Highlight the current talkback-focused element in the accessibility tree

Summary: Highlights the element corresponding to the view talkback is focused on in green in the ax tree (and updates live as talkback moves).

Reviewed By: blavalla

Differential Revision: D9021542

fbshipit-source-id: c3bf6f5625aacb0cd054032b33a50541b88b2eaf

android/src/main/java/com/facebook/sonar/plugins/inspector/InspectorSonarPlugin.java

@@ -10,6 +10,8 @@ package com.facebook.sonar.plugins.inspector;
 
 import android.app.Application;
 import android.content.Context;
+import android.support.v4.view.ViewCompat;
+import android.view.accessibility.AccessibilityEvent;
 import android.view.MotionEvent;
 import android.view.View;
 import android.view.ViewGroup;
@@ -170,20 +172,41 @@ public class InspectorSonarPlugin implements SonarPlugin {
         @Override
         public void onReceiveOnMainThread(SonarObject params, SonarResponder responder)
             throws Exception {
-          List<View> viewRoots = mApplication.getViewRoots();
-          // for now only works if one view root
-          if (viewRoots.size() != 1) {
-            responder.error(
-                new SonarObject.Builder().put("message", "Too many view roots.").build());
-            return;
+          final List<View> viewRoots = mApplication.getViewRoots();
+
+          ViewGroup root = null;
+          for (int i = viewRoots.size() - 1; i >= 0; i--) {
+            if (viewRoots.get(i) instanceof ViewGroup) {
+              root = (ViewGroup) viewRoots.get(i);
+              break;
+            }
           }
-          SonarObject response = getAXNode(trackObject(viewRoots.get(0)));
-          if (response == null) {
-            responder.error(
-                new SonarObject.Builder().put("message", "AX root node returned null.").build());
-            return;
+
+          if (root != null) {
+
+            // unlikely, but check to make sure accessibility functionality doesn't change
+            if (!ViewCompat.hasAccessibilityDelegate(root)) {
+              
+              // add delegate to root to catch accessibility events so we can update focus in sonar
+              root.setAccessibilityDelegate(new View.AccessibilityDelegate() {
+
+                @Override
+                public boolean onRequestSendAccessibilityEvent(ViewGroup host, View child, AccessibilityEvent event) {
+                  int eventType = event.getEventType();
+                  if (eventType == AccessibilityEvent.TYPE_VIEW_ACCESSIBILITY_FOCUSED || eventType == AccessibilityEvent.TYPE_VIEW_ACCESSIBILITY_FOCUS_CLEARED) {
+                    mConnection.send("axFocusEvent",
+                            new SonarObject.Builder()
+                                    .put("isFocus", eventType == AccessibilityEvent.TYPE_VIEW_ACCESSIBILITY_FOCUSED)
+                                    .build());
+                  }
+
+                  return super.onRequestSendAccessibilityEvent(host, child, event);
+                }
+              });
+            }
+
+            responder.success(getAXNode(trackObject(root)));
           }
-          responder.success(response);
         }
       };
 
@@ -550,6 +573,7 @@ public class InspectorSonarPlugin implements SonarPlugin {
         .put("data", data)
         .put("children", children)
         .put("attributes", attributes)
+        .put("extraInfo", descriptor.getExtraInfo(obj))
         .build();
   }
 

android/src/main/java/com/facebook/sonar/plugins/inspector/descriptors/TextViewDescriptor.java

@@ -131,6 +131,12 @@ public class TextViewDescriptor extends NodeDescriptor<TextView> {
     return descriptor.getAXAttributes(node);
   }
 
+  @Override
+  public SonarObject getExtraInfo(TextView node) {
+    final NodeDescriptor descriptor = descriptorForClass(View.class);
+    return descriptor.getExtraInfo(node);
+  }
+
   @Override
   public void setHighlighted(TextView node, boolean selected) throws Exception {
     final NodeDescriptor descriptor = descriptorForClass(View.class);

android/src/main/java/com/facebook/sonar/plugins/inspector/descriptors/ViewDescriptor.java

@@ -444,6 +444,7 @@ public class ViewDescriptor extends NodeDescriptor<View> {
     return attributes;
   }
 
+  @Override
   public List<Named<String>> getAXAttributes(View node) throws Exception {
     List<Named<String>> attributes = new ArrayList<>();
     String role = AccessibilityRoleUtil.getRole(node).toString();
@@ -453,6 +454,11 @@ public class ViewDescriptor extends NodeDescriptor<View> {
     return attributes;
   }
 
+  @Override
+  public SonarObject getExtraInfo(View node) {
+    return new SonarObject.Builder().put("focused", AccessibilityUtil.isAXFocused(node)).build();
+  }
+
   @Nullable
   private static String getResourceId(View node) {
     final int id = node.getId();

android/src/main/java/com/facebook/sonar/plugins/inspector/descriptors/ViewGroupDescriptor.java

@@ -235,6 +235,12 @@ public class ViewGroupDescriptor extends NodeDescriptor<ViewGroup> {
     return descriptor.getAXAttributes(node);
   }
 
+  @Override
+  public SonarObject getExtraInfo(ViewGroup node) {
+    final NodeDescriptor descriptor = descriptorForClass(View.class);
+    return descriptor.getExtraInfo(node);
+  }
+
   @Override
   public void setHighlighted(ViewGroup node, boolean selected) throws Exception {
     final NodeDescriptor descriptor = descriptorForClass(View.class);

android/src/main/java/com/facebook/sonar/plugins/inspector/descriptors/utils/AccessibilityUtil.java

@@ -420,6 +420,18 @@ public final class AccessibilityUtil {
     return nodeInfoProps.build();
   }
 
+  public static boolean isAXFocused(View view) {
+    final AccessibilityNodeInfoCompat nodeInfo =
+            ViewAccessibilityHelper.createNodeInfoFromView(view);
+    if (nodeInfo == null) {
+      return false;
+    } else {
+      boolean focused = nodeInfo.isAccessibilityFocused();
+      nodeInfo.recycle();
+      return focused;
+    }
+  }
+
   /**
    * Modifies a {@link SonarObject.Builder} to add Talkback-specific Accessibiltiy properties to be
    * shown in the Sonar Layout Inspector.

android/src/main/java/com/facebook/sonar/plugins/litho/LithoViewDescriptor.java

@@ -117,6 +117,12 @@ public class LithoViewDescriptor extends NodeDescriptor<LithoView> {
     return descriptor.getAXAttributes(node);
   }
 
+  @Override
+  public SonarObject getExtraInfo(LithoView node) {
+    final NodeDescriptor descriptor = descriptorForClass(ViewGroup.class);
+    return descriptor.getExtraInfo(node);
+  }
+
   @Override
   public void setHighlighted(LithoView node, boolean selected) throws Exception {
     final NodeDescriptor descriptor = descriptorForClass(ViewGroup.class);