Interrogation of the view hierarchy from an AccessibilityService.

1. Views are represented as AccessibilityNodeInfos to AccessibilityServices.

2. An accessibility service receives AccessibilityEvents and can ask
   for its source and gets an AccessibilityNodeInfo which can be used
   to get its parent and children infos and so on.

3. AccessibilityNodeInfo contains some attributes and actions that
   can be performed on the source.

4. AccessibilityService can request the system to preform an action
   on the source of an AccessibilityNodeInfo.

5. ViewAncestor provides an interaction connection to the
   AccessibiltyManagerService and an accessibility service uses
   its connection to the latter to interact with screen content.

6. AccessibilityService can interact ONLY with the focused window
   and all calls are routed through the AccessibilityManagerService
   which imposes security.

7. Hidden APIs on AccessibilityService can find AccessibilityNodeInfos
   based on some criteria. These API go through the AccessibilityManagerServcie
   for security check.

8. Some actions are hidden and are exposes only to eng builds for UI testing.

Change-Id: Ie34fa4219f350eb3f4f6f9f45b24f709bd98783c

2 files changed, 33 insertions, 1 deletions

diff --git a/core/java/android/widget/RelativeLayout.java b/core/java/android/widget/RelativeLayout.java
index 5562bf7..a4771d5 100644
--- a/core/java/android/widget/RelativeLayout.java
+++ b/core/java/android/widget/RelativeLayout.java
@@ -1441,6 +1441,7 @@ public class RelativeLayout extends ViewGroup {
             );
 
             private Node mNext;
+            private boolean mIsPooled;
 
             public void setNextPoolable(Node element) {
                 mNext = element;
@@ -1450,6 +1451,14 @@ public class RelativeLayout extends ViewGroup {
                 return mNext;
             }
 
+            public boolean isPooled() {
+                return mIsPooled;
+            }
+
+            public void setPooled(boolean isPooled) {
+                mIsPooled = isPooled;
+            }
+
             static Node acquire(View view) {
                 final Node node = sPool.acquire();
                 node.view = view;
diff --git a/core/java/android/widget/TextView.java b/core/java/android/widget/TextView.java
index 1d123f6..eba9d37 100644
--- a/core/java/android/widget/TextView.java
+++ b/core/java/android/widget/TextView.java
@@ -113,6 +113,7 @@ import android.view.ViewTreeObserver;
 import android.view.WindowManager;
 import android.view.accessibility.AccessibilityEvent;
 import android.view.accessibility.AccessibilityManager;
+import android.view.accessibility.AccessibilityNodeInfo;
 import android.view.animation.AnimationUtils;
 import android.view.inputmethod.BaseInputConnection;
 import android.view.inputmethod.CompletionInfo;
@@ -7647,7 +7648,18 @@ public class TextView extends View implements ViewTreeObserver.OnPreDrawListener
     protected int computeVerticalScrollExtent() {
         return getHeight() - getCompoundPaddingTop() - getCompoundPaddingBottom();
     }
-    
+
+    @Override
+    public void findViewsWithText(ArrayList<View> outViews, CharSequence text) {
+        CharSequence thisText = getText();
+        if (TextUtils.isEmpty(thisText)) {
+            return;
+        }
+        if (thisText.toString().toLowerCase().contains(text)) {
+            outViews.add(this);
+        }
+    }
+
     public enum BufferType {
         NORMAL, SPANNABLE, EDITABLE,
     }
@@ -7899,6 +7911,17 @@ public class TextView extends View implements ViewTreeObserver.OnPreDrawListener
         event.setPassword(isPassword);
     }
 
+    @Override
+    public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
+        super.onInitializeAccessibilityNodeInfo(info);
+
+        final boolean isPassword = hasPasswordTransformationMethod();
+        if (!isPassword) {
+            info.setText(getText());
+        }
+        info.setPassword(isPassword);
+    }
+
     void sendAccessibilityEventTypeViewTextChanged(CharSequence beforeText,
             int fromIndex, int removedCount, int addedCount) {
         AccessibilityEvent event =