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accessibility_bridge.h
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1 // Copyright 2013 The Flutter Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifndef SHELL_PLATFORM_IOS_FRAMEWORK_SOURCE_ACCESSIBILITY_BRIDGE_H_
6 #define SHELL_PLATFORM_IOS_FRAMEWORK_SOURCE_ACCESSIBILITY_BRIDGE_H_
7 
8 #import <UIKit/UIKit.h>
9 
10 #include <memory>
11 #include <unordered_map>
12 #include <unordered_set>
13 #include <vector>
14 
15 #include "flutter/fml/macros.h"
16 #include "flutter/fml/memory/weak_ptr.h"
17 #include "flutter/fml/platform/darwin/scoped_nsobject.h"
18 #include "flutter/lib/ui/semantics/custom_accessibility_action.h"
19 #include "flutter/lib/ui/semantics/semantics_node.h"
20 #import "flutter/shell/platform/darwin/common/framework/Headers/FlutterChannels.h"
21 #import "flutter/shell/platform/darwin/ios/framework/Source/FlutterTextInputPlugin.h"
22 #import "flutter/shell/platform/darwin/ios/framework/Source/FlutterView.h"
23 #import "flutter/shell/platform/darwin/ios/framework/Source/FlutterViewController_Internal.h"
24 #import "flutter/shell/platform/darwin/ios/framework/Source/SemanticsObject.h"
25 #import "flutter/shell/platform/darwin/ios/framework/Source/accessibility_bridge_ios.h"
26 #include "third_party/skia/include/core/SkRect.h"
27 
28 namespace flutter {
29 class PlatformViewIOS;
30 
31 /**
32  * An accessibility instance is bound to one `FlutterViewController` and
33  * `FlutterView` instance.
34  *
35  * It helps populate the UIView's accessibilityElements property from Flutter's
36  * semantics nodes.
37  */
38 class AccessibilityBridge final : public AccessibilityBridgeIos {
39  public:
40  /** Delegate for handling iOS operations. */
41  class IosDelegate {
42  public:
43  virtual ~IosDelegate() = default;
44  /// Returns true when the FlutterViewController associated with the `view`
45  /// is presenting a modal view controller.
47  FlutterViewController* view_controller) = 0;
48  virtual void PostAccessibilityNotification(UIAccessibilityNotifications notification,
49  id argument) = 0;
50  };
51 
54  std::shared_ptr<FlutterPlatformViewsController> platform_views_controller,
55  std::unique_ptr<IosDelegate> ios_delegate = nullptr);
57 
60  void DispatchSemanticsAction(int32_t id, flutter::SemanticsAction action) override;
61  void DispatchSemanticsAction(int32_t id,
63  fml::MallocMapping args) override;
64  void AccessibilityObjectDidBecomeFocused(int32_t id) override;
65  void AccessibilityObjectDidLoseFocus(int32_t id) override;
66 
67  UIView<UITextInput>* textInputView() override;
68 
69  UIView* view() const override { return view_controller_.view; }
70 
71  bool isVoiceOverRunning() const override { return view_controller_.isVoiceOverRunning; }
72 
74 
75  std::shared_ptr<FlutterPlatformViewsController> GetPlatformViewsController() const override {
76  return platform_views_controller_;
77  };
78 
79  void clearState();
80 
81  private:
82  SemanticsObject* GetOrCreateObject(int32_t id, flutter::SemanticsNodeUpdates& updates);
83  SemanticsObject* FindNextFocusableIfNecessary();
84  // Finds the first focusable SemanticsObject rooted at the parent. This includes the parent itself
85  // if it is a focusable SemanticsObject.
86  //
87  // If the parent is nil, this function use the root SemanticsObject as the parent.
88  SemanticsObject* FindFirstFocusable(SemanticsObject* parent);
89  void VisitObjectsRecursivelyAndRemove(SemanticsObject* object,
90  NSMutableArray<NSNumber*>* doomed_uids);
91  void HandleEvent(NSDictionary<NSString*, id>* annotatedEvent);
92 
93  FlutterViewController* view_controller_;
94  PlatformViewIOS* platform_view_;
95  const std::shared_ptr<FlutterPlatformViewsController> platform_views_controller_;
96  // If the this id is kSemanticObjectIdInvalid, it means either nothing has
97  // been focused or the focus is currently outside of the flutter application
98  // (i.e. the status bar or keyboard)
99  int32_t last_focused_semantics_object_id_;
103  int32_t previous_route_id_;
104  std::unordered_map<int32_t, flutter::CustomAccessibilityAction> actions_;
105  std::vector<int32_t> previous_routes_;
106  std::unique_ptr<IosDelegate> ios_delegate_;
107 
109 };
110 
111 } // namespace flutter
112 
113 #endif // SHELL_PLATFORM_IOS_FRAMEWORK_SOURCE_ACCESSIBILITY_BRIDGE_H_
G_BEGIN_DECLS FlValue * args
std::unique_ptr< flutter::PlatformViewIOS > platform_view
void DispatchSemanticsAction(int32_t id, flutter::SemanticsAction action) override
void AccessibilityObjectDidBecomeFocused(int32_t id) override
std::unordered_map< int32_t, SemanticsNode > SemanticsNodeUpdates
fml::WeakPtr< AccessibilityBridge > GetWeakPtr()
AccessibilityBridge(std::unique_ptr< AccessibilityBridgeDelegate > delegate)
Creates a new instance of a accessibility bridge.
std::shared_ptr< FlutterPlatformViewsController > GetPlatformViewsController() const override
void AccessibilityObjectDidLoseFocus(int32_t id) override
SemanticsAction action
void UpdateSemantics(flutter::SemanticsNodeUpdates nodes, flutter::CustomAccessibilityActionUpdates actions)
A Mapping like NonOwnedMapping, but uses Free as its release proc.
Definition: mapping.h:129
UIView * view() const override
std::unordered_map< int32_t, CustomAccessibilityAction > CustomAccessibilityActionUpdates
UIView< UITextInput > * textInputView() override
#define FML_DISALLOW_COPY_AND_ASSIGN(TypeName)
Definition: macros.h:27
bool isVoiceOverRunning() const override
virtual void PostAccessibilityNotification(UIAccessibilityNotifications notification, id argument)=0
virtual bool IsFlutterViewControllerPresentingModalViewController(FlutterViewController *view_controller)=0