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/* 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
#include "FocusManager.h"
#include "LocalAccessible-inl.h"
#include "DocAccessible-inl.h"
#include "nsAccessibilityService.h"
#include "nsEventShell.h"
#include "nsFocusManager.h"
#include "mozilla/a11y/DocAccessibleParent.h"
#include "mozilla/EventStateManager.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/BrowsingContext.h"
#include "mozilla/dom/BrowserParent.h"
namespace mozilla {
namespace a11y {
FocusManager::FocusManager() {}
FocusManager::~FocusManager() {}
LocalAccessible* FocusManager::FocusedLocalAccessible() const {
MOZ_ASSERT(NS_IsMainThread());
if (mActiveItem) {
if (mActiveItem->IsDefunct()) {
MOZ_ASSERT_UNREACHABLE("Stored active item is unbound from document");
return nullptr;
}
return mActiveItem;
}
if (nsAccessibilityService::IsShutdown()) {
// We might try to get or create a DocAccessible below, which isn't safe (or
// useful) if the accessibility service is shutting down.
return nullptr;
}
nsINode* focusedNode = FocusedDOMNode();
if (focusedNode) {
DocAccessible* doc =
GetAccService()->GetDocAccessible(focusedNode->OwnerDoc());
return doc ? doc->GetAccessibleEvenIfNotInMapOrContainer(focusedNode)
: nullptr;
}
return nullptr;
}
Accessible* FocusManager::FocusedAccessible() const {
#if defined(ANDROID)
// It's not safe to call FocusedLocalAccessible() except on the main thread.
// Android might query RemoteAccessibles on the UI thread, which might call
// FocusedAccessible(). Never try to get the focused LocalAccessible in this
// case.
if (NS_IsMainThread()) {
if (Accessible* focusedAcc = FocusedLocalAccessible()) {
return focusedAcc;
}
} else {
nsAccessibilityService::GetAndroidMonitor().AssertCurrentThreadOwns();
}
return mFocusedRemoteDoc ? mFocusedRemoteDoc->GetFocusedAcc() : nullptr;
#else
if (Accessible* focusedAcc = FocusedLocalAccessible()) {
return focusedAcc;
}
if (!XRE_IsParentProcess()) {
// DocAccessibleParent's don't exist in the content
// process, so we can't return anything useful if this
// is the case.
return nullptr;
}
nsFocusManager* focusManagerDOM = nsFocusManager::GetFocusManager();
if (!focusManagerDOM) {
return nullptr;
}
// If we call GetFocusedBrowsingContext from the chrome process
// it returns the BrowsingContext for the focused _window_, which
// is not helpful here. Instead use GetFocusedBrowsingContextInChrome
// which returns the content BrowsingContext that has focus.
dom::BrowsingContext* focusedContext =
focusManagerDOM->GetFocusedBrowsingContextInChrome();
DocAccessibleParent* focusedDoc =
DocAccessibleParent::GetFrom(focusedContext);
return focusedDoc ? focusedDoc->GetFocusedAcc() : nullptr;
#endif // defined(ANDROID)
}
bool FocusManager::IsFocusWithin(const Accessible* aContainer) const {
Accessible* child = FocusedAccessible();
while (child) {
if (child == aContainer) return true;
child = child->Parent();
}
return false;
}
FocusManager::FocusDisposition FocusManager::IsInOrContainsFocus(
const LocalAccessible* aAccessible) const {
LocalAccessible* focus = FocusedLocalAccessible();
if (!focus) return eNone;
// If focused.
if (focus == aAccessible) return eFocused;
// If contains the focus.
LocalAccessible* child = focus->LocalParent();
while (child) {
if (child == aAccessible) return eContainsFocus;
child = child->LocalParent();
}
// If contained by focus.
child = aAccessible->LocalParent();
while (child) {
if (child == focus) return eContainedByFocus;
child = child->LocalParent();
}
return eNone;
}
bool FocusManager::WasLastFocused(const LocalAccessible* aAccessible) const {
return mLastFocus == aAccessible;
}
void FocusManager::NotifyOfDOMFocus(nsISupports* aTarget) {
#ifdef A11Y_LOG
if (logging::IsEnabled(logging::eFocus)) {
logging::FocusNotificationTarget("DOM focus", "Target", aTarget);
}
#endif
mActiveItem = nullptr;
nsCOMPtr<nsINode> targetNode(do_QueryInterface(aTarget));
if (targetNode) {
DocAccessible* document =
GetAccService()->GetDocAccessible(targetNode->OwnerDoc());
if (document) {
// Set selection listener for focused element.
if (targetNode->IsElement()) {
SelectionMgr()->SetControlSelectionListener(targetNode->AsElement());
}
document->HandleNotification<FocusManager, nsINode>(
this, &FocusManager::ProcessDOMFocus, targetNode);
}
}
}
void FocusManager::NotifyOfDOMBlur(nsISupports* aTarget) {
#ifdef A11Y_LOG
if (logging::IsEnabled(logging::eFocus)) {
logging::FocusNotificationTarget("DOM blur", "Target", aTarget);
}
#endif
mActiveItem = nullptr;
// If DOM document stays focused then fire accessible focus event to process
// the case when no element within this DOM document will be focused.
nsCOMPtr<nsINode> targetNode(do_QueryInterface(aTarget));
if (targetNode && targetNode->OwnerDoc() == FocusedDOMDocument()) {
dom::Document* DOMDoc = targetNode->OwnerDoc();
DocAccessible* document = GetAccService()->GetDocAccessible(DOMDoc);
if (document) {
// Clear selection listener for previously focused element.
if (targetNode->IsElement()) {
SelectionMgr()->ClearControlSelectionListener();
}
document->HandleNotification<FocusManager, nsINode>(
this, &FocusManager::ProcessDOMFocus, DOMDoc);
}
}
}
void FocusManager::ActiveItemChanged(LocalAccessible* aItem,
bool aCheckIfActive) {
#ifdef A11Y_LOG
if (logging::IsEnabled(logging::eFocus)) {
logging::FocusNotificationTarget("active item changed", "Item", aItem);
}
#endif
// Nothing changed, happens for XUL trees and HTML selects.
if (aItem && aItem == mActiveItem) {
return;
}
mActiveItem = nullptr;
if (aItem && aCheckIfActive) {
LocalAccessible* widget = aItem->ContainerWidget();
#ifdef A11Y_LOG
if (logging::IsEnabled(logging::eFocus)) logging::ActiveWidget(widget);
#endif
if (!widget || !widget->IsActiveWidget() || !widget->AreItemsOperable()) {
return;
}
}
mActiveItem = aItem;
// If mActiveItem is null we may need to shift a11y focus back to a remote
// document. For example, when combobox popup is closed, then
// the focus should be moved back to the combobox.
if (!mActiveItem && XRE_IsParentProcess()) {
dom::BrowserParent* browser = dom::BrowserParent::GetFocused();
if (browser) {
a11y::DocAccessibleParent* dap = browser->GetTopLevelDocAccessible();
if (dap) {
Unused << dap->SendRestoreFocus();
}
}
}
// If active item is changed then fire accessible focus event on it, otherwise
// if there's no an active item then fire focus event to accessible having
// DOM focus.
LocalAccessible* target = FocusedLocalAccessible();
if (target) {
DispatchFocusEvent(target->Document(), target);
}
}
void FocusManager::ForceFocusEvent() {
nsINode* focusedNode = FocusedDOMNode();
if (focusedNode) {
DocAccessible* document =
GetAccService()->GetDocAccessible(focusedNode->OwnerDoc());
if (document) {
document->HandleNotification<FocusManager, nsINode>(
this, &FocusManager::ProcessDOMFocus, focusedNode);
}
}
}
void FocusManager::DispatchFocusEvent(DocAccessible* aDocument,
LocalAccessible* aTarget) {
MOZ_ASSERT(aDocument, "No document for focused accessible!");
if (aDocument) {
RefPtr<AccEvent> event =
new AccEvent(nsIAccessibleEvent::EVENT_FOCUS, aTarget, eAutoDetect,
AccEvent::eCoalesceOfSameType);
aDocument->FireDelayedEvent(event);
mLastFocus = aTarget;
if (mActiveItem != aTarget) {
// This new focus overrides the stored active item, so clear the active
// item. Among other things, the old active item might die.
mActiveItem = nullptr;
}
#ifdef A11Y_LOG
if (logging::IsEnabled(logging::eFocus)) logging::FocusDispatched(aTarget);
#endif
}
}
void FocusManager::ProcessDOMFocus(nsINode* aTarget) {
#ifdef A11Y_LOG
if (logging::IsEnabled(logging::eFocus)) {
logging::FocusNotificationTarget("process DOM focus", "Target", aTarget);
}
#endif
DocAccessible* document =
GetAccService()->GetDocAccessible(aTarget->OwnerDoc());
if (!document) return;
LocalAccessible* target =
document->GetAccessibleEvenIfNotInMapOrContainer(aTarget);
if (target) {
// Check if still focused. Otherwise we can end up with storing the active
// item for control that isn't focused anymore.
nsINode* focusedNode = FocusedDOMNode();
if (!focusedNode) return;
LocalAccessible* DOMFocus =
document->GetAccessibleEvenIfNotInMapOrContainer(focusedNode);
if (target != DOMFocus) return;
LocalAccessible* activeItem = target->CurrentItem();
if (activeItem) {
mActiveItem = activeItem;
target = activeItem;
}
DispatchFocusEvent(document, target);
}
}
void FocusManager::ProcessFocusEvent(AccEvent* aEvent) {
MOZ_ASSERT(aEvent->GetEventType() == nsIAccessibleEvent::EVENT_FOCUS,
"Focus event is expected!");
// Emit focus event if event target is the active item. Otherwise then check
// if it's still focused and then update active item and emit focus event.
LocalAccessible* target = aEvent->GetAccessible();
MOZ_ASSERT(!target->IsDefunct());
if (target != mActiveItem) {
// Check if still focused. Otherwise we can end up with storing the active
// item for control that isn't focused anymore.
DocAccessible* document = aEvent->Document();
nsINode* focusedNode = FocusedDOMNode();
if (!focusedNode) return;
LocalAccessible* DOMFocus =
document->GetAccessibleEvenIfNotInMapOrContainer(focusedNode);
if (target != DOMFocus) return;
LocalAccessible* activeItem = target->CurrentItem();
if (activeItem) {
mActiveItem = activeItem;
target = activeItem;
MOZ_ASSERT(!target->IsDefunct());
}
}
// Fire menu start/end events for ARIA menus.
if (target->IsARIARole(nsGkAtoms::menuitem)) {
// The focus was moved into menu.
LocalAccessible* ARIAMenubar = nullptr;
for (LocalAccessible* parent = target->LocalParent(); parent;
parent = parent->LocalParent()) {
if (parent->IsARIARole(nsGkAtoms::menubar)) {
ARIAMenubar = parent;
break;
}
// Go up in the parent chain of the menu hierarchy.
if (!parent->IsARIARole(nsGkAtoms::menuitem) &&
!parent->IsARIARole(nsGkAtoms::menu)) {
break;
}
}
if (ARIAMenubar != mActiveARIAMenubar) {
// Leaving ARIA menu. Fire menu_end event on current menubar.
if (mActiveARIAMenubar) {
RefPtr<AccEvent> menuEndEvent =
new AccEvent(nsIAccessibleEvent::EVENT_MENU_END, mActiveARIAMenubar,
aEvent->FromUserInput());
nsEventShell::FireEvent(menuEndEvent);
}
mActiveARIAMenubar = ARIAMenubar;
// Entering ARIA menu. Fire menu_start event.
if (mActiveARIAMenubar) {
RefPtr<AccEvent> menuStartEvent =
new AccEvent(nsIAccessibleEvent::EVENT_MENU_START,
mActiveARIAMenubar, aEvent->FromUserInput());
nsEventShell::FireEvent(menuStartEvent);
}
}
} else if (mActiveARIAMenubar) {
// Focus left a menu. Fire menu_end event.
RefPtr<AccEvent> menuEndEvent =
new AccEvent(nsIAccessibleEvent::EVENT_MENU_END, mActiveARIAMenubar,
aEvent->FromUserInput());
nsEventShell::FireEvent(menuEndEvent);
mActiveARIAMenubar = nullptr;
}
#ifdef A11Y_LOG
if (logging::IsEnabled(logging::eFocus)) {
logging::FocusNotificationTarget("fire focus event", "Target", target);
}
#endif
// Reset cached caret value. The cache will be updated upon processing the
// next caret move event. This ensures that we will return the correct caret
// offset before the caret move event is handled.
SelectionMgr()->ResetCaretOffset();
RefPtr<AccEvent> focusEvent = new AccEvent(nsIAccessibleEvent::EVENT_FOCUS,
target, aEvent->FromUserInput());
nsEventShell::FireEvent(focusEvent);
if (NS_WARN_IF(target->IsDefunct())) {
// target died during nsEventShell::FireEvent.
return;
}
// Fire scrolling_start event when the document receives the focus if it has
// an anchor jump. If an accessible within the document receive the focus
// then null out the anchor jump because it no longer applies.
DocAccessible* targetDocument = target->Document();
MOZ_ASSERT(targetDocument);
LocalAccessible* anchorJump = targetDocument->AnchorJump();
if (anchorJump) {
if (target == targetDocument || target->IsNonInteractive()) {
// we receive focus event, for example if the node is removed from DOM.
nsEventShell::FireEvent(nsIAccessibleEvent::EVENT_SCROLLING_START,
anchorJump, aEvent->FromUserInput());
}
targetDocument->SetAnchorJump(nullptr);
}
}
nsINode* FocusManager::FocusedDOMNode() const {
nsFocusManager* DOMFocusManager = nsFocusManager::GetFocusManager();
nsIContent* focusedElm = DOMFocusManager->GetFocusedElement();
nsIFrame* focusedFrame = focusedElm ? focusedElm->GetPrimaryFrame() : nullptr;
// DOM elements retain their focused state when they get styled as display:
// none/content or visibility: hidden. We should treat those cases as if those
// elements were removed, and focus on doc.
if (focusedFrame && focusedFrame->StyleVisibility()->IsVisible()) {
// Print preview documents don't get DocAccessibles, but we still want a11y
// focus to go somewhere useful. Therefore, we allow a11y focus to land on
// the OuterDocAccessible in this case.
// Note that this code only handles remote print preview documents.
if (EventStateManager::IsTopLevelRemoteTarget(focusedElm) &&
focusedElm->AsElement()->HasAttribute(u"printpreview"_ns)) {
return focusedElm;
}
// No focus on remote target elements like xul:browser having DOM focus and
// residing in chrome process because it means an element in content process
// keeps the focus. Similarly, suppress focus on OOP iframes because an
// element in another content process should now have the focus.
if (EventStateManager::IsRemoteTarget(focusedElm)) {
return nullptr;
}
return focusedElm;
}
// Otherwise the focus can be on DOM document.
dom::BrowsingContext* context = DOMFocusManager->GetFocusedBrowsingContext();
if (context) {
// GetDocShell will return null if the document isn't in our process.
nsIDocShell* shell = context->GetDocShell();
if (shell) {
return shell->GetDocument();
}
}
// Focus isn't in this process.
return nullptr;
}
dom::Document* FocusManager::FocusedDOMDocument() const {
nsINode* focusedNode = FocusedDOMNode();
return focusedNode ? focusedNode->OwnerDoc() : nullptr;
}
} // namespace a11y
} // namespace mozilla