| // 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_win.h" |
| |
| #include "base/command_line.h" |
| #include "base/win/scoped_comptr.h" |
| #include "base/win/windows_version.h" |
| #include "content/browser/accessibility/browser_accessibility_state_impl.h" |
| #include "content/browser/accessibility/browser_accessibility_win.h" |
| #include "content/browser/renderer_host/legacy_render_widget_host_win.h" |
| #include "content/common/accessibility_messages.h" |
| #include "ui/base/win/atl_module.h" |
| |
| namespace content { |
| |
| // static |
| BrowserAccessibilityManager* BrowserAccessibilityManager::Create( |
| const ui::AXTreeUpdate& initial_tree, |
| BrowserAccessibilityDelegate* delegate, |
| BrowserAccessibilityFactory* factory) { |
| return new BrowserAccessibilityManagerWin( |
| content::LegacyRenderWidgetHostHWND::Create(GetDesktopWindow()).get(), |
| NULL, initial_tree, delegate, factory); |
| } |
| |
| BrowserAccessibilityManagerWin* |
| BrowserAccessibilityManager::ToBrowserAccessibilityManagerWin() { |
| return static_cast<BrowserAccessibilityManagerWin*>(this); |
| } |
| |
| BrowserAccessibilityManagerWin::BrowserAccessibilityManagerWin( |
| LegacyRenderWidgetHostHWND* accessible_hwnd, |
| IAccessible* parent_iaccessible, |
| const ui::AXTreeUpdate& initial_tree, |
| BrowserAccessibilityDelegate* delegate, |
| BrowserAccessibilityFactory* factory) |
| : BrowserAccessibilityManager(initial_tree, delegate, factory), |
| parent_hwnd_(NULL), |
| parent_iaccessible_(parent_iaccessible), |
| tracked_scroll_object_(NULL), |
| accessible_hwnd_(accessible_hwnd), |
| focus_event_on_root_needed_(false) { |
| ui::win::CreateATLModuleIfNeeded(); |
| if (accessible_hwnd_) { |
| accessible_hwnd_->set_browser_accessibility_manager(this); |
| parent_hwnd_ = accessible_hwnd_->GetParent(); |
| } |
| } |
| |
| BrowserAccessibilityManagerWin::~BrowserAccessibilityManagerWin() { |
| if (tracked_scroll_object_) { |
| tracked_scroll_object_->Release(); |
| tracked_scroll_object_ = NULL; |
| } |
| if (accessible_hwnd_) |
| accessible_hwnd_->OnManagerDeleted(); |
| } |
| |
| // static |
| ui::AXTreeUpdate BrowserAccessibilityManagerWin::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_ENABLED) | |
| (1 << ui::AX_STATE_READ_ONLY) | |
| (1 << ui::AX_STATE_BUSY); |
| |
| ui::AXTreeUpdate update; |
| update.nodes.push_back(empty_document); |
| return update; |
| } |
| |
| void BrowserAccessibilityManagerWin::SetAccessibleHWND( |
| LegacyRenderWidgetHostHWND* accessible_hwnd) { |
| accessible_hwnd_ = accessible_hwnd; |
| if (accessible_hwnd_) { |
| accessible_hwnd_->set_browser_accessibility_manager(this); |
| parent_hwnd_ = accessible_hwnd_->GetParent(); |
| } |
| } |
| |
| void BrowserAccessibilityManagerWin::MaybeCallNotifyWinEvent(DWORD event, |
| LONG child_id) { |
| // If on Win 7 and complete accessibility is enabled, use the fake child HWND |
| // to use as the root of the accessibility tree. See comments above |
| // LegacyRenderWidgetHostHWND for details. |
| if (accessible_hwnd_ && |
| BrowserAccessibilityStateImpl::GetInstance()->IsAccessibleBrowser()) { |
| parent_hwnd_ = accessible_hwnd_->hwnd(); |
| parent_iaccessible_ = accessible_hwnd_->window_accessible(); |
| } |
| |
| // Only fire events if this view is hooked up to its parent. |
| if (parent_iaccessible() && parent_hwnd()) |
| ::NotifyWinEvent(event, parent_hwnd(), OBJID_CLIENT, child_id); |
| } |
| |
| |
| void BrowserAccessibilityManagerWin::OnNodeCreated(ui::AXNode* node) { |
| BrowserAccessibilityManager::OnNodeCreated(node); |
| BrowserAccessibility* obj = GetFromAXNode(node); |
| LONG unique_id_win = obj->ToBrowserAccessibilityWin()->unique_id_win(); |
| unique_id_to_ax_id_map_[unique_id_win] = obj->GetId(); |
| } |
| |
| void BrowserAccessibilityManagerWin::OnNodeWillBeDeleted(ui::AXNode* node) { |
| BrowserAccessibilityManager::OnNodeWillBeDeleted(node); |
| BrowserAccessibility* obj = GetFromAXNode(node); |
| if (!obj) |
| return; |
| unique_id_to_ax_id_map_.erase( |
| obj->ToBrowserAccessibilityWin()->unique_id_win()); |
| if (obj == tracked_scroll_object_) { |
| tracked_scroll_object_->Release(); |
| tracked_scroll_object_ = NULL; |
| } |
| } |
| |
| void BrowserAccessibilityManagerWin::OnWindowFocused() { |
| // This is called either when this web frame gets focused, or when |
| // the root of the accessibility tree changes. In both cases, we need |
| // to fire a focus event on the root and then on the focused element |
| // within the page, if different. |
| |
| // Set this flag so that we'll keep trying to fire these focus events |
| // if they're not successful this time. |
| focus_event_on_root_needed_ = true; |
| |
| if (!delegate_ || !delegate_->AccessibilityViewHasFocus()) |
| return; |
| |
| // Try to fire a focus event on the root first and then the focused node. |
| // This will clear focus_event_on_root_needed_ if successful. |
| if (focus_ != tree_->GetRoot()) |
| NotifyAccessibilityEvent(ui::AX_EVENT_FOCUS, GetRoot()); |
| BrowserAccessibilityManager::OnWindowFocused(); |
| } |
| |
| void BrowserAccessibilityManagerWin::NotifyAccessibilityEvent( |
| ui::AXEvent event_type, |
| BrowserAccessibility* node) { |
| if (node->GetRole() == ui::AX_ROLE_INLINE_TEXT_BOX) |
| return; |
| |
| // Don't fire focus, blur, or load complete notifications if the |
| // window isn't focused, because that can confuse screen readers into |
| // entering their "browse" mode. |
| if ((event_type == ui::AX_EVENT_FOCUS || |
| event_type == ui::AX_EVENT_BLUR || |
| event_type == ui::AX_EVENT_LOAD_COMPLETE) && |
| (!delegate_ || !delegate_->AccessibilityViewHasFocus())) { |
| return; |
| } |
| |
| // NVDA gets confused if we focus the main document element when it hasn't |
| // finished loading and it has no children at all, so suppress that event. |
| if (event_type == ui::AX_EVENT_FOCUS && |
| node == GetRoot() && |
| node->PlatformChildCount() == 0 && |
| !node->HasState(ui::AX_STATE_BUSY) && |
| !node->GetBoolAttribute(ui::AX_ATTR_DOC_LOADED)) { |
| return; |
| } |
| |
| // If a focus event is needed on the root, fire that first before |
| // this event. |
| if (event_type == ui::AX_EVENT_FOCUS && node == GetRoot()) |
| focus_event_on_root_needed_ = false; |
| else if (focus_event_on_root_needed_) |
| OnWindowFocused(); |
| |
| LONG event_id = EVENT_MIN; |
| switch (event_type) { |
| case ui::AX_EVENT_ACTIVEDESCENDANTCHANGED: |
| event_id = IA2_EVENT_ACTIVE_DESCENDANT_CHANGED; |
| break; |
| case ui::AX_EVENT_ALERT: |
| event_id = EVENT_SYSTEM_ALERT; |
| break; |
| case ui::AX_EVENT_ARIA_ATTRIBUTE_CHANGED: |
| event_id = IA2_EVENT_OBJECT_ATTRIBUTE_CHANGED; |
| break; |
| case ui::AX_EVENT_AUTOCORRECTION_OCCURED: |
| event_id = IA2_EVENT_OBJECT_ATTRIBUTE_CHANGED; |
| break; |
| case ui::AX_EVENT_BLUR: |
| // Equivalent to focus on the root. |
| event_id = EVENT_OBJECT_FOCUS; |
| node = GetRoot(); |
| break; |
| case ui::AX_EVENT_CHECKED_STATE_CHANGED: |
| event_id = EVENT_OBJECT_STATECHANGE; |
| break; |
| case ui::AX_EVENT_CHILDREN_CHANGED: |
| event_id = EVENT_OBJECT_REORDER; |
| break; |
| case ui::AX_EVENT_FOCUS: |
| event_id = EVENT_OBJECT_FOCUS; |
| break; |
| case ui::AX_EVENT_INVALID_STATUS_CHANGED: |
| event_id = EVENT_OBJECT_STATECHANGE; |
| break; |
| case ui::AX_EVENT_LIVE_REGION_CHANGED: |
| if (node->GetBoolAttribute(ui::AX_ATTR_CONTAINER_LIVE_BUSY)) |
| return; |
| event_id = EVENT_OBJECT_LIVEREGIONCHANGED; |
| break; |
| case ui::AX_EVENT_LOAD_COMPLETE: |
| event_id = IA2_EVENT_DOCUMENT_LOAD_COMPLETE; |
| break; |
| case ui::AX_EVENT_MENU_LIST_ITEM_SELECTED: |
| event_id = EVENT_OBJECT_FOCUS; |
| break; |
| case ui::AX_EVENT_MENU_LIST_VALUE_CHANGED: |
| event_id = EVENT_OBJECT_VALUECHANGE; |
| break; |
| case ui::AX_EVENT_HIDE: |
| event_id = EVENT_OBJECT_HIDE; |
| break; |
| case ui::AX_EVENT_SHOW: |
| event_id = EVENT_OBJECT_SHOW; |
| break; |
| case ui::AX_EVENT_SCROLL_POSITION_CHANGED: |
| event_id = EVENT_SYSTEM_SCROLLINGEND; |
| break; |
| case ui::AX_EVENT_SCROLLED_TO_ANCHOR: |
| event_id = EVENT_SYSTEM_SCROLLINGSTART; |
| break; |
| case ui::AX_EVENT_SELECTED_CHILDREN_CHANGED: |
| event_id = EVENT_OBJECT_SELECTIONWITHIN; |
| break; |
| case ui::AX_EVENT_SELECTED_TEXT_CHANGED: |
| event_id = IA2_EVENT_TEXT_CARET_MOVED; |
| break; |
| case ui::AX_EVENT_TEXT_CHANGED: |
| event_id = EVENT_OBJECT_NAMECHANGE; |
| break; |
| case ui::AX_EVENT_TEXT_INSERTED: |
| event_id = IA2_EVENT_TEXT_INSERTED; |
| break; |
| case ui::AX_EVENT_TEXT_REMOVED: |
| event_id = IA2_EVENT_TEXT_REMOVED; |
| break; |
| case ui::AX_EVENT_VALUE_CHANGED: |
| event_id = EVENT_OBJECT_VALUECHANGE; |
| break; |
| default: |
| // Not all WebKit accessibility events result in a Windows |
| // accessibility notification. |
| break; |
| } |
| |
| if (event_id != EVENT_MIN) { |
| // Pass the node's unique id in the |child_id| argument to NotifyWinEvent; |
| // the AT client will then call get_accChild on the HWND's accessibility |
| // object and pass it that same id, which we can use to retrieve the |
| // IAccessible for this node. |
| LONG child_id = node->ToBrowserAccessibilityWin()->unique_id_win(); |
| MaybeCallNotifyWinEvent(event_id, child_id); |
| } |
| |
| // If this is a layout complete notification (sent when a container scrolls) |
| // and there is a descendant tracked object, send a notification on it. |
| // TODO(dmazzoni): remove once http://crbug.com/113483 is fixed. |
| if (event_type == ui::AX_EVENT_LAYOUT_COMPLETE && |
| tracked_scroll_object_ && |
| tracked_scroll_object_->IsDescendantOf(node)) { |
| MaybeCallNotifyWinEvent( |
| IA2_EVENT_VISIBLE_DATA_CHANGED, |
| tracked_scroll_object_->ToBrowserAccessibilityWin()->unique_id_win()); |
| tracked_scroll_object_->Release(); |
| tracked_scroll_object_ = NULL; |
| } |
| } |
| |
| void BrowserAccessibilityManagerWin::OnRootChanged(ui::AXNode* new_root) { |
| // In order to make screen readers aware of the new accessibility root, |
| // we need to fire a focus event on it. |
| OnWindowFocused(); |
| } |
| |
| void BrowserAccessibilityManagerWin::TrackScrollingObject( |
| BrowserAccessibilityWin* node) { |
| if (tracked_scroll_object_) |
| tracked_scroll_object_->Release(); |
| tracked_scroll_object_ = node; |
| tracked_scroll_object_->AddRef(); |
| } |
| |
| BrowserAccessibilityWin* BrowserAccessibilityManagerWin::GetFromUniqueIdWin( |
| LONG unique_id_win) { |
| base::hash_map<LONG, int32>::iterator iter = |
| unique_id_to_ax_id_map_.find(unique_id_win); |
| if (iter != unique_id_to_ax_id_map_.end()) { |
| BrowserAccessibility* result = GetFromID(iter->second); |
| if (result) |
| return result->ToBrowserAccessibilityWin(); |
| } |
| return NULL; |
| } |
| |
| void BrowserAccessibilityManagerWin::OnAccessibleHwndDeleted() { |
| // If the AccessibleHWND is deleted, |parent_hwnd_| and |
| // |parent_iaccessible_| are no longer valid either, since they were |
| // derived from AccessibleHWND. We don't have to restore them to |
| // previous values, though, because this should only happen |
| // during the destruct sequence for this window. |
| accessible_hwnd_ = NULL; |
| parent_hwnd_ = NULL; |
| parent_iaccessible_ = NULL; |
| } |
| |
| } // namespace content |