/* -*- 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,
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:
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)
: AccMutationEvent(::nsIAccessibleEvent::EVENT_SHOW, aTarget) {}
// Event
static const EventGroup kEventGroup = eShowEvent;
virtual unsigned int GetEventGroups()
const override {
return AccMutationEvent::GetEventGroups() | (1U << eShowEvent);
}
};
/**
* 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);
}
/*
* Make this an inner reorder event that is coalesced into
* a reorder event of an ancestor.
*/
void SetInner() { mEventType = ::nsIAccessibleEvent::EVENT_INNER_REORDER; }
};
/**
* Accessible caret move event.
*/
class AccCaretMoveEvent :
public AccEvent {
public:
AccCaretMoveEvent(LocalAccessible* aAccessible, int32_t aCaretOffset,
bool aIsSelectionCollapsed,
bool aIsAtEndOfLine,
int32_t aGranularity,
EIsFromUserInput aIsFromUserInput = eAutoDetect)
: AccEvent(::nsIAccessibleEvent::EVENT_TEXT_CARET_MOVED, aAccessible,
aIsFromUserInput),
mCaretOffset(aCaretOffset),
mIsSelectionCollapsed(aIsSelectionCollapsed),
mIsAtEndOfLine(aIsAtEndOfLine),
mGranularity(aGranularity) {}
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; }
int32_t GetGranularity()
const {
return mGranularity; }
private:
int32_t mCaretOffset;
bool mIsSelectionCollapsed;
bool mIsAtEndOfLine;
int32_t mGranularity;
};
/**
* Accessible text selection change event.
*/
class AccTextSelChangeEvent :
public AccEvent {
public:
AccTextSelChangeEvent(HyperTextAccessible* aTarget,
dom::Selection* aSelection, int32_t aReason,
int32_t aGranularity);
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;
int32_t GetGranularity()
const {
return mGranularity; }
/**
* Return selection ranges in document/control.
*/
void SelectionRanges(nsTArray<a11y::TextRange>* aRanges)
const;
private:
RefPtr<dom::Selection> mSel;
int32_t mReason;
int32_t mGranularity;
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 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
