#include <flutter_platform_node_delegate.h>

Inheritance diagram for flutter::FlutterPlatformNodeDelegate:

Classes
class	OwnerBridge

Public Member Functions
	FlutterPlatformNodeDelegate ()

virtual	~FlutterPlatformNodeDelegate () override

const ui::AXUniqueId &	GetUniqueId () const override

const ui::AXNodeData &	GetData () const override

bool	AccessibilityPerformAction (const ui::AXActionData &data) override

gfx::NativeViewAccessible	GetParent () override

gfx::NativeViewAccessible	GetFocus () override

int	GetChildCount () const override

gfx::NativeViewAccessible	ChildAtIndex (int index) override

gfx::Rect	GetBoundsRect (const ui::AXCoordinateSystem coordinate_system, const ui::AXClippingBehavior clipping_behavior, ui::AXOffscreenResult *offscreen_result) const override

gfx::NativeViewAccessible	GetLowestPlatformAncestor () const override

ui::AXNodePosition::AXPositionInstance	CreateTextPositionAt (int offset) const override

virtual void	Init (std::weak_ptr< OwnerBridge > bridge, ui::AXNode *node)
	Called only once, immediately after construction. The constructor doesn't take any arguments because in the Windows subclass we use a special function to construct a COM object. Subclasses must call super. More...

ui::AXNode *	GetAXNode () const
	Gets the underlying ax node for this platform node delegate. More...

std::weak_ptr< OwnerBridge >	GetOwnerBridge () const
	Gets the owner of this platform node delegate. This is useful when you want to get the information about surrounding nodes of this platform node delegate, e.g. the global rect of this platform node delegate. This pointer is only safe in the platform thread. More...

virtual ui::AXPlatformNode *	GetPlatformNode () const

virtual ui::AXPlatformNode *	GetFromNodeID (int32_t id) override

virtual ui::AXPlatformNode *	GetFromTreeIDAndNodeID (const ui::AXTreeID &tree_id, int32_t node_id) override

virtual const ui::AXTree::Selection	GetUnignoredSelection () const override

Detailed Description

The platform node delegate to be used in accessibility bridge. This class is responsible for providing native accessibility object with appropriate information, such as accessibility label/value/bounds.

While most methods have default implementations and are ready to be used as-is, the subclasses must override the GetNativeViewAccessible to return native accessibility objects. To do that, subclasses should create and maintain AXPlatformNode[s] which delegate their accessibility attributes to this class.

For desktop platforms, subclasses also need to override the GetBoundsRect to apply window-to-screen transform.

This class transforms bounds assuming the device pixel ratio is 1.0. See the https://github.com/flutter/flutter/issues/74283 for more information.

Definition at line 33 of file flutter_platform_node_delegate.h.

Constructor & Destructor Documentation

◆ FlutterPlatformNodeDelegate()

flutter::FlutterPlatformNodeDelegate::FlutterPlatformNodeDelegate ( )

default

◆ ~FlutterPlatformNodeDelegate()

flutter::FlutterPlatformNodeDelegate::~FlutterPlatformNodeDelegate ( )

overridevirtualdefault

Member Function Documentation

◆ AccessibilityPerformAction()

bool flutter::FlutterPlatformNodeDelegate::AccessibilityPerformAction ( const ui::AXActionData & data )

override

Definition at line 30 of file flutter_platform_node_delegate.cc.

                                 {
   AccessibilityNodeId target = ax_node_->id();
   auto bridge_ptr = bridge_.lock();
   BASE_DCHECK(bridge_ptr);
   switch (data.action) {
     case ax::mojom::Action::kDoDefault:
       bridge_ptr->DispatchAccessibilityAction(
           target, FlutterSemanticsAction::kFlutterSemanticsActionTap, {});
       return true;
     case ax::mojom::Action::kFocus:
       bridge_ptr->SetLastFocusedId(target);
       bridge_ptr->DispatchAccessibilityAction(
           target,
           FlutterSemanticsAction::
               kFlutterSemanticsActionDidGainAccessibilityFocus,
           {});
       return true;
     case ax::mojom::Action::kScrollToMakeVisible:
       bridge_ptr->DispatchAccessibilityAction(
           target, FlutterSemanticsAction::kFlutterSemanticsActionShowOnScreen,
           {});
       return true;
     // TODO(chunhtai): support more actions.
     default:
       return false;
   }
   return false;
 }

◆ ChildAtIndex()

gfx::NativeViewAccessible flutter::FlutterPlatformNodeDelegate::ChildAtIndex ( int index )

override

Definition at line 87 of file flutter_platform_node_delegate.cc.

                                                                            {
   auto bridge_ptr = bridge_.lock();
   BASE_DCHECK(bridge_ptr);
   AccessibilityNodeId child = ax_node_->GetUnignoredChildAtIndex(index)->id();
   return bridge_ptr->GetNativeAccessibleFromId(child);
 }

◆ CreateTextPositionAt()

ui::AXNodePosition::AXPositionInstance flutter::FlutterPlatformNodeDelegate::CreateTextPositionAt ( int offset ) const

override

Definition at line 136 of file flutter_platform_node_delegate.cc.

                                                                   {
   return ui::AXNodePosition::CreatePosition(*ax_node_, offset);
 }

◆ GetAXNode()

ui::AXNode * flutter::FlutterPlatformNodeDelegate::GetAXNode ( ) const

Gets the underlying ax node for this platform node delegate.

Definition at line 26 of file flutter_platform_node_delegate.cc.

                                                        {
   return ax_node_;
 }

◆ GetBoundsRect()

gfx::Rect flutter::FlutterPlatformNodeDelegate::GetBoundsRect	(	const ui::AXCoordinateSystem	coordinate_system,
		const ui::AXClippingBehavior	clipping_behavior,
		ui::AXOffscreenResult *	offscreen_result
	)		const

override

Definition at line 94 of file flutter_platform_node_delegate.cc.

                                                  {
   auto bridge_ptr = bridge_.lock();
   BASE_DCHECK(bridge_ptr);
   // TODO(chunhtai): We need to apply screen dpr in here.
   // https://github.com/flutter/flutter/issues/74283
   const bool clip_bounds =
       clipping_behavior == ui::AXClippingBehavior::kClipped;
   bool offscreen = false;
   gfx::RectF bounds =
       bridge_ptr->RelativeToGlobalBounds(ax_node_, offscreen, clip_bounds);
   if (offscreen_result != nullptr) {
     *offscreen_result = offscreen ? ui::AXOffscreenResult::kOffscreen
                                   : ui::AXOffscreenResult::kOnscreen;
   }
   return gfx::ToEnclosingRect(bounds);
 }

◆ GetChildCount()

int flutter::FlutterPlatformNodeDelegate::GetChildCount ( ) const

override

Definition at line 83 of file flutter_platform_node_delegate.cc.

                                                      {
   return static_cast<int>(ax_node_->GetUnignoredChildCount());
 }

◆ GetData()

const ui::AXNodeData & flutter::FlutterPlatformNodeDelegate::GetData ( ) const

override

Definition at line 60 of file flutter_platform_node_delegate.cc.

                                                                {
   return ax_node_->data();
 }

◆ GetFocus()

gfx::NativeViewAccessible flutter::FlutterPlatformNodeDelegate::GetFocus ( )

override

Definition at line 73 of file flutter_platform_node_delegate.cc.

                                                               {
   auto bridge_ptr = bridge_.lock();
   BASE_DCHECK(bridge_ptr);
   AccessibilityNodeId last_focused = bridge_ptr->GetLastFocusedId();
   if (last_focused == ui::AXNode::kInvalidAXID) {
     return nullptr;
   }
   return bridge_ptr->GetNativeAccessibleFromId(last_focused);
 }

◆ GetFromNodeID()

ui::AXPlatformNode * flutter::FlutterPlatformNodeDelegate::GetFromNodeID ( int32_t id )

overridevirtual

Definition at line 140 of file flutter_platform_node_delegate.cc.

                      {
   ui::AXTreeManager* tree_manager =
       ui::AXTreeManagerMap::GetInstance().GetManager(
           ax_node_->tree()->GetAXTreeID());
   AccessibilityBridge* platform_manager =
       static_cast<AccessibilityBridge*>(tree_manager);
   return platform_manager->GetPlatformNodeFromTree(node_id);
 }

References flutter::AccessibilityBridge::GetPlatformNodeFromTree().

◆ GetFromTreeIDAndNodeID()

ui::AXPlatformNode * flutter::FlutterPlatformNodeDelegate::GetFromTreeIDAndNodeID	(	const ui::AXTreeID &	tree_id,
		int32_t	node_id
	)

overridevirtual

Definition at line 150 of file flutter_platform_node_delegate.cc.

                      {
   ui::AXTreeManager* tree_manager =
       ui::AXTreeManagerMap::GetInstance().GetManager(tree_id);
   AccessibilityBridge* platform_manager =
       static_cast<AccessibilityBridge*>(tree_manager);
   return platform_manager->GetPlatformNodeFromTree(node_id);
 }

References flutter::AccessibilityBridge::GetPlatformNodeFromTree().

◆ GetLowestPlatformAncestor()

gfx::NativeViewAccessible flutter::FlutterPlatformNodeDelegate::GetLowestPlatformAncestor ( ) const

override

Definition at line 124 of file flutter_platform_node_delegate.cc.

                                                              {
   auto bridge_ptr = bridge_.lock();
   BASE_DCHECK(bridge_ptr);
   auto lowest_platform_ancestor = ax_node_->GetLowestPlatformAncestor();
   if (lowest_platform_ancestor) {
     return bridge_ptr->GetNativeAccessibleFromId(
         ax_node_->GetLowestPlatformAncestor()->id());
   }
   return nullptr;
 }

◆ GetOwnerBridge()

std::weak_ptr< FlutterPlatformNodeDelegate::OwnerBridge > flutter::FlutterPlatformNodeDelegate::GetOwnerBridge ( ) const

Gets the owner of this platform node delegate. This is useful when you want to get the information about surrounding nodes of this platform node delegate, e.g. the global rect of this platform node delegate. This pointer is only safe in the platform thread.

Definition at line 115 of file flutter_platform_node_delegate.cc.

                                                   {
   return bridge_;
 }

◆ GetParent()

gfx::NativeViewAccessible flutter::FlutterPlatformNodeDelegate::GetParent ( )

override

Definition at line 64 of file flutter_platform_node_delegate.cc.

                                                                {
   if (!ax_node_->parent()) {
     return nullptr;
   }
   auto bridge_ptr = bridge_.lock();
   BASE_DCHECK(bridge_ptr);
   return bridge_ptr->GetNativeAccessibleFromId(ax_node_->parent()->id());
 }

◆ GetPlatformNode()

ui::AXPlatformNode * flutter::FlutterPlatformNodeDelegate::GetPlatformNode ( ) const

virtual

Definition at line 119 of file flutter_platform_node_delegate.cc.

                                                                      {
   return nullptr;
 }

◆ GetUnignoredSelection()

const ui::AXTree::Selection flutter::FlutterPlatformNodeDelegate::GetUnignoredSelection ( ) const

overridevirtual

Definition at line 160 of file flutter_platform_node_delegate.cc.

           {
   return ax_node_->GetUnignoredSelection();
 }

◆ GetUniqueId()

const ui::AXUniqueId& flutter::FlutterPlatformNodeDelegate::GetUniqueId ( ) const

inlineoverride

Definition at line 102 of file flutter_platform_node_delegate.h.

102 { return unique_id_; }

◆ Init()

void flutter::FlutterPlatformNodeDelegate::Init	(	std::weak_ptr< OwnerBridge >	bridge,
		ui::AXNode *	node
	)

virtual

Called only once, immediately after construction. The constructor doesn't take any arguments because in the Windows subclass we use a special function to construct a COM object. Subclasses must call super.

Definition at line 20 of file flutter_platform_node_delegate.cc.

                                                        {
   bridge_ = std::move(bridge);
   ax_node_ = node;
 }

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

shell/platform/common/flutter_platform_node_delegate.h
shell/platform/common/flutter_platform_node_delegate.cc

Classes

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ FlutterPlatformNodeDelegate()

◆ ~FlutterPlatformNodeDelegate()

Member Function Documentation

◆ AccessibilityPerformAction()

◆ ChildAtIndex()

◆ CreateTextPositionAt()

◆ GetAXNode()

◆ GetBoundsRect()

◆ GetChildCount()

◆ GetData()

◆ GetFocus()

◆ GetFromNodeID()

◆ GetFromTreeIDAndNodeID()

◆ GetLowestPlatformAncestor()

◆ GetOwnerBridge()

◆ GetParent()

◆ GetPlatformNode()

◆ GetUnignoredSelection()

◆ GetUniqueId()

◆ Init()