gecko-dev/accessible/android/AccessibleWrap.cpp

702 строки
22 KiB
C++

/* -*- 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/. */
#include "AccessibleWrap.h"
#include "Accessible-inl.h"
#include "AndroidInputType.h"
#include "DocAccessibleWrap.h"
#include "IDSet.h"
#include "JavaBuiltins.h"
#include "SessionAccessibility.h"
#include "nsAccessibilityService.h"
#include "nsPersistentProperties.h"
#include "nsIAccessibleAnnouncementEvent.h"
#include "nsIStringBundle.h"
#include "nsAccUtils.h"
#include "nsTextEquivUtils.h"
#include "mozilla/a11y/PDocAccessibleChild.h"
#include "mozilla/jni/GeckoBundleUtils.h"
#define ROLE_STRINGS_URL "chrome://global/locale/AccessFu.properties"
using namespace mozilla::a11y;
// IDs should be a positive 32bit integer.
IDSet sIDSet(31UL);
//-----------------------------------------------------
// construction
//-----------------------------------------------------
AccessibleWrap::AccessibleWrap(nsIContent* aContent, DocAccessible* aDoc)
: Accessible(aContent, aDoc) {
if (aDoc) {
mID = AcquireID();
DocAccessibleWrap* doc = static_cast<DocAccessibleWrap*>(aDoc);
doc->AddID(mID, this);
}
}
//-----------------------------------------------------
// destruction
//-----------------------------------------------------
AccessibleWrap::~AccessibleWrap() {}
nsresult AccessibleWrap::HandleAccEvent(AccEvent* aEvent) {
auto accessible = static_cast<AccessibleWrap*>(aEvent->GetAccessible());
NS_ENSURE_TRUE(accessible, NS_ERROR_FAILURE);
DocAccessibleWrap* doc =
static_cast<DocAccessibleWrap*>(accessible->Document());
if (doc) {
switch (aEvent->GetEventType()) {
case nsIAccessibleEvent::EVENT_FOCUS: {
if (DocAccessibleWrap* topContentDoc =
doc->GetTopLevelContentDoc(accessible)) {
topContentDoc->CacheFocusPath(accessible);
}
break;
}
case nsIAccessibleEvent::EVENT_VIRTUALCURSOR_CHANGED: {
AccVCChangeEvent* vcEvent = downcast_accEvent(aEvent);
auto newPosition =
static_cast<AccessibleWrap*>(vcEvent->NewAccessible());
if (newPosition) {
if (DocAccessibleWrap* topContentDoc =
doc->GetTopLevelContentDoc(accessible)) {
topContentDoc->CacheFocusPath(newPosition);
}
}
break;
}
case nsIAccessibleEvent::EVENT_SHOW:
case nsIAccessibleEvent::EVENT_HIDE: {
if (DocAccessibleWrap* topContentDoc =
doc->GetTopLevelContentDoc(accessible)) {
topContentDoc->CacheViewport();
}
break;
}
default:
break;
}
}
nsresult rv = Accessible::HandleAccEvent(aEvent);
NS_ENSURE_SUCCESS(rv, rv);
accessible->HandleLiveRegionEvent(aEvent);
if (IPCAccessibilityActive()) {
return NS_OK;
}
// The accessible can become defunct if we have an xpcom event listener
// which decides it would be fun to change the DOM and flush layout.
if (accessible->IsDefunct() || !accessible->IsBoundToParent()) {
return NS_OK;
}
if (doc) {
if (!nsCoreUtils::IsContentDocument(doc->DocumentNode())) {
return NS_OK;
}
}
RefPtr<SessionAccessibility> sessionAcc =
SessionAccessibility::GetInstanceFor(accessible);
if (!sessionAcc) {
return NS_OK;
}
switch (aEvent->GetEventType()) {
case nsIAccessibleEvent::EVENT_FOCUS:
sessionAcc->SendFocusEvent(accessible);
break;
case nsIAccessibleEvent::EVENT_VIRTUALCURSOR_CHANGED: {
AccVCChangeEvent* vcEvent = downcast_accEvent(aEvent);
RefPtr<AccessibleWrap> newPosition =
static_cast<AccessibleWrap*>(vcEvent->NewAccessible());
auto oldPosition = static_cast<AccessibleWrap*>(vcEvent->OldAccessible());
if (sessionAcc && newPosition) {
if (oldPosition != newPosition) {
if (vcEvent->Reason() == nsIAccessiblePivot::REASON_POINT) {
sessionAcc->SendHoverEnterEvent(newPosition);
} else {
sessionAcc->SendAccessibilityFocusedEvent(newPosition);
}
}
if (vcEvent->BoundaryType() != nsIAccessiblePivot::NO_BOUNDARY) {
sessionAcc->SendTextTraversedEvent(
newPosition, vcEvent->NewStartOffset(), vcEvent->NewEndOffset());
}
}
break;
}
case nsIAccessibleEvent::EVENT_TEXT_CARET_MOVED: {
AccCaretMoveEvent* event = downcast_accEvent(aEvent);
sessionAcc->SendTextSelectionChangedEvent(accessible,
event->GetCaretOffset());
break;
}
case nsIAccessibleEvent::EVENT_TEXT_INSERTED:
case nsIAccessibleEvent::EVENT_TEXT_REMOVED: {
AccTextChangeEvent* event = downcast_accEvent(aEvent);
sessionAcc->SendTextChangedEvent(
accessible, event->ModifiedText(), event->GetStartOffset(),
event->GetLength(), event->IsTextInserted(),
event->IsFromUserInput());
break;
}
case nsIAccessibleEvent::EVENT_STATE_CHANGE: {
AccStateChangeEvent* event = downcast_accEvent(aEvent);
auto state = event->GetState();
if (state & states::CHECKED) {
sessionAcc->SendClickedEvent(accessible, event->IsStateEnabled());
}
if (state & states::SELECTED) {
sessionAcc->SendSelectedEvent(accessible, event->IsStateEnabled());
}
if (state & states::BUSY) {
sessionAcc->SendWindowStateChangedEvent(accessible);
}
break;
}
case nsIAccessibleEvent::EVENT_SCROLLING: {
AccScrollingEvent* event = downcast_accEvent(aEvent);
sessionAcc->SendScrollingEvent(accessible, event->ScrollX(),
event->ScrollY(), event->MaxScrollX(),
event->MaxScrollY());
break;
}
case nsIAccessibleEvent::EVENT_ANNOUNCEMENT: {
AccAnnouncementEvent* event = downcast_accEvent(aEvent);
sessionAcc->SendAnnouncementEvent(accessible, event->Announcement(),
event->Priority());
break;
}
default:
break;
}
return NS_OK;
}
void AccessibleWrap::Shutdown() {
if (mDoc) {
if (mID > 0) {
if (auto doc = static_cast<DocAccessibleWrap*>(mDoc.get())) {
doc->RemoveID(mID);
}
ReleaseID(mID);
mID = 0;
}
}
Accessible::Shutdown();
}
bool AccessibleWrap::DoAction(uint8_t aIndex) const {
if (ActionCount()) {
return Accessible::DoAction(aIndex);
}
if (mContent) {
// We still simulate a click on an accessible even if there is no
// known actions. For the sake of bad markup.
DoCommand();
return true;
}
return false;
}
int32_t AccessibleWrap::AcquireID() { return sIDSet.GetID(); }
void AccessibleWrap::ReleaseID(int32_t aID) { sIDSet.ReleaseID(aID); }
void AccessibleWrap::SetTextContents(const nsAString& aText) {
if (IsHyperText()) {
AsHyperText()->ReplaceText(aText);
}
}
void AccessibleWrap::GetTextContents(nsAString& aText) {
// For now it is a simple wrapper for getting entire range of TextSubstring.
// In the future this may be smarter and retrieve a flattened string.
if (IsHyperText()) {
AsHyperText()->TextSubstring(0, -1, aText);
}
}
bool AccessibleWrap::GetSelectionBounds(int32_t* aStartOffset,
int32_t* aEndOffset) {
if (IsHyperText()) {
return AsHyperText()->SelectionBoundsAt(0, aStartOffset, aEndOffset);
}
return false;
}
uint32_t AccessibleWrap::GetFlags(role aRole, uint64_t aState,
uint8_t aActionCount) {
uint32_t flags = 0;
if (aState & states::CHECKABLE) {
flags |= java::SessionAccessibility::FLAG_CHECKABLE;
}
if (aState & states::CHECKED) {
flags |= java::SessionAccessibility::FLAG_CHECKED;
}
if (aState & states::INVALID) {
flags |= java::SessionAccessibility::FLAG_CONTENT_INVALID;
}
if (aState & states::EDITABLE) {
flags |= java::SessionAccessibility::FLAG_EDITABLE;
}
if (aActionCount && aRole != roles::TEXT_LEAF) {
flags |= java::SessionAccessibility::FLAG_CLICKABLE;
}
if (aState & states::ENABLED) {
flags |= java::SessionAccessibility::FLAG_ENABLED;
}
if (aState & states::FOCUSABLE) {
flags |= java::SessionAccessibility::FLAG_FOCUSABLE;
}
if (aState & states::FOCUSED) {
flags |= java::SessionAccessibility::FLAG_FOCUSED;
}
if (aState & states::MULTI_LINE) {
flags |= java::SessionAccessibility::FLAG_MULTI_LINE;
}
if (aState & states::SELECTABLE) {
flags |= java::SessionAccessibility::FLAG_SELECTABLE;
}
if (aState & states::SELECTED) {
flags |= java::SessionAccessibility::FLAG_SELECTED;
}
if ((aState & (states::INVISIBLE | states::OFFSCREEN)) == 0) {
flags |= java::SessionAccessibility::FLAG_VISIBLE_TO_USER;
}
if (aRole == roles::PASSWORD_TEXT) {
flags |= java::SessionAccessibility::FLAG_PASSWORD;
}
return flags;
}
void AccessibleWrap::GetRoleDescription(role aRole,
nsIPersistentProperties* aAttributes,
nsAString& aGeckoRole,
nsAString& aRoleDescription) {
nsresult rv = NS_OK;
nsCOMPtr<nsIStringBundleService> sbs =
do_GetService(NS_STRINGBUNDLE_CONTRACTID, &rv);
if (NS_FAILED(rv)) {
NS_WARNING("Failed to get string bundle service");
return;
}
nsCOMPtr<nsIStringBundle> bundle;
rv = sbs->CreateBundle(ROLE_STRINGS_URL, getter_AddRefs(bundle));
if (NS_FAILED(rv)) {
NS_WARNING("Failed to get string bundle");
return;
}
if (aRole == roles::HEADING && aAttributes) {
// The heading level is an attribute, so we need that.
nsString level;
rv = aAttributes->GetStringProperty(NS_LITERAL_CSTRING("level"), level);
if (NS_SUCCEEDED(rv)) {
const char16_t* formatString[] = {level.get()};
rv = bundle->FormatStringFromName("headingLevel", formatString, 1,
aRoleDescription);
if (NS_SUCCEEDED(rv)) {
return;
}
}
}
GetAccService()->GetStringRole(aRole, aGeckoRole);
rv = bundle->GetStringFromName(NS_ConvertUTF16toUTF8(aGeckoRole).get(),
aRoleDescription);
if (NS_FAILED(rv)) {
aRoleDescription.AssignLiteral("");
}
}
already_AddRefed<nsIPersistentProperties>
AccessibleWrap::AttributeArrayToProperties(
const nsTArray<Attribute>& aAttributes) {
RefPtr<nsPersistentProperties> props = new nsPersistentProperties();
nsAutoString unused;
for (size_t i = 0; i < aAttributes.Length(); i++) {
props->SetStringProperty(aAttributes.ElementAt(i).Name(),
aAttributes.ElementAt(i).Value(), unused);
}
return props.forget();
}
int32_t AccessibleWrap::GetAndroidClass(role aRole) {
#define ROLE(geckoRole, stringRole, atkRole, macRole, msaaRole, ia2Role, \
androidClass, nameRule) \
case roles::geckoRole: \
return androidClass;
switch (aRole) {
#include "RoleMap.h"
default:
return java::SessionAccessibility::CLASSNAME_VIEW;
}
#undef ROLE
}
int32_t AccessibleWrap::GetInputType(const nsString& aInputTypeAttr) {
if (aInputTypeAttr.EqualsIgnoreCase("email")) {
return java::sdk::InputType::TYPE_CLASS_TEXT |
java::sdk::InputType::TYPE_TEXT_VARIATION_WEB_EMAIL_ADDRESS;
}
if (aInputTypeAttr.EqualsIgnoreCase("number")) {
return java::sdk::InputType::TYPE_CLASS_NUMBER;
}
if (aInputTypeAttr.EqualsIgnoreCase("password")) {
return java::sdk::InputType::TYPE_CLASS_TEXT |
java::sdk::InputType::TYPE_TEXT_VARIATION_WEB_PASSWORD;
}
if (aInputTypeAttr.EqualsIgnoreCase("tel")) {
return java::sdk::InputType::TYPE_CLASS_PHONE;
}
if (aInputTypeAttr.EqualsIgnoreCase("text")) {
return java::sdk::InputType::TYPE_CLASS_TEXT |
java::sdk::InputType::TYPE_TEXT_VARIATION_WEB_EDIT_TEXT;
}
if (aInputTypeAttr.EqualsIgnoreCase("url")) {
return java::sdk::InputType::TYPE_CLASS_TEXT |
java::sdk::InputType::TYPE_TEXT_VARIATION_URI;
}
return 0;
}
void AccessibleWrap::WrapperDOMNodeID(nsString& aDOMNodeID) {
if (mContent) {
nsAtom* id = mContent->GetID();
if (id) {
id->ToString(aDOMNodeID);
}
}
}
bool AccessibleWrap::WrapperRangeInfo(double* aCurVal, double* aMinVal,
double* aMaxVal, double* aStep) {
if (HasNumericValue()) {
*aCurVal = CurValue();
*aMinVal = MinValue();
*aMaxVal = MaxValue();
*aStep = Step();
return true;
}
return false;
}
mozilla::java::GeckoBundle::LocalRef AccessibleWrap::ToBundle(bool aSmall) {
nsAutoString name;
Name(name);
nsAutoString textValue;
Value(textValue);
nsAutoString nodeID;
WrapperDOMNodeID(nodeID);
nsAutoString description;
Description(description);
if (aSmall) {
return ToBundle(State(), Bounds(), ActionCount(), name, textValue, nodeID,
description);
}
double curValue = UnspecifiedNaN<double>();
double minValue = UnspecifiedNaN<double>();
double maxValue = UnspecifiedNaN<double>();
double step = UnspecifiedNaN<double>();
WrapperRangeInfo(&curValue, &minValue, &maxValue, &step);
nsCOMPtr<nsIPersistentProperties> attributes = Attributes();
return ToBundle(State(), Bounds(), ActionCount(), name, textValue, nodeID,
description, curValue, minValue, maxValue, step, attributes);
}
mozilla::java::GeckoBundle::LocalRef AccessibleWrap::ToBundle(
const uint64_t aState, const nsIntRect& aBounds, const uint8_t aActionCount,
const nsString& aName, const nsString& aTextValue,
const nsString& aDOMNodeID, const nsString& aDescription,
const double& aCurVal, const double& aMinVal, const double& aMaxVal,
const double& aStep, nsIPersistentProperties* aAttributes) {
if (!IsProxy() && IsDefunct()) {
return nullptr;
}
GECKOBUNDLE_START(nodeInfo);
GECKOBUNDLE_PUT(nodeInfo, "id", java::sdk::Integer::ValueOf(VirtualViewID()));
AccessibleWrap* parent = WrapperParent();
GECKOBUNDLE_PUT(
nodeInfo, "parentId",
java::sdk::Integer::ValueOf(parent ? parent->VirtualViewID() : 0));
role role = WrapperRole();
uint32_t flags = GetFlags(role, aState, aActionCount);
GECKOBUNDLE_PUT(nodeInfo, "flags", java::sdk::Integer::ValueOf(flags));
GECKOBUNDLE_PUT(nodeInfo, "className",
java::sdk::Integer::ValueOf(AndroidClass()));
if (aState & states::EDITABLE) {
nsAutoString hint(aName);
if (!aDescription.IsEmpty()) {
hint.AppendLiteral(" ");
hint.Append(aDescription);
}
GECKOBUNDLE_PUT(nodeInfo, "hint", jni::StringParam(hint));
GECKOBUNDLE_PUT(nodeInfo, "text", jni::StringParam(aTextValue));
} else {
GECKOBUNDLE_PUT(nodeInfo, "text", jni::StringParam(aName));
if (!aDescription.IsEmpty()) {
GECKOBUNDLE_PUT(nodeInfo, "hint", jni::StringParam(aDescription));
}
}
nsAutoString geckoRole;
nsAutoString roleDescription;
if (VirtualViewID() != kNoID) {
GetRoleDescription(role, aAttributes, geckoRole, roleDescription);
}
GECKOBUNDLE_PUT(nodeInfo, "roleDescription",
jni::StringParam(roleDescription));
GECKOBUNDLE_PUT(nodeInfo, "geckoRole", jni::StringParam(geckoRole));
GECKOBUNDLE_PUT(nodeInfo, "roleDescription",
jni::StringParam(roleDescription));
GECKOBUNDLE_PUT(nodeInfo, "geckoRole", jni::StringParam(geckoRole));
if (!aDOMNodeID.IsEmpty()) {
GECKOBUNDLE_PUT(nodeInfo, "viewIdResourceName",
jni::StringParam(aDOMNodeID));
}
nsIntRect bounds = Bounds();
const int32_t data[4] = {bounds.x, bounds.y, bounds.x + bounds.width,
bounds.y + bounds.height};
GECKOBUNDLE_PUT(nodeInfo, "bounds", jni::IntArray::New(data, 4));
if (HasNumericValue()) {
GECKOBUNDLE_START(rangeInfo);
if (aMaxVal == 1 && aMinVal == 0) {
GECKOBUNDLE_PUT(rangeInfo, "type",
java::sdk::Integer::ValueOf(2)); // percent
} else if (std::round(aStep) != aStep) {
GECKOBUNDLE_PUT(rangeInfo, "type",
java::sdk::Integer::ValueOf(1)); // float
} else {
GECKOBUNDLE_PUT(rangeInfo, "type",
java::sdk::Integer::ValueOf(0)); // integer
}
if (!IsNaN(aCurVal)) {
GECKOBUNDLE_PUT(rangeInfo, "current", java::sdk::Double::New(aCurVal));
}
if (!IsNaN(aMinVal)) {
GECKOBUNDLE_PUT(rangeInfo, "min", java::sdk::Double::New(aMinVal));
}
if (!IsNaN(aMaxVal)) {
GECKOBUNDLE_PUT(rangeInfo, "max", java::sdk::Double::New(aMaxVal));
}
GECKOBUNDLE_FINISH(rangeInfo);
GECKOBUNDLE_PUT(nodeInfo, "rangeInfo", rangeInfo);
}
if (aAttributes) {
nsString inputTypeAttr;
nsAccUtils::GetAccAttr(aAttributes, nsGkAtoms::textInputType,
inputTypeAttr);
int32_t inputType = GetInputType(inputTypeAttr);
if (inputType) {
GECKOBUNDLE_PUT(nodeInfo, "inputType",
java::sdk::Integer::ValueOf(inputType));
}
nsString posinset;
nsresult rv = aAttributes->GetStringProperty(NS_LITERAL_CSTRING("posinset"),
posinset);
if (NS_SUCCEEDED(rv)) {
int32_t rowIndex;
if (sscanf(NS_ConvertUTF16toUTF8(posinset).get(), "%d", &rowIndex) > 0) {
GECKOBUNDLE_START(collectionItemInfo);
GECKOBUNDLE_PUT(collectionItemInfo, "rowIndex",
java::sdk::Integer::ValueOf(rowIndex));
GECKOBUNDLE_PUT(collectionItemInfo, "columnIndex",
java::sdk::Integer::ValueOf(0));
GECKOBUNDLE_PUT(collectionItemInfo, "rowSpan",
java::sdk::Integer::ValueOf(1));
GECKOBUNDLE_PUT(collectionItemInfo, "columnSpan",
java::sdk::Integer::ValueOf(1));
GECKOBUNDLE_FINISH(collectionItemInfo);
GECKOBUNDLE_PUT(nodeInfo, "collectionItemInfo", collectionItemInfo);
}
}
nsString colSize;
rv = aAttributes->GetStringProperty(NS_LITERAL_CSTRING("child-item-count"),
colSize);
if (NS_SUCCEEDED(rv)) {
int32_t rowCount;
if (sscanf(NS_ConvertUTF16toUTF8(colSize).get(), "%d", &rowCount) > 0) {
GECKOBUNDLE_START(collectionInfo);
GECKOBUNDLE_PUT(collectionInfo, "rowCount",
java::sdk::Integer::ValueOf(rowCount));
GECKOBUNDLE_PUT(collectionInfo, "columnCount",
java::sdk::Integer::ValueOf(1));
nsString unused;
rv = aAttributes->GetStringProperty(NS_LITERAL_CSTRING("hierarchical"),
unused);
if (NS_SUCCEEDED(rv)) {
GECKOBUNDLE_PUT(collectionInfo, "isHierarchical",
java::sdk::Boolean::TRUE());
}
if (IsSelect()) {
int32_t selectionMode = (aState & states::MULTISELECTABLE) ? 2 : 1;
GECKOBUNDLE_PUT(collectionInfo, "selectionMode",
java::sdk::Integer::ValueOf(selectionMode));
}
GECKOBUNDLE_FINISH(collectionInfo);
GECKOBUNDLE_PUT(nodeInfo, "collectionInfo", collectionInfo);
}
}
}
bool mustPrune =
IsProxy() ? nsAccUtils::MustPrune(Proxy()) : nsAccUtils::MustPrune(this);
if (!mustPrune) {
auto childCount = ChildCount();
nsTArray<int32_t> children(childCount);
for (uint32_t i = 0; i < childCount; i++) {
auto child = static_cast<AccessibleWrap*>(GetChildAt(i));
children.AppendElement(child->VirtualViewID());
}
GECKOBUNDLE_PUT(nodeInfo, "children",
jni::IntArray::New(children.Elements(), children.Length()));
}
GECKOBUNDLE_FINISH(nodeInfo);
return nodeInfo;
}
void AccessibleWrap::GetTextEquiv(nsString& aText) {
if (nsTextEquivUtils::HasNameRule(this, eNameFromSubtreeIfReqRule)) {
// This is an accessible that normally doesn't get its name from its
// subtree, so we collect the text equivalent explicitly.
nsTextEquivUtils::GetTextEquivFromSubtree(this, aText);
} else {
Name(aText);
}
}
bool AccessibleWrap::HandleLiveRegionEvent(AccEvent* aEvent) {
auto eventType = aEvent->GetEventType();
if (eventType != nsIAccessibleEvent::EVENT_TEXT_INSERTED &&
eventType != nsIAccessibleEvent::EVENT_NAME_CHANGE) {
// XXX: Right now only announce text inserted events. aria-relevant=removals
// is potentially on the chopping block[1]. We also don't support editable
// text because we currently can't descern the source of the change[2].
// 1. https://github.com/w3c/aria/issues/712
// 2. https://bugzilla.mozilla.org/show_bug.cgi?id=1531189
return false;
}
if (aEvent->IsFromUserInput()) {
return false;
}
nsCOMPtr<nsIPersistentProperties> attributes = Attributes();
nsString live;
nsresult rv =
attributes->GetStringProperty(NS_LITERAL_CSTRING("container-live"), live);
if (!NS_SUCCEEDED(rv)) {
return false;
}
uint16_t priority = live.EqualsIgnoreCase("assertive")
? nsIAccessibleAnnouncementEvent::ASSERTIVE
: nsIAccessibleAnnouncementEvent::POLITE;
nsString atomic;
rv = attributes->GetStringProperty(NS_LITERAL_CSTRING("container-atomic"),
atomic);
Accessible* announcementTarget = this;
nsAutoString announcement;
if (atomic.EqualsIgnoreCase("true")) {
Accessible* atomicAncestor = nullptr;
for (Accessible* parent = announcementTarget; parent;
parent = parent->Parent()) {
Element* element = parent->Elm();
if (element &&
element->AttrValueIs(kNameSpaceID_None, nsGkAtoms::aria_atomic,
nsGkAtoms::_true, eCaseMatters)) {
atomicAncestor = parent;
break;
}
}
if (atomicAncestor) {
announcementTarget = atomicAncestor;
static_cast<AccessibleWrap*>(atomicAncestor)->GetTextEquiv(announcement);
}
} else {
GetTextEquiv(announcement);
}
announcement.CompressWhitespace();
if (announcement.IsEmpty()) {
return false;
}
announcementTarget->Announce(announcement, priority);
return true;
}