Allow TalkBack navigation while a platform view is rendered (#21719)
diff --git a/shell/platform/android/io/flutter/view/AccessibilityBridge.java b/shell/platform/android/io/flutter/view/AccessibilityBridge.java
index cd50894..92cbe68 100644
--- a/shell/platform/android/io/flutter/view/AccessibilityBridge.java
+++ b/shell/platform/android/io/flutter/view/AccessibilityBridge.java
@@ -28,6 +28,7 @@
import androidx.annotation.VisibleForTesting;
import io.flutter.BuildConfig;
import io.flutter.Log;
+import io.flutter.embedding.android.FlutterActivity;
import io.flutter.embedding.engine.systemchannels.AccessibilityChannel;
import io.flutter.plugin.platform.PlatformViewsAccessibilityDelegate;
import io.flutter.util.Predicate;
@@ -541,12 +542,22 @@
return null;
}
+ // Generate accessibility node for platform views using a virtual display.
+ //
+ // In this case, register the accessibility node in the view embedder,
+ // so the accessibility tree can be mirrored as a subtree of the Flutter accessibility tree.
+ // This is in constrast to hybrid composition where the embeded view is in the view hiearchy,
+ // so it doesn't need to be mirrored.
+ //
+ // See the case down below for how hybrid composition is handled.
if (semanticsNode.platformViewId != -1) {
- // For platform views we delegate the node creation to the accessibility view embedder.
View embeddedView =
platformViewsAccessibilityDelegate.getPlatformViewById(semanticsNode.platformViewId);
- Rect bounds = semanticsNode.getGlobalRect();
- return accessibilityViewEmbedder.getRootNode(embeddedView, semanticsNode.id, bounds);
+ boolean childUsesVirtualDisplay = !(embeddedView.getContext() instanceof FlutterActivity);
+ if (childUsesVirtualDisplay) {
+ Rect bounds = semanticsNode.getGlobalRect();
+ return accessibilityViewEmbedder.getRootNode(embeddedView, semanticsNode.id, bounds);
+ }
}
AccessibilityNodeInfo result =
@@ -823,11 +834,28 @@
}
for (SemanticsNode child : semanticsNode.childrenInTraversalOrder) {
- if (!child.hasFlag(Flag.IS_HIDDEN)) {
- result.addChild(rootAccessibilityView, child.id);
+ if (child.hasFlag(Flag.IS_HIDDEN)) {
+ continue;
}
- }
+ if (child.platformViewId != -1) {
+ View embeddedView =
+ platformViewsAccessibilityDelegate.getPlatformViewById(child.platformViewId);
+ // Add the embeded view as a child of the current accessibility node if it's using
+ // hybrid composition.
+ //
+ // In this case, the view is in the Activity's view hierarchy, so it doesn't need to be
+ // mirrored.
+ //
+ // See the case above for how virtual displays are handled.
+ boolean childUsesHybridComposition = embeddedView.getContext() instanceof FlutterActivity;
+ if (childUsesHybridComposition) {
+ result.addChild(embeddedView);
+ continue;
+ }
+ }
+ result.addChild(rootAccessibilityView, child.id);
+ }
return result;
}
diff --git a/shell/platform/android/test/io/flutter/view/AccessibilityBridgeTest.java b/shell/platform/android/test/io/flutter/view/AccessibilityBridgeTest.java
index 81d87ae..673c1e4 100644
--- a/shell/platform/android/test/io/flutter/view/AccessibilityBridgeTest.java
+++ b/shell/platform/android/test/io/flutter/view/AccessibilityBridgeTest.java
@@ -5,6 +5,7 @@
package io.flutter.view;
import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
import static org.mockito.Matchers.eq;
import static org.mockito.Mockito.any;
import static org.mockito.Mockito.anyInt;
@@ -16,14 +17,17 @@
import static org.mockito.Mockito.when;
import android.annotation.TargetApi;
+import android.app.Activity;
import android.content.ContentResolver;
import android.content.Context;
+import android.graphics.Rect;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewParent;
import android.view.accessibility.AccessibilityEvent;
import android.view.accessibility.AccessibilityManager;
import android.view.accessibility.AccessibilityNodeInfo;
+import io.flutter.embedding.android.FlutterActivity;
import io.flutter.embedding.engine.systemchannels.AccessibilityChannel;
import io.flutter.plugin.platform.PlatformViewsAccessibilityDelegate;
import java.nio.ByteBuffer;
@@ -33,6 +37,7 @@
import org.junit.runner.RunWith;
import org.mockito.ArgumentCaptor;
import org.robolectric.RobolectricTestRunner;
+import org.robolectric.RuntimeEnvironment;
import org.robolectric.annotation.Config;
@Config(manifest = Config.NONE)
@@ -199,6 +204,81 @@
}
@Test
+ public void itProducesPlatformViewNodeForHybridComposition() {
+ PlatformViewsAccessibilityDelegate accessibilityDelegate =
+ mock(PlatformViewsAccessibilityDelegate.class);
+
+ Context context = RuntimeEnvironment.application.getApplicationContext();
+ View rootAccessibilityView = new View(context);
+ AccessibilityViewEmbedder accessibilityViewEmbedder = mock(AccessibilityViewEmbedder.class);
+ AccessibilityBridge accessibilityBridge =
+ setUpBridge(
+ rootAccessibilityView,
+ /*accessibilityChannel=*/ null,
+ /*accessibilityManager=*/ null,
+ /*contentResolver=*/ null,
+ accessibilityViewEmbedder,
+ accessibilityDelegate);
+
+ TestSemanticsNode root = new TestSemanticsNode();
+ root.id = 0;
+
+ TestSemanticsNode platformView = new TestSemanticsNode();
+ platformView.id = 1;
+ platformView.platformViewId = 1;
+ root.addChild(platformView);
+
+ TestSemanticsUpdate testSemanticsRootUpdate = root.toUpdate();
+ accessibilityBridge.updateSemantics(
+ testSemanticsRootUpdate.buffer, testSemanticsRootUpdate.strings);
+
+ TestSemanticsUpdate testSemanticsPlatformViewUpdate = platformView.toUpdate();
+ accessibilityBridge.updateSemantics(
+ testSemanticsPlatformViewUpdate.buffer, testSemanticsPlatformViewUpdate.strings);
+
+ View embeddedView = mock(View.class);
+ when(accessibilityDelegate.getPlatformViewById(1)).thenReturn(embeddedView);
+
+ when(embeddedView.getContext()).thenReturn(mock(FlutterActivity.class));
+
+ AccessibilityNodeInfo nodeInfo = mock(AccessibilityNodeInfo.class);
+ when(embeddedView.createAccessibilityNodeInfo()).thenReturn(nodeInfo);
+
+ AccessibilityNodeInfo result = accessibilityBridge.createAccessibilityNodeInfo(0);
+ assertNotNull(result);
+ assertEquals(result.getChildCount(), 1);
+ assertEquals(result.getClassName(), "android.view.View");
+ }
+
+ @Test
+ public void itProducesPlatformViewNodeForVirtualDisplay() {
+ PlatformViewsAccessibilityDelegate accessibilityDelegate =
+ mock(PlatformViewsAccessibilityDelegate.class);
+ AccessibilityViewEmbedder accessibilityViewEmbedder = mock(AccessibilityViewEmbedder.class);
+ AccessibilityBridge accessibilityBridge =
+ setUpBridge(
+ /*rootAccessibilityView=*/ null,
+ /*accessibilityChannel=*/ null,
+ /*accessibilityManager=*/ null,
+ /*contentResolver=*/ null,
+ accessibilityViewEmbedder,
+ accessibilityDelegate);
+
+ TestSemanticsNode platformView = new TestSemanticsNode();
+ platformView.platformViewId = 1;
+
+ TestSemanticsUpdate testSemanticsUpdate = platformView.toUpdate();
+ accessibilityBridge.updateSemantics(testSemanticsUpdate.buffer, testSemanticsUpdate.strings);
+
+ View embeddedView = mock(View.class);
+ when(accessibilityDelegate.getPlatformViewById(1)).thenReturn(embeddedView);
+ when(embeddedView.getContext()).thenReturn(mock(Activity.class));
+
+ accessibilityBridge.createAccessibilityNodeInfo(0);
+ verify(accessibilityViewEmbedder).getRootNode(eq(embeddedView), eq(0), any(Rect.class));
+ }
+
+ @Test
public void releaseDropsChannelMessageHandler() {
AccessibilityChannel mockChannel = mock(AccessibilityChannel.class);
AccessibilityManager mockManager = mock(AccessibilityManager.class);
@@ -317,6 +397,10 @@
float right = 0.0f;
float bottom = 0.0f;
final List<TestSemanticsNode> children = new ArrayList<TestSemanticsNode>();
+
+ public void addChild(TestSemanticsNode child) {
+ children.add(child);
+ }
// custom actions not supported.
TestSemanticsUpdate toUpdate() {
