_t mEventType;
EEventRule mEventRule;
RefPtr<LocalAccessible> mAccessible;
friend class EventQueue;
friend class EventTree;
friend class ::nsEventShell;
friend class NotificationController;
};
/**
* Accessible state change event.
*/
class AccStateChangeEvent : public AccEvent {
public:
AccStateChangeEvent(LocalAccessible* aAccessible, uint64_t aState,
bool aIsEnabled,
EIsFromUserInput aIsFromUserInput = eAutoDetect)
: AccEvent(nsIAccessibleEvent::EVENT_STATE_CHANGE, aAccessible,
aIsFromUserInput, eCoalesceStateChange),
mState(aState),
mIsEnabled(aIsEnabled) {}
AccStateChangeEvent(LocalAccessible* aAccessible, uint64_t aState)
: AccEvent(::nsIAccessibleEvent::EVENT_STATE_CHANGE, aAccessible,
eAutoDetect, eCoalesceStateChange),
mState(aState) {
mIsEnabled = (mAccessible->State() & mState) != 0;
}
// AccEvent
static const EventGroup kEventGroup = eStateChangeEvent;
virtual unsigned int GetEventGroups() const override {
return AccEvent::GetEventGroups() | (1U << eStateChangeEvent);
}
// AccStateChangeEvent
uint64_t GetState() const { return mState; }
bool IsStateEnabled() const { return mIsEnabled; }
private:
uint64_t mState;
bool mIsEnabled;
friend class EventQueue;
};
/**
* Accessible text change event.
*/
class AccTextChangeEvent : public AccEvent {
public:
AccTextChangeEvent(LocalAccessible* aAccessible, int32_t aStart,
const nsAString& aModifiedText, bool aIsInserted,
EIsFromUserInput aIsFromUserInput = eAutoDetect);
// AccEvent
static const EventGroup kEventGroup = eTextChangeEvent;
virtual unsigned int GetEventGroups() const override {
return AccEvent::GetEventGroups() | (1U << eTextChangeEvent);
}
// AccTextChangeEvent
int32_t GetStartOffset() const { return mStart; }
uint32_t GetLength() const { return mModifiedText.Length(); }
bool IsTextInserted() const { return mIsInserted; }
void GetModifiedText(nsAString& aModifiedText) {
aModifiedText = mModifiedText;
}
const nsString& ModifiedText() const { return mModifiedText; }
private:
int32_t mStart;
bool mIsInserted;
nsString mModifiedText;
friend class EventTree;
friend class NotificationController;
};
/**
* A base class for events related to tree mutation, either an AccMutation
* event, or an AccReorderEvent.
*/
class AccTreeMutationEvent : public AccEvent {
public:
AccTreeMutationEvent(uint32_t aEventType, LocalAccessible* aTarget)
: AccEvent(aEventType, aTarget, eAutoDetect, eCoalesceReorder),
mGeneration(0) {}
// Event
static const EventGroup kEventGroup = eTreeMutationEvent;
virtual unsigned int GetEventGroups() const override {
return AccEvent::GetEventGroups() | (1U << eTreeMutationEvent);
}
void SetNextEvent(AccTreeMutationEvent* aNext) { mNextEvent = aNext; }
void SetPrevEvent(AccTreeMutationEvent* aPrev) { mPrevEvent = aPrev; }
AccTreeMutationEvent* NextEvent() const { return mNextEvent; }
AccTreeMutationEvent* PrevEvent() const { return mPrevEvent; }
/**
* A sequence number to know when this event was fired.
*/
uint32_t EventGeneration() const { return mGeneration; }
void SetEventGeneration(uint32_t aGeneration) { mGeneration = aGeneration; }
private:
RefPtr<AccTreeMutationEvent> mNextEvent;
RefPtr<AccTreeMutationEvent> mPrevEvent;
uint32_t mGeneration;
};
/**
* Base class for show and hide accessible events.
*/
class AccMutationEvent : public AccTreeMutationEvent {
public:
AccMutationEvent(uint32_t aEventType, LocalAccessible* aTarget)
: AccTreeMutationEvent(aEventType, aTarget) {
// Don't coalesce these since they are coalesced by reorder event. Coalesce
// contained text change events.
mParent = mAccessible->LocalParent();
}
virtual ~AccMutationEvent() {}
// Event
static const EventGroup kEventGroup = eMutationEvent;
virtual unsigned int GetEventGroups() const override {
return AccTreeMutationEvent::GetEventGroups() | (1U << eMutationEvent);
}
// MutationEvent
bool IsShow() const { return mEventType == nsIAccessibleEvent::EVENT_SHOW; }
bool IsHide() const { return mEventType == nsIAccessibleEvent::EVENT_HIDE; }
LocalAccessible* LocalParent() const { return mParent; }
protected:
nsCOMPtr<nsINode> mNode;
RefPtr<LocalAccessible> mParent;
RefPtr<AccTextChangeEvent> mTextChangeEvent;
friend class EventTree;
friend class NotificationController;
};
/**
* Accessible hide event.
*/
class AccHideEvent : public AccMutationEvent {
public:
explicit AccHideEvent(LocalAccessible* aTarget, bool aNeedsShutdown = true);
// Event
static const EventGroup kEventGroup = eHideEvent;
virtual unsigned int GetEventGroups() const override {
return AccMutationEvent::GetEventGroups() | (1U << eHideEvent);
}
// AccHideEvent
LocalAccessible* TargetParent() const { return mParent; }
LocalAccessible* TargetNextSibling() const { return mNextSibling; }
LocalAccessible* TargetPrevSibling() const { return mPrevSibling; }
bool NeedsShutdown() const { return mNeedsShutdown; }
protected:
bool mNeedsShutdown;
RefPtr<LocalAccessible> mNextSibling;
RefPtr<LocalAccessible> mPrevSibling;
friend class EventTree;
friend class NotificationController;
};
/**
* Accessible show event.
*/
class AccShowEvent : public AccMutationEvent {
public:
explicit AccShowEvent(LocalAccessible* aTarget);
// Event
static const EventGroup kEventGroup = eShowEvent;
virtual unsigned int GetEventGroups() const override {
return AccMutationEvent::GetEventGroups() | (1U << eShowEvent);
}
uint32_t InsertionIndex() const { return mInsertionIndex; }
private:
nsTArray<RefPtr<AccHideEvent>> mPrecedingEvents;
uint32_t mInsertionIndex;
friend class EventTree;
};
/**
* Class for reorder accessible event. Takes care about
*/
class AccReorderEvent : public AccTreeMutationEvent {
public:
explicit AccReorderEvent(LocalAccessible* aTarget)
: AccTreeMutationEvent(::nsIAccessibleEvent::EVENT_REORDER, aTarget) {}
virtual ~AccReorderEvent() {}
// Event
static const EventGroup kEventGroup = eReorderEvent;
virtual unsigned int GetEventGroups() const override {
return AccTreeMutationEvent::GetEventGroups() | (1U << eReorderEvent);
}
};
/**
* Accessible caret move event.
*/
class AccCaretMoveEvent : public AccEvent {
public:
AccCaretMoveEvent(LocalAccessible* aAccessible, int32_t aCaretOffset,
bool aIsSelectionCollapsed, bool aIsAtEndOfLine,
EIsFromUserInput aIsFromUserInput = eAutoDetect)
: AccEvent(::nsIAccessibleEvent::EVENT_TEXT_CARET_MOVED, aAccessible,
aIsFromUserInput),
mCaretOffset(aCaretOffset),
mIsSelectionCollapsed(aIsSelectionCollapsed),
mIsAtEndOfLine(aIsAtEndOfLine) {}
virtual ~AccCaretMoveEvent() {}
// AccEvent
static const EventGroup kEventGroup = eCaretMoveEvent;
virtual unsigned int GetEventGroups() const override {
return AccEvent::GetEventGroups() | (1U << eCaretMoveEvent);
}
// AccCaretMoveEvent
int32_t GetCaretOffset() const { return mCaretOffset; }
bool IsSelectionCollapsed() const { return mIsSelectionCollapsed; }
bool IsAtEndOfLine() { return mIsAtEndOfLine; }
private:
int32_t mCaretOffset;
bool mIsSelectionCollapsed;
bool mIsAtEndOfLine;
};
/**
* Accessible text selection change event.
*/
class AccTextSelChangeEvent : public AccEvent {
public:
AccTextSelChangeEvent(HyperTextAccessible* aTarget,
dom::Selection* aSelection, int32_t aReason);
virtual ~AccTextSelChangeEvent();
// AccEvent
static const EventGroup kEventGroup = eTextSelChangeEvent;
virtual unsigned int GetEventGroups() const override {
return AccEvent::GetEventGroups() | (1U << eTextSelChangeEvent);
}
// AccTextSelChangeEvent
/**
* Return true if the text selection change wasn't caused by pure caret move.
*/
bool IsCaretMoveOnly() const;
/**
* Return selection ranges in document/control.
*/
void SelectionRanges(nsTArray<a11y::TextRange>* aRanges) const;
private:
RefPtr<dom::Selection> mSel;
int32_t mReason;
friend class EventQueue;
friend class SelectionManager;
};
/**
* Accessible widget selection change event.
*/
class AccSelChangeEvent : public AccEvent {
public:
enum SelChangeType { eSelectionAdd, eSelectionRemove };
AccSelChangeEvent(LocalAccessible* aWidget, LocalAccessible* aItem,
SelChangeType aSelChangeType);
virtual ~AccSelChangeEvent() {}
// AccEvent
static const EventGroup kEventGroup = eSelectionChangeEvent;
virtual unsigned int GetEventGroups() const override {
return AccEvent::GetEventGroups() | (1U << eSelectionChangeEvent);
}
// AccSelChangeEvent
LocalAccessible* Widget() const { return mWidget; }
private:
RefPtr<LocalAccessible> mWidget;
RefPtr<LocalAccessible> mItem;
SelChangeType mSelChangeType;
uint32_t mPreceedingCount;
AccSelChangeEvent* mPackedEvent;
friend class EventQueue;
};
/**
* Accessible table change event.
*/
class AccTableChangeEvent : public AccEvent {
public:
AccTableChangeEvent(LocalAccessible* aAccessible, uint32_t aEventType,
int32_t aRowOrColIndex, int32_t aNumRowsOrCols);
// AccEvent
static const EventGroup kEventGroup = eTableChangeEvent;
virtual unsigned int GetEventGroups() const override {
return AccEvent::GetEventGroups() | (1U << eTableChangeEvent);
}
// AccTableChangeEvent
uint32_t GetIndex() const { return mRowOrColIndex; }
uint32_t GetCount() const { return mNumRowsOrCols; }
private:
uint32_t mRowOrColIndex; // the start row/column after which the rows are
// inserted/deleted.
uint32_t mNumRowsOrCols; // the number of inserted/deleted rows/columns
};
/**
* Accessible virtual cursor change event.
*/
class AccVCChangeEvent : public AccEvent {
public:
AccVCChangeEvent(LocalAccessible* aAccessible,
LocalAccessible* aOldAccessible, int32_t aOldStart,
int32_t aOldEnd, LocalAccessible* aNewAccessible,
int32_t aNewStart, int32_t aNewEnd, int16_t aReason,
int16_t aBoundaryType,
EIsFromUserInput aIsFromUserInput = eFromUserInput);
virtual ~AccVCChangeEvent() {}
// AccEvent
static const EventGroup kEventGroup = eVirtualCursorChangeEvent;
virtual unsigned int GetEventGroups() const override {
return AccEvent::GetEventGroups() | (1U << eVirtualCursorChangeEvent);
}
// AccVCChangeEvent
LocalAccessible* OldAccessible() const { return mOldAccessible; }
int32_t OldStartOffset() const { return mOldStart; }
int32_t OldEndOffset() const { return mOldEnd; }
LocalAccessible* NewAccessible() const { return mNewAccessible; }
int32_t NewStartOffset() const { return mNewStart; }
int32_t NewEndOffset() const { return mNewEnd; }
int32_t Reason() const { return mReason; }
int32_t BoundaryType() const { return mBoundaryType; }
private:
RefPtr<LocalAccessible> mOldAccessible;
RefPtr<LocalAccessible> mNewAccessible;
int32_t mOldStart;
int32_t mNewStart;
int32_t mOldEnd;
int32_t mNewEnd;
int16_t mReason;
int16_t mBoundaryType;
};
/**
* Accessible object attribute changed event.
*/
class AccObjectAttrChangedEvent : public AccEvent {
public:
AccObjectAttrChangedEvent(LocalAccessible* aAccessible, nsAtom* aAttribute)
: AccEvent(::nsIAccessibleEvent::EVENT_OBJECT_ATTRIBUTE_CHANGED,
aAccessible),
mAttribute(aAttribute) {}
// AccEvent
static const EventGroup kEventGroup = eObjectAttrChangedEvent;
virtual unsigned int GetEventGroups() const override {
return AccEvent::GetEventGroups() | (1U << eObjectAttrChangedEvent);
}
// AccObjectAttrChangedEvent
nsAtom* GetAttribute() const { return mAttribute; }
private:
RefPtr<nsAtom> mAttribute;
virtual ~AccObjectAttrChangedEvent() {}
};
/**
* Accessible scroll event.
*/
class AccScrollingEvent : public AccEvent {
public:
AccScrollingEvent(uint32_t aEventType, LocalAccessible* aAccessible,
uint32_t aScrollX, uint32_t aScrollY, uint32_t aMaxScrollX,
uint32_t aMaxScrollY)
: AccEvent(aEventType, aAccessible),
mScrollX(aScrollX),
mScrollY(aScrollY),
mMaxScrollX(aMaxScrollX),
mMaxScrollY(aMaxScrollY) {}
virtual ~AccScrollingEvent() {}
// AccEvent
static const EventGroup kEventGroup = eScrollingEvent;
virtual unsigned int GetEventGroups() const override {
return AccEvent::GetEventGroups() | (1U << eScrollingEvent);
}
// The X scrolling offset of the container when the event was fired.
uint32_t ScrollX() { return mScrollX; }
// The Y scrolling offset of the container when the event was fired.
uint32_t ScrollY() { return mScrollY; }
// The max X offset of the container.
uint32_t MaxScrollX() { return mMaxScrollX; }
// The max Y offset of the container.
uint32_t MaxScrollY() { return mMaxScrollY; }
private:
uint32_t mScrollX;
uint32_t mScrollY;
uint32_t mMaxScrollX;
uint32_t mMaxScrollY;
};
/**
* Accessible announcement event.
*/
class AccAnnouncementEvent : public AccEvent {
public:
AccAnnouncementEvent(LocalAccessible* aAccessible,
const nsAString& aAnnouncement, uint16_t aPriority)
: AccEvent(nsIAccessibleEvent::EVENT_ANNOUNCEMENT, aAccessible),
mAnnouncement(aAnnouncement),
mPriority(aPriority) {}
virtual ~AccAnnouncementEvent() {}
// AccEvent
static const EventGroup kEventGroup = eAnnouncementEvent;
virtual unsigned int GetEventGroups() const override {
return AccEvent::GetEventGroups() | (1U << eAnnouncementEvent);
}
const nsString& Announcement() const { return mAnnouncement; }
uint16_t Priority() { return mPriority; }
private:
nsString mAnnouncement;
uint16_t mPriority;
};
/**
* Downcast the generic accessible event object to derived type.
*/
class downcast_accEvent {
public:
explicit downcast_accEvent(AccEvent* e) : mRawPtr(e) {}
template <class Destination>
operator Destination*() {
if (!mRawPtr) return nullptr;
return mRawPtr->GetEventGroups() & (1U << Destination::kEventGroup)
? static_cast<Destination*>(mRawPtr)
: nullptr;
}
private:
AccEvent* mRawPtr;
};
/**
* Return a new xpcom accessible event for the given internal one.
*/
already_AddRefed<nsIAccessibleEvent> MakeXPCEvent(AccEvent* aEvent);
} // namespace a11y
} // namespace mozilla
#endif