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// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/browser/accessibility/browser_accessibility_manager_mac.h"
#import "base/logging.h"
#import "content/browser/accessibility/browser_accessibility_cocoa.h"
#import "content/browser/accessibility/browser_accessibility_mac.h"
#include "content/common/accessibility_messages.h"
namespace content {
// static
BrowserAccessibilityManager* BrowserAccessibilityManager::Create(
const ui::AXTreeUpdate& initial_tree,
BrowserAccessibilityDelegate* delegate,
BrowserAccessibilityFactory* factory) {
return new BrowserAccessibilityManagerMac(
NULL, initial_tree, delegate, factory);
}
BrowserAccessibilityManagerMac::BrowserAccessibilityManagerMac(
NSView* parent_view,
const ui::AXTreeUpdate& initial_tree,
BrowserAccessibilityDelegate* delegate,
BrowserAccessibilityFactory* factory)
: BrowserAccessibilityManager(delegate, factory),
parent_view_(parent_view),
created_live_region_(false) {
Initialize(initial_tree);
}
// static
ui::AXTreeUpdate BrowserAccessibilityManagerMac::GetEmptyDocument() {
ui::AXNodeData empty_document;
empty_document.id = 0;
empty_document.role = ui::AX_ROLE_ROOT_WEB_AREA;
empty_document.state =
1 << ui::AX_STATE_READ_ONLY;
ui::AXTreeUpdate update;
update.nodes.push_back(empty_document);
return update;
}
BrowserAccessibility* BrowserAccessibilityManagerMac::GetFocus(
BrowserAccessibility* root) {
BrowserAccessibility* node = GetActiveDescendantFocus(root);
return node;
}
void BrowserAccessibilityManagerMac::NotifyAccessibilityEvent(
ui::AXEvent event_type,
BrowserAccessibility* node) {
if (!node->IsNative())
return;
// Refer to AXObjectCache.mm (webkit).
NSString* event_id = @"";
switch (event_type) {
case ui::AX_EVENT_ACTIVEDESCENDANTCHANGED:
if (node->GetRole() == ui::AX_ROLE_TREE) {
event_id = NSAccessibilitySelectedRowsChangedNotification;
} else {
event_id = NSAccessibilityFocusedUIElementChangedNotification;
BrowserAccessibility* active_descendant_focus =
GetActiveDescendantFocus(GetRoot());
if (active_descendant_focus)
node = active_descendant_focus;
}
break;
case ui::AX_EVENT_ALERT:
// Not used on Mac.
return;
case ui::AX_EVENT_BLUR:
// A no-op on Mac.
return;
case ui::AX_EVENT_CHECKED_STATE_CHANGED:
// Not used on Mac.
return;
case ui::AX_EVENT_CHILDREN_CHANGED:
// TODO(dtseng): no clear equivalent on Mac.
return;
case ui::AX_EVENT_FOCUS:
event_id = NSAccessibilityFocusedUIElementChangedNotification;
break;
case ui::AX_EVENT_LAYOUT_COMPLETE:
event_id = @"AXLayoutComplete";
break;
case ui::AX_EVENT_LIVE_REGION_CHANGED:
event_id = @"AXLiveRegionChanged";
break;
case ui::AX_EVENT_LOAD_COMPLETE:
event_id = @"AXLoadComplete";
break;
case ui::AX_EVENT_MENU_LIST_VALUE_CHANGED:
// Not used on Mac.
return;
case ui::AX_EVENT_ROW_COUNT_CHANGED:
event_id = NSAccessibilityRowCountChangedNotification;
break;
case ui::AX_EVENT_ROW_COLLAPSED:
event_id = @"AXRowCollapsed";
break;
case ui::AX_EVENT_ROW_EXPANDED:
event_id = @"AXRowExpanded";
break;
case ui::AX_EVENT_SCROLLED_TO_ANCHOR:
// Not used on Mac.
return;
case ui::AX_EVENT_SELECTED_CHILDREN_CHANGED:
event_id = NSAccessibilitySelectedChildrenChangedNotification;
break;
case ui::AX_EVENT_TEXT_SELECTION_CHANGED:
event_id = NSAccessibilitySelectedTextChangedNotification;
break;
case ui::AX_EVENT_VALUE_CHANGED:
event_id = NSAccessibilityValueChangedNotification;
break;
case ui::AX_EVENT_ARIA_ATTRIBUTE_CHANGED:
// Not used on Mac.
return;
case ui::AX_EVENT_AUTOCORRECTION_OCCURED:
// Not used on Mac.
return;
case ui::AX_EVENT_INVALID_STATUS_CHANGED:
// Not used on Mac.
return;
case ui::AX_EVENT_LOCATION_CHANGED:
// Not used on Mac.
return;
case ui::AX_EVENT_MENU_LIST_ITEM_SELECTED:
// Not used on Mac.
return;
case ui::AX_EVENT_TEXT_CHANGED:
// Not used on Mac.
return;
default:
LOG(WARNING) << "Unknown accessibility event: " << event_type;
return;
}
BrowserAccessibilityCocoa* native_node = node->ToBrowserAccessibilityCocoa();
DCHECK(native_node);
NSAccessibilityPostNotification(native_node, event_id);
}
void BrowserAccessibilityManagerMac::OnNodeCreationFinished(ui::AXNode* node) {
BrowserAccessibility* obj = GetFromAXNode(node);
if (obj && obj->HasStringAttribute(ui::AX_ATTR_LIVE_STATUS))
created_live_region_ = true;
}
void BrowserAccessibilityManagerMac::OnTreeUpdateFinished() {
if (!created_live_region_)
return;
// This code is to work around a bug in VoiceOver, where a new live
// region that gets added is ignored. VoiceOver seems to only scan the
// page for live regions once. By recreating the NSAccessibility
// object for the root of the tree, we force VoiceOver to clear out its
// internal state and find newly-added live regions this time.
BrowserAccessibilityMac* root =
static_cast<BrowserAccessibilityMac*>(GetRoot());
root->RecreateNativeObject();
NotifyAccessibilityEvent(ui::AX_EVENT_CHILDREN_CHANGED, root);
created_live_region_ = false;
}
} // namespace content
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