Suppress blocked nodes from tree focus

Author: JSUYA

flutter/shell/platform/common/accessibility_bridge.cc

@@ -554,12 +554,15 @@ void AccessibilityBridge::SetTooltipFromFlutterUpdate(
 void AccessibilityBridge::SetTreeData(const SemanticsNode& node,
                                       ui::AXTreeUpdate& tree_update) {
   const FlutterSemanticsFlags* flags = node.flags;
+  const bool is_accessibility_focus_blocked =
+      flags->is_accessibility_focus_blocked;
   // Set selection of the focused node if:
   // 1. this text field has a valid selection
   // 2. this text field doesn't have a valid selection but had selection stored
   //    in the tree.
   if (flags->is_text_field &&
-      flags->is_focused == FlutterTristate::kFlutterTristateTrue) {
+      flags->is_focused == FlutterTristate::kFlutterTristateTrue &&
+      !is_accessibility_focus_blocked) {
     if (node.text_selection_base != -1) {
       tree_update.tree_data.sel_anchor_object_id = node.id;
       tree_update.tree_data.sel_anchor_offset = node.text_selection_base;
@@ -573,13 +576,21 @@ void AccessibilityBridge::SetTreeData(const SemanticsNode& node,
       tree_update.tree_data.sel_focus_offset = -1;
       tree_update.has_tree_data = true;
     }
+  } else if (tree_update.tree_data.sel_anchor_object_id == node.id) {
+    tree_update.tree_data.sel_anchor_object_id = ui::AXNode::kInvalidAXID;
+    tree_update.tree_data.sel_anchor_offset = -1;
+    tree_update.tree_data.sel_focus_object_id = ui::AXNode::kInvalidAXID;
+    tree_update.tree_data.sel_focus_offset = -1;
+    tree_update.has_tree_data = true;
   }
 
-  if (flags->is_focused == FlutterTristate::kFlutterTristateTrue &&
+  if (!is_accessibility_focus_blocked &&
+      flags->is_focused == FlutterTristate::kFlutterTristateTrue &&
       tree_update.tree_data.focus_id != node.id) {
     tree_update.tree_data.focus_id = node.id;
     tree_update.has_tree_data = true;
-  } else if (flags->is_focused != FlutterTristate::kFlutterTristateTrue &&
+  } else if ((is_accessibility_focus_blocked ||
+              flags->is_focused != FlutterTristate::kFlutterTristateTrue) &&
              tree_update.tree_data.focus_id == node.id) {
     tree_update.tree_data.focus_id = ui::AXNode::kInvalidAXID;
     tree_update.has_tree_data = true;

flutter/shell/platform/tizen/accessibility_bridge_unittests.cc

@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include <algorithm>
+
 #include "flutter/shell/platform/common/test_accessibility_bridge.h"
 
 #include "flutter/third_party/accessibility/ax/ax_action_data.h"
@@ -18,10 +20,11 @@ FlutterTransformation IdentityTransform() {
   };
 }
 
-FlutterSemanticsFlags MakeFlags(bool blocked) {
+FlutterSemanticsFlags MakeFlags(bool blocked, bool focused = false) {
   FlutterSemanticsFlags flags = {};
   flags.struct_size = sizeof(FlutterSemanticsFlags);
   flags.is_accessibility_focus_blocked = blocked;
+  flags.is_focused = focused ? kFlutterTristateTrue : kFlutterTristateFalse;
   return flags;
 }
 
@@ -111,6 +114,32 @@ TEST(AccessibilityBridgeTest, BlockedNodeRejectsAccessibilityFocusAction) {
   EXPECT_EQ(bridge.GetLastFocusedId(), ui::AXNode::kInvalidAXID);
 }
 
+TEST(AccessibilityBridgeTest, BlockedFocusedNodeDoesNotBecomeTreeFocus) {
+  TestAccessibilityBridge bridge;
+  auto flags = MakeFlags(true, true);
+  auto node = MakeNode(1, &flags);
+
+  bridge.AddFlutterSemanticsNodeUpdate(node);
+  bridge.CommitUpdates();
+
+  EXPECT_EQ(bridge.GetAXTreeData().focus_id, ui::AXNode::kInvalidAXID);
+  EXPECT_EQ(std::find(bridge.accessibility_events.begin(),
+                      bridge.accessibility_events.end(),
+                      ui::AXEventGenerator::Event::FOCUS_CHANGED),
+            bridge.accessibility_events.end());
+}
+
+TEST(AccessibilityBridgeTest, UnblockedFocusedNodeBecomesTreeFocus) {
+  TestAccessibilityBridge bridge;
+  auto flags = MakeFlags(false, true);
+  auto node = MakeNode(1, &flags);
+
+  bridge.AddFlutterSemanticsNodeUpdate(node);
+  bridge.CommitUpdates();
+
+  EXPECT_EQ(bridge.GetAXTreeData().focus_id, node.id);
+}
+
 TEST(AccessibilityBridgeTest, UnblockedNodeAcceptsAccessibilityFocusAction) {
   TestAccessibilityBridge bridge;
   auto flags = MakeFlags(false);

flutter/third_party/accessibility/ax/platform/ax_platform_node_auralinux.cc

@@ -4358,9 +4358,6 @@ AXPlatformNodeAuraLinux::HitTestSync(gint x, gint y, AtkCoordType coord_type) {
 }
 
 bool AXPlatformNodeAuraLinux::GrabFocus() {
-  if (!GetData().HasState(ax::mojom::State::kFocusable))
-    return false;
-
   AXActionData action_data;
   action_data.action = ax::mojom::Action::kFocus;
   return delegate_->AccessibilityPerformAction(action_data);
@@ -5064,17 +5061,13 @@ bool AXPlatformNodeAuraLinux::SetHighlighted(AtkObject* obj) {
     return false;
   }
 
-  if (!GetData().HasState(ax::mojom::State::kFocusable) || GetData().IsIgnored())
-    return false;
-
   InvalidateHighlighted();
 
   auto focused_obj = AXPlatformNodeAuraLinux::FromAtkObject(obj);
 
   if (focused_obj) {
     focused_obj->ScrollToNode(AXPlatformNodeBase::ScrollType::Anywhere);
-    if (!focused_obj->GrabFocus())
-      return false;
+    focused_obj->GrabFocus();
     g_current_focused = obj;
 
     atk_object_notify_state_change(g_current_focused, ATK_STATE_HIGHLIGHTED,