makes android semanticsnode to ignore hittest if it is not focusable (flutter#22205)

Author: chunhtai

shell/platform/android/io/flutter/view/AccessibilityBridge.java

@@ -207,6 +207,11 @@ public class AccessibilityBridge extends AccessibilityNodeProvider {
   // beneath a stylus or mouse cursor.
   @Nullable private SemanticsNode hoveredObject;
 
+  @VisibleForTesting
+  public int getHoveredObjectId() {
+    return hoveredObject.id;
+  }
+
   // A Java/Android cached representation of the Flutter app's navigation stack. The Flutter
   // navigation stack is tracked so that accessibility announcements can be made during Flutter's
   // navigation changes.
@@ -2180,7 +2185,7 @@ private SemanticsNode hitTest(float[] point) {
           return result;
         }
       }
-      return this;
+      return isFocusable() ? this : null;
     }
 
     // TODO(goderbauer): This should be decided by the framework once we have more information

shell/platform/android/test/io/flutter/view/AccessibilityBridgeTest.java

@@ -204,6 +204,70 @@ public void itAnnouncesRouteNameWhenAddingNewRoute() {
     assertEquals(sentences.get(0).toString(), "new_node2");
   }
 
+  @Test
+  public void itIgnoresUnfocusableNodeDuringHitTest() {
+    AccessibilityViewEmbedder mockViewEmbedder = mock(AccessibilityViewEmbedder.class);
+    AccessibilityManager mockManager = mock(AccessibilityManager.class);
+    View mockRootView = mock(View.class);
+    Context context = mock(Context.class);
+    when(mockRootView.getContext()).thenReturn(context);
+    when(context.getPackageName()).thenReturn("test");
+    AccessibilityBridge accessibilityBridge =
+        setUpBridge(mockRootView, mockManager, mockViewEmbedder);
+    ViewParent mockParent = mock(ViewParent.class);
+    when(mockRootView.getParent()).thenReturn(mockParent);
+    when(mockManager.isEnabled()).thenReturn(true);
+    when(mockManager.isTouchExplorationEnabled()).thenReturn(true);
+
+    TestSemanticsNode root = new TestSemanticsNode();
+    root.id = 0;
+    root.left = 0;
+    root.top = 0;
+    root.bottom = 20;
+    root.right = 20;
+    TestSemanticsNode ignored = new TestSemanticsNode();
+    ignored.id = 1;
+    ignored.addFlag(AccessibilityBridge.Flag.SCOPES_ROUTE);
+    ignored.left = 0;
+    ignored.top = 0;
+    ignored.bottom = 20;
+    ignored.right = 20;
+    root.children.add(ignored);
+    TestSemanticsNode child = new TestSemanticsNode();
+    child.id = 2;
+    child.label = "label";
+    child.left = 0;
+    child.top = 0;
+    child.bottom = 20;
+    child.right = 20;
+    root.children.add(child);
+    TestSemanticsUpdate testSemanticsUpdate = root.toUpdate();
+    accessibilityBridge.updateSemantics(testSemanticsUpdate.buffer, testSemanticsUpdate.strings);
+
+    ArgumentCaptor<AccessibilityEvent> eventCaptor =
+        ArgumentCaptor.forClass(AccessibilityEvent.class);
+    verify(mockParent, times(2))
+        .requestSendAccessibilityEvent(eq(mockRootView), eventCaptor.capture());
+    AccessibilityEvent event = eventCaptor.getAllValues().get(0);
+    assertEquals(event.getEventType(), AccessibilityEvent.TYPE_WINDOW_STATE_CHANGED);
+
+    // Synthesize an accessibility hit test event.
+    MotionEvent mockEvent = mock(MotionEvent.class);
+    when(mockEvent.getX()).thenReturn(10.0f);
+    when(mockEvent.getY()).thenReturn(10.0f);
+    when(mockEvent.getAction()).thenReturn(MotionEvent.ACTION_HOVER_ENTER);
+    boolean hit = accessibilityBridge.onAccessibilityHoverEvent(mockEvent);
+
+    assertEquals(hit, true);
+
+    eventCaptor = ArgumentCaptor.forClass(AccessibilityEvent.class);
+    verify(mockParent, times(3))
+        .requestSendAccessibilityEvent(eq(mockRootView), eventCaptor.capture());
+    event = eventCaptor.getAllValues().get(2);
+    assertEquals(event.getEventType(), AccessibilityEvent.TYPE_VIEW_HOVER_ENTER);
+    assertEquals(accessibilityBridge.getHoveredObjectId(), 2);
+  }
+
   @Test
   public void itAnnouncesRouteNameWhenRemoveARoute() {
     AccessibilityViewEmbedder mockViewEmbedder = mock(AccessibilityViewEmbedder.class);