Wires up accessibility bridge in mac embedding

ci/licenses_golden/licenses_flutter

@@ -1098,6 +1098,8 @@ FILE: ../../../flutter/shell/platform/darwin/macos/framework/Headers/FlutterPlug
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Headers/FlutterPluginRegistrarMacOS.h
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Headers/FlutterViewController.h
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Info.plist
+FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/AccessibilityBridgeMacDelegate.h
+FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/AccessibilityBridgeMacDelegate.mm
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterAppDelegate.mm
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterBackingStore.h
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterBackingStore.mm
@@ -1132,6 +1134,9 @@ FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterMouse
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterOpenGLRenderer.h
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterOpenGLRenderer.mm
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterOpenGLRendererTest.mm
+FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterPlatformNodeDelegateMac.h
+FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterPlatformNodeDelegateMac.mm
+FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterPlatformNodeDelegateMacTest.mm
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterRenderer.h
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterRenderingBackend.h
 FILE: ../../../flutter/shell/platform/darwin/macos/framework/Source/FlutterRenderingBackend.mm

shell/platform/common/accessibility_bridge.cc

@@ -104,6 +104,13 @@ const ui::AXTreeData& AccessibilityBridge::GetAXTreeData() const {
   return tree_.data();
 }
 
+const std::vector<ui::AXEventGenerator::TargetedEvent>
+AccessibilityBridge::GetPendingEvents() {
+  std::vector<ui::AXEventGenerator::TargetedEvent> result(
+      event_generator_.begin(), event_generator_.end());
+  return result;
+}
+
 void AccessibilityBridge::OnNodeWillBeDeleted(ui::AXTree* tree,
                                               ui::AXNode* node) {}
 

shell/platform/common/accessibility_bridge.h

@@ -86,9 +86,10 @@ class AccessibilityBridge
     /// @param[in]  action              The generated flutter semantics action.
     /// @param[in]  data                Additional data associated with the
     ///                                 action.
-    virtual void DispatchAccessibilityAction(AccessibilityNodeId target,
-                                             FlutterSemanticsAction action,
-                                             std::vector<uint8_t> data) = 0;
+    virtual void DispatchAccessibilityAction(
+        AccessibilityNodeId target,
+        FlutterSemanticsAction action,
+        const std::vector<uint8_t>& data) = 0;
 
     //---------------------------------------------------------------------------
     /// @brief      Creates a platform specific FlutterPlatformNodeDelegate.
@@ -154,6 +155,14 @@ class AccessibilityBridge
   ///             has the keyboard focus or the text selection range.
   const ui::AXTreeData& GetAXTreeData() const;
 
+  //------------------------------------------------------------------------------
+  /// @brief      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.
+  const std::vector<ui::AXEventGenerator::TargetedEvent> GetPendingEvents();
+
  private:
   // See FlutterSemanticsNode in embedder.h
   typedef struct {

shell/platform/common/flutter_platform_node_delegate.h

@@ -37,7 +37,7 @@ class FlutterPlatformNodeDelegate : public ui::AXPlatformNodeDelegateBase {
   /// delegate.
   class OwnerBridge {
    public:
-    ~OwnerBridge() = default;
+    virtual ~OwnerBridge() = default;
 
    protected:
     friend class FlutterPlatformNodeDelegate;
@@ -96,7 +96,7 @@ class FlutterPlatformNodeDelegate : public ui::AXPlatformNodeDelegateBase {
   FlutterPlatformNodeDelegate();
 
   // |ui::AXPlatformNodeDelegateBase|
-  ~FlutterPlatformNodeDelegate() override;
+  virtual ~FlutterPlatformNodeDelegate() override;
 
   // |ui::AXPlatformNodeDelegateBase|
   const ui::AXNodeData& GetData() const override;

shell/platform/common/test_accessibility_bridge.cc

@@ -19,7 +19,7 @@ void TestAccessibilityBridgeDelegate::OnAccessibilityEvent(
 void TestAccessibilityBridgeDelegate::DispatchAccessibilityAction(
     AccessibilityNodeId target,
     FlutterSemanticsAction action,
-    std::vector<uint8_t> data) {
+    const std::vector<uint8_t>& data) {
   performed_actions.push_back(action);
 }
 

shell/platform/common/test_accessibility_bridge.h

@@ -18,7 +18,7 @@ class TestAccessibilityBridgeDelegate
       ui::AXEventGenerator::TargetedEvent targeted_event) override;
   void DispatchAccessibilityAction(AccessibilityNodeId target,
                                    FlutterSemanticsAction action,
-                                   std::vector<uint8_t> data) override;
+                                   const std::vector<uint8_t>& data) override;
   std::unique_ptr<FlutterPlatformNodeDelegate>
   CreateFlutterPlatformNodeDelegate();
 

shell/platform/darwin/macos/BUILD.gn

@@ -52,6 +52,8 @@ source_set("flutter_framework_source") {
   visibility = [ ":*" ]
 
   sources = [
+    "framework/Source/AccessibilityBridgeMacDelegate.h",
+    "framework/Source/AccessibilityBridgeMacDelegate.mm",
     "framework/Source/FlutterAppDelegate.mm",
     "framework/Source/FlutterBackingStore.h",
     "framework/Source/FlutterBackingStore.mm",
@@ -81,6 +83,8 @@ source_set("flutter_framework_source") {
     "framework/Source/FlutterMouseCursorPlugin.mm",
     "framework/Source/FlutterOpenGLRenderer.h",
     "framework/Source/FlutterOpenGLRenderer.mm",
+    "framework/Source/FlutterPlatformNodeDelegateMac.h",
+    "framework/Source/FlutterPlatformNodeDelegateMac.mm",
     "framework/Source/FlutterRenderer.h",
     "framework/Source/FlutterRenderingBackend.h",
     "framework/Source/FlutterRenderingBackend.mm",
@@ -108,6 +112,7 @@ source_set("flutter_framework_source") {
     ":macos_gpu_configuration",
     "//flutter/flow:flow",
     "//flutter/fml",
+    "//flutter/shell/platform/common:common_cpp_accessibility",
     "//flutter/shell/platform/common:common_cpp_input",
     "//flutter/shell/platform/common:common_cpp_switches",
     "//flutter/shell/platform/darwin/common:framework_shared",
@@ -159,6 +164,7 @@ executable("flutter_desktop_darwin_unittests") {
     "framework/Source/FlutterMetalRendererTest.mm",
     "framework/Source/FlutterMetalSurfaceManagerTest.mm",
     "framework/Source/FlutterOpenGLRendererTest.mm",
+    "framework/Source/FlutterPlatformNodeDelegateMacTest.mm",
     "framework/Source/FlutterViewControllerTest.mm",
     "framework/Source/FlutterViewControllerTestUtils.h",
     "framework/Source/FlutterViewControllerTestUtils.mm",
@@ -171,6 +177,7 @@ executable("flutter_desktop_darwin_unittests") {
   deps = [
     ":flutter_desktop_darwin_fixtures",
     ":flutter_framework_source",
+    "//flutter/shell/platform/common:common_cpp_accessibility",
     "//flutter/shell/platform/darwin/common:framework_shared",
     "//flutter/shell/platform/darwin/graphics",
     "//flutter/shell/platform/embedder:embedder_as_internal_library",

shell/platform/darwin/macos/framework/Source/AccessibilityBridgeMacDelegate.h

@@ -0,0 +1,83 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef FLUTTER_SHELL_PLATFORM_DARWIN_MACOS_FRAMEWORK_SOURCE_ACCESSIBILITYBRIDGEMACDELEGATE_H_
+#define FLUTTER_SHELL_PLATFORM_DARWIN_MACOS_FRAMEWORK_SOURCE_ACCESSIBILITYBRIDGEMACDELEGATE_H_
+
+#import <Cocoa/Cocoa.h>
+
+#include "flutter/shell/platform/common/accessibility_bridge.h"
+
+@class FlutterEngine;
+
+namespace flutter {
+
+//------------------------------------------------------------------------------
+/// The macOS implementation of AccessibilityBridge::AccessibilityBridgeDelegate.
+/// This delegate is used to create AccessibilityBridge in the macOS embedding.
+class AccessibilityBridgeMacDelegate : public AccessibilityBridge::AccessibilityBridgeDelegate {
+ public:
+  //---------------------------------------------------------------------------
+  /// @brief      Creates an AccessibilityBridgeMacDelegate.
+  /// @param[in]  flutterEngine     The weak reference to the FlutterEngine.
+  explicit AccessibilityBridgeMacDelegate(__weak FlutterEngine* flutter_engine);
+  virtual ~AccessibilityBridgeMacDelegate() = default;
+
+  // |AccessibilityBridge::AccessibilityBridgeDelegate|
+  void OnAccessibilityEvent(ui::AXEventGenerator::TargetedEvent targeted_event) override;
+
+  // |AccessibilityBridge::AccessibilityBridgeDelegate|
+  void DispatchAccessibilityAction(AccessibilityNodeId target,
+                                   FlutterSemanticsAction action,
+                                   const std::vector<uint8_t>& data) override;
+
+  // |AccessibilityBridge::AccessibilityBridgeDelegate|
+  std::unique_ptr<FlutterPlatformNodeDelegate> CreateFlutterPlatformNodeDelegate() override;
+
+ private:
+  /// A wrapper structure to wraps macOS native accessibility events.
+  struct NSAccessibilityEvent {
+    NSAccessibilityNotificationName name;
+    gfx::NativeViewAccessible target;
+    NSDictionary* user_info;
+  };
+
+  //---------------------------------------------------------------------------
+  /// @brief      Posts the given event against the given node to the macOS
+  ///             accessibility notification system.
+  /// @param[in]  native_node       The event target, must not be nil.
+  /// @param[in]  mac_notification  The event name, must not be nil.
+  void DispatchMacOSNotification(gfx::NativeViewAccessible native_node,
+                                 NSAccessibilityNotificationName mac_notification);
+
+  //---------------------------------------------------------------------------
+  /// @brief      Posts the given event against the given node with the
+  ///             additional attributes to the macOS accessibility notification
+  ///             system.
+  /// @param[in]  native_node       The event target, must not be nil.
+  /// @param[in]  mac_notification  The event name, must not be nil.
+  /// @param[in]  user_info         The additional attributes, must not be nil.
+  void DispatchMacOSNotificationWithUserInfo(gfx::NativeViewAccessible native_node,
+                                             NSAccessibilityNotificationName mac_notification,
+                                             NSDictionary* user_info);
+
+  //---------------------------------------------------------------------------
+  /// @brief      Whether the given event is in current pending events.
+  /// @param[in]  event_type        The event you would like to look up.
+  bool HasPendingEvent(ui::AXEventGenerator::Event event) const;
+
+  //---------------------------------------------------------------------------
+  /// @brief      Converts the give ui::AXEventGenerator::Event into
+  ///             macOS native accessibility event[s]
+  /// @param[in]  event_type        The original event type.
+  /// @param[in]  ax_node           The original event target.
+  std::vector<NSAccessibilityEvent> MacOSEventsFromAXEvent(ui::AXEventGenerator::Event event_type,
+                                                           const ui::AXNode& ax_node) const;
+
+  __weak FlutterEngine* flutter_engine_;
+};
+
+}  // namespace flutter
+
+#endif  // FLUTTER_SHELL_PLATFORM_DARWIN_MACOS_FRAMEWORK_SOURCE_ACCESSIBILITYBRIDGEMACDELEGATE_H_