1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/accessible/src/base/AccEvent.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,526 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#ifndef _AccEvent_H_
1.10 +#define _AccEvent_H_
1.11 +
1.12 +#include "nsIAccessibleEvent.h"
1.13 +
1.14 +#include "mozilla/a11y/Accessible.h"
1.15 +
1.16 +namespace mozilla {
1.17 +
1.18 +namespace dom {
1.19 +class Selection;
1.20 +}
1.21 +
1.22 +namespace a11y {
1.23 +
1.24 +class DocAccessible;
1.25 +
1.26 +// Constants used to point whether the event is from user input.
1.27 +enum EIsFromUserInput
1.28 +{
1.29 + // eNoUserInput: event is not from user input
1.30 + eNoUserInput = 0,
1.31 + // eFromUserInput: event is from user input
1.32 + eFromUserInput = 1,
1.33 + // eAutoDetect: the value should be obtained from event state manager
1.34 + eAutoDetect = -1
1.35 +};
1.36 +
1.37 +/**
1.38 + * Generic accessible event.
1.39 + */
1.40 +class AccEvent
1.41 +{
1.42 +public:
1.43 +
1.44 + // Rule for accessible events.
1.45 + // The rule will be applied when flushing pending events.
1.46 + enum EEventRule {
1.47 + // eAllowDupes : More than one event of the same type is allowed.
1.48 + // This event will always be emitted. This flag is used for events that
1.49 + // don't support coalescence.
1.50 + eAllowDupes,
1.51 +
1.52 + // eCoalesceReorder : For reorder events from the same subtree or the same
1.53 + // node, only the umbrella event on the ancestor will be emitted.
1.54 + eCoalesceReorder,
1.55 +
1.56 + // eCoalesceMutationTextChange : coalesce text change events caused by
1.57 + // tree mutations of the same tree level.
1.58 + eCoalesceMutationTextChange,
1.59 +
1.60 + // eCoalesceOfSameType : For events of the same type, only the newest event
1.61 + // will be processed.
1.62 + eCoalesceOfSameType,
1.63 +
1.64 + // eCoalesceSelectionChange: coalescence of selection change events.
1.65 + eCoalesceSelectionChange,
1.66 +
1.67 + // eCoalesceStateChange: coalesce state change events.
1.68 + eCoalesceStateChange,
1.69 +
1.70 + // eCoalesceTextSelChange: coalescence of text selection change events.
1.71 + eCoalesceTextSelChange,
1.72 +
1.73 + // eRemoveDupes : For repeat events, only the newest event in queue
1.74 + // will be emitted.
1.75 + eRemoveDupes,
1.76 +
1.77 + // eDoNotEmit : This event is confirmed as a duplicate, do not emit it.
1.78 + eDoNotEmit
1.79 + };
1.80 +
1.81 + // Initialize with an nsIAccessible
1.82 + AccEvent(uint32_t aEventType, Accessible* aAccessible,
1.83 + EIsFromUserInput aIsFromUserInput = eAutoDetect,
1.84 + EEventRule aEventRule = eRemoveDupes);
1.85 + virtual ~AccEvent() {}
1.86 +
1.87 + // AccEvent
1.88 + uint32_t GetEventType() const { return mEventType; }
1.89 + EEventRule GetEventRule() const { return mEventRule; }
1.90 + bool IsFromUserInput() const { return mIsFromUserInput; }
1.91 + EIsFromUserInput FromUserInput() const
1.92 + { return static_cast<EIsFromUserInput>(mIsFromUserInput); }
1.93 +
1.94 + Accessible* GetAccessible() const { return mAccessible; }
1.95 + DocAccessible* GetDocAccessible() const { return mAccessible->Document(); }
1.96 +
1.97 + /**
1.98 + * Down casting.
1.99 + */
1.100 + enum EventGroup {
1.101 + eGenericEvent,
1.102 + eStateChangeEvent,
1.103 + eTextChangeEvent,
1.104 + eMutationEvent,
1.105 + eReorderEvent,
1.106 + eHideEvent,
1.107 + eShowEvent,
1.108 + eCaretMoveEvent,
1.109 + eTextSelChangeEvent,
1.110 + eSelectionChangeEvent,
1.111 + eTableChangeEvent,
1.112 + eVirtualCursorChangeEvent
1.113 + };
1.114 +
1.115 + static const EventGroup kEventGroup = eGenericEvent;
1.116 + virtual unsigned int GetEventGroups() const
1.117 + {
1.118 + return 1U << eGenericEvent;
1.119 + }
1.120 +
1.121 + /**
1.122 + * Reference counting and cycle collection.
1.123 + */
1.124 + NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(AccEvent)
1.125 + NS_DECL_CYCLE_COLLECTION_NATIVE_CLASS(AccEvent)
1.126 +
1.127 +protected:
1.128 + bool mIsFromUserInput;
1.129 + uint32_t mEventType;
1.130 + EEventRule mEventRule;
1.131 + nsRefPtr<Accessible> mAccessible;
1.132 +
1.133 + friend class EventQueue;
1.134 + friend class AccReorderEvent;
1.135 +};
1.136 +
1.137 +
1.138 +/**
1.139 + * Accessible state change event.
1.140 + */
1.141 +class AccStateChangeEvent: public AccEvent
1.142 +{
1.143 +public:
1.144 + AccStateChangeEvent(Accessible* aAccessible, uint64_t aState,
1.145 + bool aIsEnabled,
1.146 + EIsFromUserInput aIsFromUserInput = eAutoDetect) :
1.147 + AccEvent(nsIAccessibleEvent::EVENT_STATE_CHANGE, aAccessible,
1.148 + aIsFromUserInput, eCoalesceStateChange),
1.149 + mState(aState), mIsEnabled(aIsEnabled) { }
1.150 +
1.151 + AccStateChangeEvent(Accessible* aAccessible, uint64_t aState) :
1.152 + AccEvent(::nsIAccessibleEvent::EVENT_STATE_CHANGE, aAccessible,
1.153 + eAutoDetect, eCoalesceStateChange), mState(aState)
1.154 + { mIsEnabled = (mAccessible->State() & mState) != 0; }
1.155 +
1.156 + // AccEvent
1.157 + static const EventGroup kEventGroup = eStateChangeEvent;
1.158 + virtual unsigned int GetEventGroups() const
1.159 + {
1.160 + return AccEvent::GetEventGroups() | (1U << eStateChangeEvent);
1.161 + }
1.162 +
1.163 + // AccStateChangeEvent
1.164 + uint64_t GetState() const { return mState; }
1.165 + bool IsStateEnabled() const { return mIsEnabled; }
1.166 +
1.167 +private:
1.168 + uint64_t mState;
1.169 + bool mIsEnabled;
1.170 +
1.171 + friend class EventQueue;
1.172 +};
1.173 +
1.174 +
1.175 +/**
1.176 + * Accessible text change event.
1.177 + */
1.178 +class AccTextChangeEvent: public AccEvent
1.179 +{
1.180 +public:
1.181 + AccTextChangeEvent(Accessible* aAccessible, int32_t aStart,
1.182 + const nsAString& aModifiedText, bool aIsInserted,
1.183 + EIsFromUserInput aIsFromUserInput = eAutoDetect);
1.184 +
1.185 + // AccEvent
1.186 + static const EventGroup kEventGroup = eTextChangeEvent;
1.187 + virtual unsigned int GetEventGroups() const
1.188 + {
1.189 + return AccEvent::GetEventGroups() | (1U << eTextChangeEvent);
1.190 + }
1.191 +
1.192 + // AccTextChangeEvent
1.193 + int32_t GetStartOffset() const { return mStart; }
1.194 + uint32_t GetLength() const { return mModifiedText.Length(); }
1.195 + bool IsTextInserted() const { return mIsInserted; }
1.196 + void GetModifiedText(nsAString& aModifiedText)
1.197 + { aModifiedText = mModifiedText; }
1.198 +
1.199 +private:
1.200 + int32_t mStart;
1.201 + bool mIsInserted;
1.202 + nsString mModifiedText;
1.203 +
1.204 + friend class EventQueue;
1.205 + friend class AccReorderEvent;
1.206 +};
1.207 +
1.208 +
1.209 +/**
1.210 + * Base class for show and hide accessible events.
1.211 + */
1.212 +class AccMutationEvent: public AccEvent
1.213 +{
1.214 +public:
1.215 + AccMutationEvent(uint32_t aEventType, Accessible* aTarget,
1.216 + nsINode* aTargetNode) :
1.217 + AccEvent(aEventType, aTarget, eAutoDetect, eCoalesceMutationTextChange)
1.218 + {
1.219 + // Don't coalesce these since they are coalesced by reorder event. Coalesce
1.220 + // contained text change events.
1.221 + mParent = mAccessible->Parent();
1.222 + }
1.223 + virtual ~AccMutationEvent() { }
1.224 +
1.225 + // Event
1.226 + static const EventGroup kEventGroup = eMutationEvent;
1.227 + virtual unsigned int GetEventGroups() const
1.228 + {
1.229 + return AccEvent::GetEventGroups() | (1U << eMutationEvent);
1.230 + }
1.231 +
1.232 + // MutationEvent
1.233 + bool IsShow() const { return mEventType == nsIAccessibleEvent::EVENT_SHOW; }
1.234 + bool IsHide() const { return mEventType == nsIAccessibleEvent::EVENT_HIDE; }
1.235 +
1.236 +protected:
1.237 + nsCOMPtr<nsINode> mNode;
1.238 + nsRefPtr<Accessible> mParent;
1.239 + nsRefPtr<AccTextChangeEvent> mTextChangeEvent;
1.240 +
1.241 + friend class EventQueue;
1.242 +};
1.243 +
1.244 +
1.245 +/**
1.246 + * Accessible hide event.
1.247 + */
1.248 +class AccHideEvent: public AccMutationEvent
1.249 +{
1.250 +public:
1.251 + AccHideEvent(Accessible* aTarget, nsINode* aTargetNode);
1.252 +
1.253 + // Event
1.254 + static const EventGroup kEventGroup = eHideEvent;
1.255 + virtual unsigned int GetEventGroups() const
1.256 + {
1.257 + return AccMutationEvent::GetEventGroups() | (1U << eHideEvent);
1.258 + }
1.259 +
1.260 + // AccHideEvent
1.261 + Accessible* TargetParent() const { return mParent; }
1.262 + Accessible* TargetNextSibling() const { return mNextSibling; }
1.263 + Accessible* TargetPrevSibling() const { return mPrevSibling; }
1.264 +
1.265 +protected:
1.266 + nsRefPtr<Accessible> mNextSibling;
1.267 + nsRefPtr<Accessible> mPrevSibling;
1.268 +
1.269 + friend class EventQueue;
1.270 +};
1.271 +
1.272 +
1.273 +/**
1.274 + * Accessible show event.
1.275 + */
1.276 +class AccShowEvent: public AccMutationEvent
1.277 +{
1.278 +public:
1.279 + AccShowEvent(Accessible* aTarget, nsINode* aTargetNode);
1.280 +
1.281 + // Event
1.282 + static const EventGroup kEventGroup = eShowEvent;
1.283 + virtual unsigned int GetEventGroups() const
1.284 + {
1.285 + return AccMutationEvent::GetEventGroups() | (1U << eShowEvent);
1.286 + }
1.287 +};
1.288 +
1.289 +
1.290 +/**
1.291 + * Class for reorder accessible event. Takes care about
1.292 + */
1.293 +class AccReorderEvent : public AccEvent
1.294 +{
1.295 +public:
1.296 + AccReorderEvent(Accessible* aTarget) :
1.297 + AccEvent(::nsIAccessibleEvent::EVENT_REORDER, aTarget,
1.298 + eAutoDetect, eCoalesceReorder) { }
1.299 + virtual ~AccReorderEvent() { }
1.300 +
1.301 + // Event
1.302 + static const EventGroup kEventGroup = eReorderEvent;
1.303 + virtual unsigned int GetEventGroups() const
1.304 + {
1.305 + return AccEvent::GetEventGroups() | (1U << eReorderEvent);
1.306 + }
1.307 +
1.308 + /**
1.309 + * Get connected with mutation event.
1.310 + */
1.311 + void AddSubMutationEvent(AccMutationEvent* aEvent)
1.312 + { mDependentEvents.AppendElement(aEvent); }
1.313 +
1.314 + /**
1.315 + * Do not emit the reorder event and its connected mutation events.
1.316 + */
1.317 + void DoNotEmitAll()
1.318 + {
1.319 + mEventRule = AccEvent::eDoNotEmit;
1.320 + uint32_t eventsCount = mDependentEvents.Length();
1.321 + for (uint32_t idx = 0; idx < eventsCount; idx++)
1.322 + mDependentEvents[idx]->mEventRule = AccEvent::eDoNotEmit;
1.323 + }
1.324 +
1.325 + /**
1.326 + * Return true if the given accessible is a target of connected mutation
1.327 + * event.
1.328 + */
1.329 + uint32_t IsShowHideEventTarget(const Accessible* aTarget) const;
1.330 +
1.331 +protected:
1.332 + /**
1.333 + * Show and hide events causing this reorder event.
1.334 + */
1.335 + nsTArray<AccMutationEvent*> mDependentEvents;
1.336 +
1.337 + friend class EventQueue;
1.338 +};
1.339 +
1.340 +
1.341 +/**
1.342 + * Accessible caret move event.
1.343 + */
1.344 +class AccCaretMoveEvent: public AccEvent
1.345 +{
1.346 +public:
1.347 + AccCaretMoveEvent(Accessible* aAccessible, int32_t aCaretOffset,
1.348 + EIsFromUserInput aIsFromUserInput = eAutoDetect) :
1.349 + AccEvent(::nsIAccessibleEvent::EVENT_TEXT_CARET_MOVED, aAccessible,
1.350 + aIsFromUserInput),
1.351 + mCaretOffset(aCaretOffset) { }
1.352 + virtual ~AccCaretMoveEvent() { }
1.353 +
1.354 + // AccEvent
1.355 + static const EventGroup kEventGroup = eCaretMoveEvent;
1.356 + virtual unsigned int GetEventGroups() const
1.357 + {
1.358 + return AccEvent::GetEventGroups() | (1U << eCaretMoveEvent);
1.359 + }
1.360 +
1.361 + // AccCaretMoveEvent
1.362 + int32_t GetCaretOffset() const { return mCaretOffset; }
1.363 +
1.364 +private:
1.365 + int32_t mCaretOffset;
1.366 +};
1.367 +
1.368 +
1.369 +/**
1.370 + * Accessible text selection change event.
1.371 + */
1.372 +class AccTextSelChangeEvent : public AccEvent
1.373 +{
1.374 +public:
1.375 + AccTextSelChangeEvent(HyperTextAccessible* aTarget,
1.376 + dom::Selection* aSelection,
1.377 + int32_t aReason);
1.378 + virtual ~AccTextSelChangeEvent();
1.379 +
1.380 + // AccEvent
1.381 + static const EventGroup kEventGroup = eTextSelChangeEvent;
1.382 + virtual unsigned int GetEventGroups() const
1.383 + {
1.384 + return AccEvent::GetEventGroups() | (1U << eTextSelChangeEvent);
1.385 + }
1.386 +
1.387 + // AccTextSelChangeEvent
1.388 +
1.389 + /**
1.390 + * Return true if the text selection change wasn't caused by pure caret move.
1.391 + */
1.392 + bool IsCaretMoveOnly() const;
1.393 +
1.394 +private:
1.395 + nsRefPtr<dom::Selection> mSel;
1.396 + int32_t mReason;
1.397 +
1.398 + friend class EventQueue;
1.399 + friend class SelectionManager;
1.400 +};
1.401 +
1.402 +
1.403 +/**
1.404 + * Accessible widget selection change event.
1.405 + */
1.406 +class AccSelChangeEvent : public AccEvent
1.407 +{
1.408 +public:
1.409 + enum SelChangeType {
1.410 + eSelectionAdd,
1.411 + eSelectionRemove
1.412 + };
1.413 +
1.414 + AccSelChangeEvent(Accessible* aWidget, Accessible* aItem,
1.415 + SelChangeType aSelChangeType);
1.416 +
1.417 + virtual ~AccSelChangeEvent() { }
1.418 +
1.419 + // AccEvent
1.420 + static const EventGroup kEventGroup = eSelectionChangeEvent;
1.421 + virtual unsigned int GetEventGroups() const
1.422 + {
1.423 + return AccEvent::GetEventGroups() | (1U << eSelectionChangeEvent);
1.424 + }
1.425 +
1.426 + // AccSelChangeEvent
1.427 + Accessible* Widget() const { return mWidget; }
1.428 +
1.429 +private:
1.430 + nsRefPtr<Accessible> mWidget;
1.431 + nsRefPtr<Accessible> mItem;
1.432 + SelChangeType mSelChangeType;
1.433 + uint32_t mPreceedingCount;
1.434 + AccSelChangeEvent* mPackedEvent;
1.435 +
1.436 + friend class EventQueue;
1.437 +};
1.438 +
1.439 +
1.440 +/**
1.441 + * Accessible table change event.
1.442 + */
1.443 +class AccTableChangeEvent : public AccEvent
1.444 +{
1.445 +public:
1.446 + AccTableChangeEvent(Accessible* aAccessible, uint32_t aEventType,
1.447 + int32_t aRowOrColIndex, int32_t aNumRowsOrCols);
1.448 +
1.449 + // AccEvent
1.450 + static const EventGroup kEventGroup = eTableChangeEvent;
1.451 + virtual unsigned int GetEventGroups() const
1.452 + {
1.453 + return AccEvent::GetEventGroups() | (1U << eTableChangeEvent);
1.454 + }
1.455 +
1.456 + // AccTableChangeEvent
1.457 + uint32_t GetIndex() const { return mRowOrColIndex; }
1.458 + uint32_t GetCount() const { return mNumRowsOrCols; }
1.459 +
1.460 +private:
1.461 + uint32_t mRowOrColIndex; // the start row/column after which the rows are inserted/deleted.
1.462 + uint32_t mNumRowsOrCols; // the number of inserted/deleted rows/columns
1.463 +};
1.464 +
1.465 +/**
1.466 + * Accessible virtual cursor change event.
1.467 + */
1.468 +class AccVCChangeEvent : public AccEvent
1.469 +{
1.470 +public:
1.471 + AccVCChangeEvent(Accessible* aAccessible,
1.472 + nsIAccessible* aOldAccessible,
1.473 + int32_t aOldStart, int32_t aOldEnd,
1.474 + int16_t aReason);
1.475 +
1.476 + virtual ~AccVCChangeEvent() { }
1.477 +
1.478 + // AccEvent
1.479 + static const EventGroup kEventGroup = eVirtualCursorChangeEvent;
1.480 + virtual unsigned int GetEventGroups() const
1.481 + {
1.482 + return AccEvent::GetEventGroups() | (1U << eVirtualCursorChangeEvent);
1.483 + }
1.484 +
1.485 + // AccTableChangeEvent
1.486 + nsIAccessible* OldAccessible() const { return mOldAccessible; }
1.487 + int32_t OldStartOffset() const { return mOldStart; }
1.488 + int32_t OldEndOffset() const { return mOldEnd; }
1.489 + int32_t Reason() const { return mReason; }
1.490 +
1.491 +private:
1.492 + nsRefPtr<nsIAccessible> mOldAccessible;
1.493 + int32_t mOldStart;
1.494 + int32_t mOldEnd;
1.495 + int16_t mReason;
1.496 +};
1.497 +
1.498 +/**
1.499 + * Downcast the generic accessible event object to derived type.
1.500 + */
1.501 +class downcast_accEvent
1.502 +{
1.503 +public:
1.504 + downcast_accEvent(AccEvent* e) : mRawPtr(e) { }
1.505 +
1.506 + template<class Destination>
1.507 + operator Destination*() {
1.508 + if (!mRawPtr)
1.509 + return nullptr;
1.510 +
1.511 + return mRawPtr->GetEventGroups() & (1U << Destination::kEventGroup) ?
1.512 + static_cast<Destination*>(mRawPtr) : nullptr;
1.513 + }
1.514 +
1.515 +private:
1.516 + AccEvent* mRawPtr;
1.517 +};
1.518 +
1.519 +/**
1.520 + * Return a new xpcom accessible event for the given internal one.
1.521 + */
1.522 +already_AddRefed<nsIAccessibleEvent>
1.523 +MakeXPCEvent(AccEvent* aEvent);
1.524 +
1.525 +} // namespace a11y
1.526 +} // namespace mozilla
1.527 +
1.528 +#endif
1.529 +
