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Public Member Functions | Protected Member Functions | List of all members
flutter::AccessibilityBridgeWindows Class Reference

`#include <accessibility_bridge_windows.h>`

Inheritance diagram for flutter::AccessibilityBridgeWindows:

## Public Member Functions
| AccessibilityBridgeWindows (FlutterWindowsView *view)
virtual | ~AccessibilityBridgeWindows ()=default
void | DispatchAccessibilityAction (AccessibilityNodeId target, FlutterSemanticsAction action, fml::MallocMapping data) override
| Dispatch accessibility action back to the Flutter framework. These actions are generated in the native accessibility system when users interact with the assistive technologies. For example, a FlutterSemanticsAction::kFlutterSemanticsActionTap is fired when user click or touch the screen. More...
virtual void | DispatchWinAccessibilityEvent (std::shared_ptr< FlutterPlatformNodeDelegateWindows > node_delegate, ax::mojom::Event event_type)
virtual void | SetFocus (std::shared_ptr< FlutterPlatformNodeDelegateWindows > node_delegate)
gfx::NativeViewAccessible | GetChildOfAXFragmentRoot () override
gfx::NativeViewAccessible | GetParentOfAXFragmentRoot () override
bool | IsAXFragmentRootAControlElement () override
Public Member Functions inherited from flutter::AccessibilityBridge
| AccessibilityBridge ()
| Creates a new instance of a accessibility bridge. More...
virtual | ~AccessibilityBridge ()
void | AddFlutterSemanticsNodeUpdate (const FlutterSemanticsNode2 &node)
| Adds a semantics node update to the pending semantics update. Calling this method alone will NOT update the semantics tree. To flush the pending updates, call the CommitUpdates(). More...
void | AddFlutterSemanticsCustomActionUpdate (const FlutterSemanticsCustomAction2 &action)
| Adds a custom semantics action update to the pending semantics update. Calling this method alone will NOT update the semantics tree. To flush the pending updates, call the CommitUpdates(). More...
void | CommitUpdates ()
| Flushes the pending updates and applies them to this accessibility bridge. Calling this with no pending updates does nothing, and callers should call this method at the end of an atomic batch to avoid leaving the tree in a unstable state. For example if a node reparents from A to B, callers should only call this method when both removal from A and addition to B are in the pending updates. More...
std::weak_ptr< FlutterPlatformNodeDelegate > | GetFlutterPlatformNodeDelegateFromID (AccessibilityNodeId id) const
| Get the flutter platform node delegate with the given id from this accessibility bridge. Returns expired weak_ptr if the delegate associated with the id does not exist or has been removed from the accessibility tree. More...
const ui::AXTreeData & | GetAXTreeData () const
| Get the ax tree data from this accessibility bridge. The tree data contains information such as the id of the node that has the keyboard focus or the text selection range. More...
const std::vector< ui::AXEventGenerator::TargetedEvent > | GetPendingEvents () const
| Gets all pending accessibility events generated during semantics updates. This is useful when deciding how to handle events in AccessibilityBridgeDelegate::OnAccessibilityEvent in case one may decide to handle an event differently based on all pending events. More...
ui::AXNode * | GetNodeFromTree (const ui::AXTreeID tree_id, const ui::AXNode::AXID node_id) const override
ui::AXNode * | GetNodeFromTree (const ui::AXNode::AXID node_id) const override
ui::AXTreeID | GetTreeID () const override
ui::AXTreeID | GetParentTreeID () const override
ui::AXNode * | GetRootAsAXNode () const override
ui::AXNode * | GetParentNodeFromParentTreeAsAXNode () const override
ui::AXTree * | GetTree () const override
ui::AXPlatformNode * | GetPlatformNodeFromTree (const ui::AXNode::AXID node_id) const override
ui::AXPlatformNode * | GetPlatformNodeFromTree (const ui::AXNode &node) const override
ui::AXPlatformNodeDelegate * | RootDelegate () const override
Public Member Functions inherited from flutter::FlutterPlatformNodeDelegate::OwnerBridge
virtual | ~OwnerBridge ()=default

## Protected Member Functions
void | OnAccessibilityEvent (ui::AXEventGenerator::TargetedEvent targeted_event) override
| Handle accessibility events generated due to accessibility tree changes. These events are needed to be sent to native accessibility system. See ui::AXEventGenerator::Event for possible events. More...
std::shared_ptr< FlutterPlatformNodeDelegate > | CreateFlutterPlatformNodeDelegate () override
| Creates a platform specific FlutterPlatformNodeDelegate. Ownership passes to the caller. This method will be called whenever a new AXNode is created in AXTree. Each platform needs to implement this method in order to inject its subclass into the accessibility bridge. More...
virtual std::weak_ptr< FlutterPlatformNodeDelegate > | GetFocusedNode ()

## Detailed Description

AccessibilityBridgeWindows must be created as a shared_ptr, since some methods acquires its weak_ptr.

Definition at line 27 of file accessibility_bridge_windows.h.

## Constructor & Destructor Documentation

## ◆ AccessibilityBridgeWindows()

flutter::AccessibilityBridgeWindows::AccessibilityBridgeWindows | ( | FlutterWindowsView * | view | ) |

Definition at line 13 of file accessibility_bridge_windows.cc.

14 : view_(view) {
15 FML_DCHECK(view_);
16 }

## ◆ ~AccessibilityBridgeWindows()

virtual flutter::AccessibilityBridgeWindows::~AccessibilityBridgeWindows | ( |  | ) |
| virtual default

## Member Function Documentation

## ◆ CreateFlutterPlatformNodeDelegate()

std::shared_ptr< FlutterPlatformNodeDelegate > flutter::AccessibilityBridgeWindows::CreateFlutterPlatformNodeDelegate | ( |  | ) |
| override protected virtual

Creates a platform specific FlutterPlatformNodeDelegate. Ownership passes to the caller. This method will be called whenever a new AXNode is created in AXTree. Each platform needs to implement this method in order to inject its subclass into the accessibility bridge.

Implements flutter::AccessibilityBridge.

Definition at line 170 of file accessibility_bridge_windows.cc.

170 {
171 return std::make_shared<FlutterPlatformNodeDelegateWindows>(
172 shared_from_this(), view_);
173 }

## ◆ DispatchAccessibilityAction()

void flutter::AccessibilityBridgeWindows::DispatchAccessibilityAction | ( | AccessibilityNodeId | target,
|  | FlutterSemanticsAction | action,
|  | fml::MallocMapping | data
| ) |  |
| override virtual

Dispatch accessibility action back to the Flutter framework. These actions are generated in the native accessibility system when users interact with the assistive technologies. For example, a FlutterSemanticsAction::kFlutterSemanticsActionTap is fired when user click or touch the screen.

Parameters

  [in] | target | The semantics node id of the action target.
  [in] | action | The generated flutter semantics action.
  [in] | data | Additional data associated with the action.

Implements flutter::FlutterPlatformNodeDelegate::OwnerBridge.

Definition at line 162 of file accessibility_bridge_windows.cc.

165 {
166 view_->GetEngine()->DispatchSemanticsAction(target, action, std::move(data));
167 }

References action, flutter::FlutterWindowsEngine::DispatchSemanticsAction(), and flutter::FlutterWindowsView::GetEngine().

Referenced by flutter::testing::TEST().

## ◆ DispatchWinAccessibilityEvent()

void flutter::AccessibilityBridgeWindows::DispatchWinAccessibilityEvent | ( | std::shared_ptr< FlutterPlatformNodeDelegateWindows > | node_delegate,
|  | ax::mojom::Event | event_type
| ) |  |
| virtual

Definition at line 175 of file accessibility_bridge_windows.cc.

177 {
178 node_delegate->DispatchWinAccessibilityEvent(event_type);
179 }

References event_type, and node_delegate.

Referenced by OnAccessibilityEvent().

## ◆ GetChildOfAXFragmentRoot()

gfx::NativeViewAccessible flutter::AccessibilityBridgeWindows::GetChildOfAXFragmentRoot | ( |  | ) |
| override

Definition at line 187 of file accessibility_bridge_windows.cc.

187 {
188 ui::AXPlatformNodeDelegate* root_delegate = RootDelegate();
189 if (!root_delegate) {
190 return nullptr;
191 }
192
193 return root_delegate->GetNativeViewAccessible();
194 }

References flutter::AccessibilityBridge::RootDelegate().

## ◆ GetFocusedNode()

std::weak_ptr< FlutterPlatformNodeDelegate > flutter::AccessibilityBridgeWindows::GetFocusedNode | ( |  | ) |
| protected virtual

Definition at line 206 of file accessibility_bridge_windows.cc.

206 {
207 ui::AXNode::AXID focus_id = GetAXTreeData().sel_focus_object_id;
208 return GetFlutterPlatformNodeDelegateFromID(focus_id);
209 }

References flutter::AccessibilityBridge::GetAXTreeData(), and flutter::AccessibilityBridge::GetFlutterPlatformNodeDelegateFromID().

Referenced by OnAccessibilityEvent().

## ◆ GetParentOfAXFragmentRoot()

gfx::NativeViewAccessible flutter::AccessibilityBridgeWindows::GetParentOfAXFragmentRoot | ( |  | ) |
| override

Definition at line 197 of file accessibility_bridge_windows.cc.

197 {
198 return nullptr;
199 }

## ◆ IsAXFragmentRootAControlElement()

bool flutter::AccessibilityBridgeWindows::IsAXFragmentRootAControlElement | ( |  | ) |
| override

Definition at line 201 of file accessibility_bridge_windows.cc.

201 {
202 return true;
203 }

## ◆ OnAccessibilityEvent()

void flutter::AccessibilityBridgeWindows::OnAccessibilityEvent | ( | ui::AXEventGenerator::TargetedEvent | targeted_event | ) |
| override protected virtual

Handle accessibility events generated due to accessibility tree changes. These events are needed to be sent to native accessibility system. See ui::AXEventGenerator::Event for possible events.

Parameters

  [in] | targeted_event | The object that contains both the generated event and the event target.

Implements flutter::AccessibilityBridge.

Definition at line 18 of file accessibility_bridge_windows.cc.

19 {
20 ui::AXNode* ax_node = targeted_event.node;
21 ui::AXEventGenerator::Event event_type = targeted_event.event_params.event;
22
23 auto node_delegate =
24 GetFlutterPlatformNodeDelegateFromID(ax_node->id()).lock();
25 FML_DCHECK(node_delegate)
26 << "No FlutterPlatformNodeDelegate found for node ID " << ax_node->id();
27 std::shared_ptr<FlutterPlatformNodeDelegateWindows> win_delegate =
28 std::static_pointer_cast<FlutterPlatformNodeDelegateWindows>(
29 node_delegate);
30
31 switch (event_type) {
32 case ui::AXEventGenerator::Event::ALERT:
33 DispatchWinAccessibilityEvent(win_delegate, ax::mojom::Event::kAlert);
34 break;
35 case ui::AXEventGenerator::Event::CHECKED_STATE_CHANGED:
36 DispatchWinAccessibilityEvent(win_delegate,
37 ax::mojom::Event::kValueChanged);
38 break;
39 case ui::AXEventGenerator::Event::CHILDREN_CHANGED:
40 DispatchWinAccessibilityEvent(win_delegate,
41 ax::mojom::Event::kChildrenChanged);
42 break;
43 case ui::AXEventGenerator::Event::DOCUMENT_SELECTION_CHANGED: {
44 // An event indicating a change in document selection should be fired
45 // only for the focused node whose selection has changed. If a valid
46 // caret and selection exist in the app tree, they must both be within
47 // the focus node.
48 auto focus_delegate = GetFocusedNode().lock();
49 if (focus_delegate) {
50 win_delegate =
51 std::static_pointer_cast<FlutterPlatformNodeDelegateWindows>(
52 focus_delegate);
53 }
54 DispatchWinAccessibilityEvent(
55 win_delegate, ax::mojom::Event::kDocumentSelectionChanged);
56 break;
57 }
58 case ui::AXEventGenerator::Event::FOCUS_CHANGED:
59 DispatchWinAccessibilityEvent(win_delegate, ax::mojom::Event::kFocus);
60 SetFocus(win_delegate);
61 break;
62 case ui::AXEventGenerator::Event::IGNORED_CHANGED:
63 if (ax_node->IsIgnored()) {
64 DispatchWinAccessibilityEvent(win_delegate, ax::mojom::Event::kHide);
65 }
66 break;
67 case ui::AXEventGenerator::Event::IMAGE_ANNOTATION_CHANGED:
68 DispatchWinAccessibilityEvent(win_delegate,
69 ax::mojom::Event::kTextChanged);
70 break;
71 case ui::AXEventGenerator::Event::LIVE_REGION_CHANGED:
72 DispatchWinAccessibilityEvent(win_delegate,
73 ax::mojom::Event::kLiveRegionChanged);
74 break;
75 case ui::AXEventGenerator::Event::NAME_CHANGED:
76 DispatchWinAccessibilityEvent(win_delegate,
77 ax::mojom::Event::kTextChanged);
78 break;
79 case ui::AXEventGenerator::Event::SCROLL_HORIZONTAL_POSITION_CHANGED:
80 DispatchWinAccessibilityEvent(win_delegate,
81 ax::mojom::Event::kScrollPositionChanged);
82 break;
83 case ui::AXEventGenerator::Event::SCROLL_VERTICAL_POSITION_CHANGED:
84 DispatchWinAccessibilityEvent(win_delegate,
85 ax::mojom::Event::kScrollPositionChanged);
86 break;
87 case ui::AXEventGenerator::Event::SELECTED_CHANGED:
88 DispatchWinAccessibilityEvent(win_delegate,
89 ax::mojom::Event::kValueChanged);
90 break;
91 case ui::AXEventGenerator::Event::SELECTED_CHILDREN_CHANGED:
92 DispatchWinAccessibilityEvent(win_delegate,
93 ax::mojom::Event::kSelectedChildrenChanged);
94 break;
95 case ui::AXEventGenerator::Event::SUBTREE_CREATED:
96 DispatchWinAccessibilityEvent(win_delegate, ax::mojom::Event::kShow);
97 break;
98 case ui::AXEventGenerator::Event::VALUE_CHANGED:
99 DispatchWinAccessibilityEvent(win_delegate,
100 ax::mojom::Event::kValueChanged);
101 break;
102 case ui::AXEventGenerator::Event::WIN_IACCESSIBLE_STATE_CHANGED:
103 DispatchWinAccessibilityEvent(win_delegate,
104 ax::mojom::Event::kStateChanged);
105 break;
106 case ui::AXEventGenerator::Event::ACCESS_KEY_CHANGED:
107 case ui::AXEventGenerator::Event::ACTIVE_DESCENDANT_CHANGED:
108 case ui::AXEventGenerator::Event::ATK_TEXT_OBJECT_ATTRIBUTE_CHANGED:
109 case ui::AXEventGenerator::Event::ATOMIC_CHANGED:
110 case ui::AXEventGenerator::Event::AUTO_COMPLETE_CHANGED:
111 case ui::AXEventGenerator::Event::BUSY_CHANGED:
112 case ui::AXEventGenerator::Event::CLASS_NAME_CHANGED:
113 case ui::AXEventGenerator::Event::COLLAPSED:
114 case ui::AXEventGenerator::Event::CONTROLS_CHANGED:
115 case ui::AXEventGenerator::Event::DESCRIBED_BY_CHANGED:
116 case ui::AXEventGenerator::Event::DESCRIPTION_CHANGED:
117 case ui::AXEventGenerator::Event::DOCUMENT_TITLE_CHANGED:
118 case ui::AXEventGenerator::Event::DROPEFFECT_CHANGED:
119 case ui::AXEventGenerator::Event::ENABLED_CHANGED:
120 case ui::AXEventGenerator::Event::EXPANDED:
121 case ui::AXEventGenerator::Event::FLOW_FROM_CHANGED:
122 case ui::AXEventGenerator::Event::FLOW_TO_CHANGED:
123 case ui::AXEventGenerator::Event::GRABBED_CHANGED:
124 case ui::AXEventGenerator::Event::HASPOPUP_CHANGED:
125 case ui::AXEventGenerator::Event::HIERARCHICAL_LEVEL_CHANGED:
126 case ui::AXEventGenerator::Event::INVALID_STATUS_CHANGED:
127 case ui::AXEventGenerator::Event::KEY_SHORTCUTS_CHANGED:
128 case ui::AXEventGenerator::Event::LABELED_BY_CHANGED:
129 case ui::AXEventGenerator::Event::LANGUAGE_CHANGED:
130 case ui::AXEventGenerator::Event::LAYOUT_INVALIDATED:
131 case ui::AXEventGenerator::Event::LIVE_REGION_CREATED:
132 case ui::AXEventGenerator::Event::LIVE_REGION_NODE_CHANGED:
133 case ui::AXEventGenerator::Event::LIVE_RELEVANT_CHANGED:
134 case ui::AXEventGenerator::Event::LIVE_STATUS_CHANGED:
135 case ui::AXEventGenerator::Event::LOAD_COMPLETE:
136 case ui::AXEventGenerator::Event::LOAD_START:
137 case ui::AXEventGenerator::Event::MENU_ITEM_SELECTED:
138 case ui::AXEventGenerator::Event::MULTILINE_STATE_CHANGED:
139 case ui::AXEventGenerator::Event::MULTISELECTABLE_STATE_CHANGED:
140 case ui::AXEventGenerator::Event::OBJECT_ATTRIBUTE_CHANGED:
141 case ui::AXEventGenerator::Event::OTHER_ATTRIBUTE_CHANGED:
142 case ui::AXEventGenerator::Event::PLACEHOLDER_CHANGED:
143 case ui::AXEventGenerator::Event::PORTAL_ACTIVATED:
144 case ui::AXEventGenerator::Event::POSITION_IN_SET_CHANGED:
145 case ui::AXEventGenerator::Event::READONLY_CHANGED:
146 case ui::AXEventGenerator::Event::RELATED_NODE_CHANGED:
147 case ui::AXEventGenerator::Event::REQUIRED_STATE_CHANGED:
148 case ui::AXEventGenerator::Event::ROLE_CHANGED:
149 case ui::AXEventGenerator::Event::ROW_COUNT_CHANGED:
150 case ui::AXEventGenerator::Event::SET_SIZE_CHANGED:
151 case ui::AXEventGenerator::Event::SORT_CHANGED:
152 case ui::AXEventGenerator::Event::STATE_CHANGED:
153 case ui::AXEventGenerator::Event::TEXT_ATTRIBUTE_CHANGED:
154 case ui::AXEventGenerator::Event::VALUE_MAX_CHANGED:
155 case ui::AXEventGenerator::Event::VALUE_MIN_CHANGED:
156 case ui::AXEventGenerator::Event::VALUE_STEP_CHANGED:
157 // Unhandled event type.
158 break;
159 }
160 }

References DispatchWinAccessibilityEvent(), event_type, flutter::AccessibilityBridge::GetFlutterPlatformNodeDelegateFromID(), GetFocusedNode(), node_delegate, and SetFocus().

## ◆ SetFocus()

void flutter::AccessibilityBridgeWindows::SetFocus | ( | std::shared_ptr< FlutterPlatformNodeDelegateWindows > | node_delegate | ) |
| virtual

Definition at line 181 of file accessibility_bridge_windows.cc.

182 {
183 node_delegate->SetFocus();
184 }

References node_delegate.

Referenced by OnAccessibilityEvent().

The documentation for this class was generated from the following files:

- shell/platform/windows/accessibility_bridge_windows.h
- shell/platform/windows/accessibility_bridge_windows.cc

flutter::FlutterWindowsEngine::DispatchSemanticsAction
bool DispatchSemanticsAction(uint64_t id, FlutterSemanticsAction action, fml::MallocMapping data)
Definition: flutter_windows_engine.cc:709
flutter::AccessibilityBridge::GetFlutterPlatformNodeDelegateFromID
std::weak_ptr< FlutterPlatformNodeDelegate > GetFlutterPlatformNodeDelegateFromID(AccessibilityNodeId id) const
Get the flutter platform node delegate with the given id from this accessibility bridge....
Definition: accessibility_bridge.cc:131
flutter::AccessibilityBridgeWindows::DispatchWinAccessibilityEvent
virtual void DispatchWinAccessibilityEvent(std::shared_ptr< FlutterPlatformNodeDelegateWindows > node_delegate, ax::mojom::Event event_type)
Definition: accessibility_bridge_windows.cc:175
flutter::AccessibilityBridge::GetAXTreeData
const ui::AXTreeData & GetAXTreeData() const
Get the ax tree data from this accessibility bridge. The tree data contains information such as the i...
Definition: accessibility_bridge.cc:141
flutter::AccessibilityBridgeWindows::SetFocus
virtual void SetFocus(std::shared_ptr< FlutterPlatformNodeDelegateWindows > node_delegate)
Definition: accessibility_bridge_windows.cc:181
flutter::AccessibilityBridgeWindows::GetFocusedNode
virtual std::weak_ptr< FlutterPlatformNodeDelegate > GetFocusedNode()
Definition: accessibility_bridge_windows.cc:206
action
int action
Definition: keyboard_key_handler_unittests.cc:116
flutter::AccessibilityBridge::RootDelegate
ui::AXPlatformNodeDelegate * RootDelegate() const override
Definition: accessibility_bridge.cc:721
event_type
ax::mojom::Event event_type
Definition: accessibility_bridge_windows_unittests.cc:33
flutter::FlutterWindowsView::GetEngine
FlutterWindowsEngine * GetEngine()
Definition: flutter_windows_view.cc:649
node_delegate
std::shared_ptr< FlutterPlatformNodeDelegateWindows > node_delegate
Definition: accessibility_bridge_windows_unittests.cc:32