1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/dom/events/IMEContentObserver.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,566 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* vim: set ts=2 sw=2 et tw=80: */
1.6 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +#include "ContentEventHandler.h"
1.11 +#include "IMEContentObserver.h"
1.12 +#include "mozilla/AsyncEventDispatcher.h"
1.13 +#include "mozilla/EventStateManager.h"
1.14 +#include "mozilla/IMEStateManager.h"
1.15 +#include "mozilla/TextComposition.h"
1.16 +#include "mozilla/dom/Element.h"
1.17 +#include "nsAutoPtr.h"
1.18 +#include "nsContentUtils.h"
1.19 +#include "nsGkAtoms.h"
1.20 +#include "nsIAtom.h"
1.21 +#include "nsIContent.h"
1.22 +#include "nsIDocument.h"
1.23 +#include "nsIDOMDocument.h"
1.24 +#include "nsIDOMRange.h"
1.25 +#include "nsIFrame.h"
1.26 +#include "nsINode.h"
1.27 +#include "nsIPresShell.h"
1.28 +#include "nsISelectionController.h"
1.29 +#include "nsISelectionPrivate.h"
1.30 +#include "nsISupports.h"
1.31 +#include "nsIWidget.h"
1.32 +#include "nsPresContext.h"
1.33 +#include "nsThreadUtils.h"
1.34 +#include "nsWeakReference.h"
1.35 +
1.36 +namespace mozilla {
1.37 +
1.38 +using namespace widget;
1.39 +
1.40 +NS_IMPL_CYCLE_COLLECTION(IMEContentObserver,
1.41 + mWidget, mSelection,
1.42 + mRootContent, mEditableNode, mDocShell)
1.43 +
1.44 +NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(IMEContentObserver)
1.45 + NS_INTERFACE_MAP_ENTRY(nsISelectionListener)
1.46 + NS_INTERFACE_MAP_ENTRY(nsIMutationObserver)
1.47 + NS_INTERFACE_MAP_ENTRY(nsIReflowObserver)
1.48 + NS_INTERFACE_MAP_ENTRY(nsIScrollObserver)
1.49 + NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
1.50 + NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsISelectionListener)
1.51 +NS_INTERFACE_MAP_END
1.52 +
1.53 +NS_IMPL_CYCLE_COLLECTING_ADDREF(IMEContentObserver)
1.54 +NS_IMPL_CYCLE_COLLECTING_RELEASE(IMEContentObserver)
1.55 +
1.56 +IMEContentObserver::IMEContentObserver()
1.57 + : mESM(nullptr)
1.58 +{
1.59 +}
1.60 +
1.61 +void
1.62 +IMEContentObserver::Init(nsIWidget* aWidget,
1.63 + nsPresContext* aPresContext,
1.64 + nsIContent* aContent)
1.65 +{
1.66 + mESM = aPresContext->EventStateManager();
1.67 + mESM->OnStartToObserveContent(this);
1.68 +
1.69 + mWidget = aWidget;
1.70 + mEditableNode = IMEStateManager::GetRootEditableNode(aPresContext, aContent);
1.71 + if (!mEditableNode) {
1.72 + return;
1.73 + }
1.74 +
1.75 + nsIPresShell* presShell = aPresContext->PresShell();
1.76 +
1.77 + // get selection and root content
1.78 + nsCOMPtr<nsISelectionController> selCon;
1.79 + if (mEditableNode->IsNodeOfType(nsINode::eCONTENT)) {
1.80 + nsIFrame* frame =
1.81 + static_cast<nsIContent*>(mEditableNode.get())->GetPrimaryFrame();
1.82 + NS_ENSURE_TRUE_VOID(frame);
1.83 +
1.84 + frame->GetSelectionController(aPresContext,
1.85 + getter_AddRefs(selCon));
1.86 + } else {
1.87 + // mEditableNode is a document
1.88 + selCon = do_QueryInterface(presShell);
1.89 + }
1.90 + NS_ENSURE_TRUE_VOID(selCon);
1.91 +
1.92 + selCon->GetSelection(nsISelectionController::SELECTION_NORMAL,
1.93 + getter_AddRefs(mSelection));
1.94 + NS_ENSURE_TRUE_VOID(mSelection);
1.95 +
1.96 + nsCOMPtr<nsIDOMRange> selDomRange;
1.97 + if (NS_SUCCEEDED(mSelection->GetRangeAt(0, getter_AddRefs(selDomRange)))) {
1.98 + nsRange* selRange = static_cast<nsRange*>(selDomRange.get());
1.99 + NS_ENSURE_TRUE_VOID(selRange && selRange->GetStartParent());
1.100 +
1.101 + mRootContent = selRange->GetStartParent()->
1.102 + GetSelectionRootContent(presShell);
1.103 + } else {
1.104 + mRootContent = mEditableNode->GetSelectionRootContent(presShell);
1.105 + }
1.106 + if (!mRootContent && mEditableNode->IsNodeOfType(nsINode::eDOCUMENT)) {
1.107 + // The document node is editable, but there are no contents, this document
1.108 + // is not editable.
1.109 + return;
1.110 + }
1.111 + NS_ENSURE_TRUE_VOID(mRootContent);
1.112 +
1.113 + if (IMEStateManager::IsTestingIME()) {
1.114 + nsIDocument* doc = aPresContext->Document();
1.115 + (new AsyncEventDispatcher(doc, NS_LITERAL_STRING("MozIMEFocusIn"),
1.116 + false, false))->RunDOMEventWhenSafe();
1.117 + }
1.118 +
1.119 + aWidget->NotifyIME(IMENotification(NOTIFY_IME_OF_FOCUS));
1.120 +
1.121 + // NOTIFY_IME_OF_FOCUS might cause recreating IMEContentObserver
1.122 + // instance via IMEStateManager::UpdateIMEState(). So, this
1.123 + // instance might already have been destroyed, check it.
1.124 + if (!mRootContent) {
1.125 + return;
1.126 + }
1.127 +
1.128 + mDocShell = aPresContext->GetDocShell();
1.129 +
1.130 + ObserveEditableNode();
1.131 +}
1.132 +
1.133 +void
1.134 +IMEContentObserver::ObserveEditableNode()
1.135 +{
1.136 + MOZ_ASSERT(mSelection);
1.137 + MOZ_ASSERT(mRootContent);
1.138 +
1.139 + mUpdatePreference = mWidget->GetIMEUpdatePreference();
1.140 + if (mUpdatePreference.WantSelectionChange()) {
1.141 + // add selection change listener
1.142 + nsCOMPtr<nsISelectionPrivate> selPrivate(do_QueryInterface(mSelection));
1.143 + NS_ENSURE_TRUE_VOID(selPrivate);
1.144 + nsresult rv = selPrivate->AddSelectionListener(this);
1.145 + NS_ENSURE_SUCCESS_VOID(rv);
1.146 + }
1.147 +
1.148 + if (mUpdatePreference.WantTextChange()) {
1.149 + // add text change observer
1.150 + mRootContent->AddMutationObserver(this);
1.151 + }
1.152 +
1.153 + if (mUpdatePreference.WantPositionChanged() && mDocShell) {
1.154 + // Add scroll position listener and reflow observer to detect position and
1.155 + // size changes
1.156 + mDocShell->AddWeakScrollObserver(this);
1.157 + mDocShell->AddWeakReflowObserver(this);
1.158 + }
1.159 +}
1.160 +
1.161 +void
1.162 +IMEContentObserver::Destroy()
1.163 +{
1.164 + // If CreateTextStateManager failed, mRootContent will be null,
1.165 + // and we should not call NotifyIME(IMENotification(NOTIFY_IME_OF_BLUR))
1.166 + if (mRootContent) {
1.167 + if (IMEStateManager::IsTestingIME() && mEditableNode) {
1.168 + nsIDocument* doc = mEditableNode->OwnerDoc();
1.169 + (new AsyncEventDispatcher(doc, NS_LITERAL_STRING("MozIMEFocusOut"),
1.170 + false, false))->RunDOMEventWhenSafe();
1.171 + }
1.172 + mWidget->NotifyIME(IMENotification(NOTIFY_IME_OF_BLUR));
1.173 + }
1.174 + // Even if there are some pending notification, it'll never notify the widget.
1.175 + mWidget = nullptr;
1.176 + if (mUpdatePreference.WantSelectionChange() && mSelection) {
1.177 + nsCOMPtr<nsISelectionPrivate> selPrivate(do_QueryInterface(mSelection));
1.178 + if (selPrivate) {
1.179 + selPrivate->RemoveSelectionListener(this);
1.180 + }
1.181 + }
1.182 + mSelection = nullptr;
1.183 + if (mUpdatePreference.WantTextChange() && mRootContent) {
1.184 + mRootContent->RemoveMutationObserver(this);
1.185 + }
1.186 + if (mUpdatePreference.WantPositionChanged() && mDocShell) {
1.187 + mDocShell->RemoveWeakScrollObserver(this);
1.188 + mDocShell->RemoveWeakReflowObserver(this);
1.189 + }
1.190 + mRootContent = nullptr;
1.191 + mEditableNode = nullptr;
1.192 + mDocShell = nullptr;
1.193 + mUpdatePreference.mWantUpdates = nsIMEUpdatePreference::NOTIFY_NOTHING;
1.194 +
1.195 + if (mESM) {
1.196 + mESM->OnStopObservingContent(this);
1.197 + mESM = nullptr;
1.198 + }
1.199 +}
1.200 +
1.201 +void
1.202 +IMEContentObserver::DisconnectFromEventStateManager()
1.203 +{
1.204 + mESM = nullptr;
1.205 +}
1.206 +
1.207 +bool
1.208 +IMEContentObserver::IsManaging(nsPresContext* aPresContext,
1.209 + nsIContent* aContent)
1.210 +{
1.211 + if (!mSelection || !mRootContent || !mEditableNode) {
1.212 + return false; // failed to initialize.
1.213 + }
1.214 + if (!mRootContent->IsInDoc()) {
1.215 + return false; // the focused editor has already been reframed.
1.216 + }
1.217 + return mEditableNode == IMEStateManager::GetRootEditableNode(aPresContext,
1.218 + aContent);
1.219 +}
1.220 +
1.221 +bool
1.222 +IMEContentObserver::IsEditorHandlingEventForComposition() const
1.223 +{
1.224 + if (!mWidget) {
1.225 + return false;
1.226 + }
1.227 + nsRefPtr<TextComposition> composition =
1.228 + IMEStateManager::GetTextCompositionFor(mWidget);
1.229 + if (!composition) {
1.230 + return false;
1.231 + }
1.232 + return composition->IsEditorHandlingEvent();
1.233 +}
1.234 +
1.235 +nsresult
1.236 +IMEContentObserver::GetSelectionAndRoot(nsISelection** aSelection,
1.237 + nsIContent** aRootContent) const
1.238 +{
1.239 + if (!mEditableNode || !mSelection) {
1.240 + return NS_ERROR_NOT_AVAILABLE;
1.241 + }
1.242 +
1.243 + NS_ASSERTION(mSelection && mRootContent, "uninitialized content observer");
1.244 + NS_ADDREF(*aSelection = mSelection);
1.245 + NS_ADDREF(*aRootContent = mRootContent);
1.246 + return NS_OK;
1.247 +}
1.248 +
1.249 +// Helper class, used for selection change notification
1.250 +class SelectionChangeEvent : public nsRunnable
1.251 +{
1.252 +public:
1.253 + SelectionChangeEvent(IMEContentObserver* aDispatcher,
1.254 + bool aCausedByComposition)
1.255 + : mDispatcher(aDispatcher)
1.256 + , mCausedByComposition(aCausedByComposition)
1.257 + {
1.258 + MOZ_ASSERT(mDispatcher);
1.259 + }
1.260 +
1.261 + NS_IMETHOD Run()
1.262 + {
1.263 + if (mDispatcher->GetWidget()) {
1.264 + IMENotification notification(NOTIFY_IME_OF_SELECTION_CHANGE);
1.265 + notification.mSelectionChangeData.mCausedByComposition =
1.266 + mCausedByComposition;
1.267 + mDispatcher->GetWidget()->NotifyIME(notification);
1.268 + }
1.269 + return NS_OK;
1.270 + }
1.271 +
1.272 +private:
1.273 + nsRefPtr<IMEContentObserver> mDispatcher;
1.274 + bool mCausedByComposition;
1.275 +};
1.276 +
1.277 +nsresult
1.278 +IMEContentObserver::NotifySelectionChanged(nsIDOMDocument* aDOMDocument,
1.279 + nsISelection* aSelection,
1.280 + int16_t aReason)
1.281 +{
1.282 + bool causedByComposition = IsEditorHandlingEventForComposition();
1.283 + if (causedByComposition &&
1.284 + !mUpdatePreference.WantChangesCausedByComposition()) {
1.285 + return NS_OK;
1.286 + }
1.287 +
1.288 + int32_t count = 0;
1.289 + nsresult rv = aSelection->GetRangeCount(&count);
1.290 + NS_ENSURE_SUCCESS(rv, rv);
1.291 + if (count > 0 && mWidget) {
1.292 + nsContentUtils::AddScriptRunner(
1.293 + new SelectionChangeEvent(this, causedByComposition));
1.294 + }
1.295 + return NS_OK;
1.296 +}
1.297 +
1.298 +// Helper class, used for position change notification
1.299 +class PositionChangeEvent MOZ_FINAL : public nsRunnable
1.300 +{
1.301 +public:
1.302 + PositionChangeEvent(IMEContentObserver* aDispatcher)
1.303 + : mDispatcher(aDispatcher)
1.304 + {
1.305 + MOZ_ASSERT(mDispatcher);
1.306 + }
1.307 +
1.308 + NS_IMETHOD Run()
1.309 + {
1.310 + if (mDispatcher->GetWidget()) {
1.311 + mDispatcher->GetWidget()->NotifyIME(
1.312 + IMENotification(NOTIFY_IME_OF_POSITION_CHANGE));
1.313 + }
1.314 + return NS_OK;
1.315 + }
1.316 +
1.317 +private:
1.318 + nsRefPtr<IMEContentObserver> mDispatcher;
1.319 +};
1.320 +
1.321 +void
1.322 +IMEContentObserver::ScrollPositionChanged()
1.323 +{
1.324 + if (mWidget) {
1.325 + nsContentUtils::AddScriptRunner(new PositionChangeEvent(this));
1.326 + }
1.327 +}
1.328 +
1.329 +NS_IMETHODIMP
1.330 +IMEContentObserver::Reflow(DOMHighResTimeStamp aStart,
1.331 + DOMHighResTimeStamp aEnd)
1.332 +{
1.333 + if (mWidget) {
1.334 + nsContentUtils::AddScriptRunner(new PositionChangeEvent(this));
1.335 + }
1.336 + return NS_OK;
1.337 +}
1.338 +
1.339 +NS_IMETHODIMP
1.340 +IMEContentObserver::ReflowInterruptible(DOMHighResTimeStamp aStart,
1.341 + DOMHighResTimeStamp aEnd)
1.342 +{
1.343 + if (mWidget) {
1.344 + nsContentUtils::AddScriptRunner(new PositionChangeEvent(this));
1.345 + }
1.346 + return NS_OK;
1.347 +}
1.348 +
1.349 +// Helper class, used for text change notification
1.350 +class TextChangeEvent : public nsRunnable
1.351 +{
1.352 +public:
1.353 + TextChangeEvent(IMEContentObserver* aDispatcher,
1.354 + uint32_t aStart, uint32_t aOldEnd, uint32_t aNewEnd,
1.355 + bool aCausedByComposition)
1.356 + : mDispatcher(aDispatcher)
1.357 + , mStart(aStart)
1.358 + , mOldEnd(aOldEnd)
1.359 + , mNewEnd(aNewEnd)
1.360 + , mCausedByComposition(aCausedByComposition)
1.361 + {
1.362 + MOZ_ASSERT(mDispatcher);
1.363 + }
1.364 +
1.365 + NS_IMETHOD Run()
1.366 + {
1.367 + if (mDispatcher->GetWidget()) {
1.368 + IMENotification notification(NOTIFY_IME_OF_TEXT_CHANGE);
1.369 + notification.mTextChangeData.mStartOffset = mStart;
1.370 + notification.mTextChangeData.mOldEndOffset = mOldEnd;
1.371 + notification.mTextChangeData.mNewEndOffset = mNewEnd;
1.372 + notification.mTextChangeData.mCausedByComposition = mCausedByComposition;
1.373 + mDispatcher->GetWidget()->NotifyIME(notification);
1.374 + }
1.375 + return NS_OK;
1.376 + }
1.377 +
1.378 +private:
1.379 + nsRefPtr<IMEContentObserver> mDispatcher;
1.380 + uint32_t mStart, mOldEnd, mNewEnd;
1.381 + bool mCausedByComposition;
1.382 +};
1.383 +
1.384 +void
1.385 +IMEContentObserver::CharacterDataChanged(nsIDocument* aDocument,
1.386 + nsIContent* aContent,
1.387 + CharacterDataChangeInfo* aInfo)
1.388 +{
1.389 + NS_ASSERTION(aContent->IsNodeOfType(nsINode::eTEXT),
1.390 + "character data changed for non-text node");
1.391 +
1.392 + bool causedByComposition = IsEditorHandlingEventForComposition();
1.393 + if (causedByComposition &&
1.394 + !mUpdatePreference.WantChangesCausedByComposition()) {
1.395 + return;
1.396 + }
1.397 +
1.398 + uint32_t offset = 0;
1.399 + // get offsets of change and fire notification
1.400 + nsresult rv =
1.401 + ContentEventHandler::GetFlatTextOffsetOfRange(mRootContent, aContent,
1.402 + aInfo->mChangeStart,
1.403 + &offset,
1.404 + LINE_BREAK_TYPE_NATIVE);
1.405 + NS_ENSURE_SUCCESS_VOID(rv);
1.406 +
1.407 + uint32_t oldEnd = offset + aInfo->mChangeEnd - aInfo->mChangeStart;
1.408 + uint32_t newEnd = offset + aInfo->mReplaceLength;
1.409 +
1.410 + nsContentUtils::AddScriptRunner(
1.411 + new TextChangeEvent(this, offset, oldEnd, newEnd, causedByComposition));
1.412 +}
1.413 +
1.414 +void
1.415 +IMEContentObserver::NotifyContentAdded(nsINode* aContainer,
1.416 + int32_t aStartIndex,
1.417 + int32_t aEndIndex)
1.418 +{
1.419 + bool causedByComposition = IsEditorHandlingEventForComposition();
1.420 + if (causedByComposition &&
1.421 + !mUpdatePreference.WantChangesCausedByComposition()) {
1.422 + return;
1.423 + }
1.424 +
1.425 + uint32_t offset = 0;
1.426 + nsresult rv =
1.427 + ContentEventHandler::GetFlatTextOffsetOfRange(mRootContent, aContainer,
1.428 + aStartIndex, &offset,
1.429 + LINE_BREAK_TYPE_NATIVE);
1.430 + NS_ENSURE_SUCCESS_VOID(rv);
1.431 +
1.432 + // get offset at the end of the last added node
1.433 + nsIContent* childAtStart = aContainer->GetChildAt(aStartIndex);
1.434 + uint32_t addingLength = 0;
1.435 + rv = ContentEventHandler::GetFlatTextOffsetOfRange(childAtStart, aContainer,
1.436 + aEndIndex, &addingLength,
1.437 + LINE_BREAK_TYPE_NATIVE);
1.438 + NS_ENSURE_SUCCESS_VOID(rv);
1.439 +
1.440 + if (!addingLength) {
1.441 + return;
1.442 + }
1.443 +
1.444 + nsContentUtils::AddScriptRunner(
1.445 + new TextChangeEvent(this, offset, offset, offset + addingLength,
1.446 + causedByComposition));
1.447 +}
1.448 +
1.449 +void
1.450 +IMEContentObserver::ContentAppended(nsIDocument* aDocument,
1.451 + nsIContent* aContainer,
1.452 + nsIContent* aFirstNewContent,
1.453 + int32_t aNewIndexInContainer)
1.454 +{
1.455 + NotifyContentAdded(aContainer, aNewIndexInContainer,
1.456 + aContainer->GetChildCount());
1.457 +}
1.458 +
1.459 +void
1.460 +IMEContentObserver::ContentInserted(nsIDocument* aDocument,
1.461 + nsIContent* aContainer,
1.462 + nsIContent* aChild,
1.463 + int32_t aIndexInContainer)
1.464 +{
1.465 + NotifyContentAdded(NODE_FROM(aContainer, aDocument),
1.466 + aIndexInContainer, aIndexInContainer + 1);
1.467 +}
1.468 +
1.469 +void
1.470 +IMEContentObserver::ContentRemoved(nsIDocument* aDocument,
1.471 + nsIContent* aContainer,
1.472 + nsIContent* aChild,
1.473 + int32_t aIndexInContainer,
1.474 + nsIContent* aPreviousSibling)
1.475 +{
1.476 + bool causedByComposition = IsEditorHandlingEventForComposition();
1.477 + if (causedByComposition &&
1.478 + !mUpdatePreference.WantChangesCausedByComposition()) {
1.479 + return;
1.480 + }
1.481 +
1.482 + uint32_t offset = 0;
1.483 + nsresult rv =
1.484 + ContentEventHandler::GetFlatTextOffsetOfRange(mRootContent,
1.485 + NODE_FROM(aContainer,
1.486 + aDocument),
1.487 + aIndexInContainer, &offset,
1.488 + LINE_BREAK_TYPE_NATIVE);
1.489 + NS_ENSURE_SUCCESS_VOID(rv);
1.490 +
1.491 + // get offset at the end of the deleted node
1.492 + int32_t nodeLength =
1.493 + aChild->IsNodeOfType(nsINode::eTEXT) ?
1.494 + static_cast<int32_t>(aChild->TextLength()) :
1.495 + std::max(static_cast<int32_t>(aChild->GetChildCount()), 1);
1.496 + MOZ_ASSERT(nodeLength >= 0, "The node length is out of range");
1.497 + uint32_t textLength = 0;
1.498 + rv = ContentEventHandler::GetFlatTextOffsetOfRange(aChild, aChild,
1.499 + nodeLength, &textLength,
1.500 + LINE_BREAK_TYPE_NATIVE);
1.501 + NS_ENSURE_SUCCESS_VOID(rv);
1.502 +
1.503 + if (!textLength) {
1.504 + return;
1.505 + }
1.506 +
1.507 + nsContentUtils::AddScriptRunner(
1.508 + new TextChangeEvent(this, offset, offset + textLength, offset,
1.509 + causedByComposition));
1.510 +}
1.511 +
1.512 +static nsIContent*
1.513 +GetContentBR(dom::Element* aElement)
1.514 +{
1.515 + if (!aElement->IsNodeOfType(nsINode::eCONTENT)) {
1.516 + return nullptr;
1.517 + }
1.518 + nsIContent* content = static_cast<nsIContent*>(aElement);
1.519 + return content->IsHTML(nsGkAtoms::br) ? content : nullptr;
1.520 +}
1.521 +
1.522 +void
1.523 +IMEContentObserver::AttributeWillChange(nsIDocument* aDocument,
1.524 + dom::Element* aElement,
1.525 + int32_t aNameSpaceID,
1.526 + nsIAtom* aAttribute,
1.527 + int32_t aModType)
1.528 +{
1.529 + nsIContent *content = GetContentBR(aElement);
1.530 + mPreAttrChangeLength = content ?
1.531 + ContentEventHandler::GetNativeTextLength(content) : 0;
1.532 +}
1.533 +
1.534 +void
1.535 +IMEContentObserver::AttributeChanged(nsIDocument* aDocument,
1.536 + dom::Element* aElement,
1.537 + int32_t aNameSpaceID,
1.538 + nsIAtom* aAttribute,
1.539 + int32_t aModType)
1.540 +{
1.541 + bool causedByComposition = IsEditorHandlingEventForComposition();
1.542 + if (causedByComposition &&
1.543 + !mUpdatePreference.WantChangesCausedByComposition()) {
1.544 + return;
1.545 + }
1.546 +
1.547 + nsIContent *content = GetContentBR(aElement);
1.548 + if (!content) {
1.549 + return;
1.550 + }
1.551 +
1.552 + uint32_t postAttrChangeLength =
1.553 + ContentEventHandler::GetNativeTextLength(content);
1.554 + if (postAttrChangeLength == mPreAttrChangeLength) {
1.555 + return;
1.556 + }
1.557 + uint32_t start;
1.558 + nsresult rv =
1.559 + ContentEventHandler::GetFlatTextOffsetOfRange(mRootContent, content,
1.560 + 0, &start,
1.561 + LINE_BREAK_TYPE_NATIVE);
1.562 + NS_ENSURE_SUCCESS_VOID(rv);
1.563 +
1.564 + nsContentUtils::AddScriptRunner(
1.565 + new TextChangeEvent(this, start, start + mPreAttrChangeLength,
1.566 + start + postAttrChangeLength, causedByComposition));
1.567 +}
1.568 +
1.569 +} // namespace mozilla
