Add live region politeness to View, AccessibilityNodeInfo

Alters the content change API to contain a bit mask of types of
changes represented by the event. Live regions send CONTENT_CHANGED
events immediately. Removes unused APIs for EXPANDABLE/EXPANDED.

BUG: 10527284
Change-Id: I21523e85e47df23706976dc0a8bf615f83072c04

3 files changed, 80 insertions, 109 deletions

diff --git a/core/java/android/view/accessibility/AccessibilityEvent.java b/core/java/android/view/accessibility/AccessibilityEvent.java
index 82c8163..7e2bffa 100644
--- a/core/java/android/view/accessibility/AccessibilityEvent.java
+++ b/core/java/android/view/accessibility/AccessibilityEvent.java
@@ -326,7 +326,7 @@ import java.util.List;
  * <em>Properties:</em></br>
  * <ul>
  *   <li>{@link #getEventType()} - The type of the event.</li>
- *   <li>{@link #getContentChangeType()} - The type of content change.</li>
+ *   <li>{@link #getContentChangeTypes()} - The type of content changes.</li>
  *   <li>{@link #getSource()} - The source info (for registered clients).</li>
  *   <li>{@link #getClassName()} - The class name of the source.</li>
  *   <li>{@link #getPackageName()} - The package name of the source.</li>
@@ -663,15 +663,27 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
 
     /**
      * Change type for {@link #TYPE_WINDOW_CONTENT_CHANGED} event:
-     * The subtree rooted at the source node changed.
+     * The type of change is not defined.
      */
-    public static final int CONTENT_CHANGE_TYPE_SUBTREE = 0;
+    public static final int CONTENT_CHANGE_TYPE_UNDEFINED = 0x00000000;
 
     /**
      * Change type for {@link #TYPE_WINDOW_CONTENT_CHANGED} event:
-     * Only the source node changed.
+     * A node in the subtree rooted at the source node was added or removed.
      */
-    public static final int CONTENT_CHANGE_TYPE_NODE = 1;
+    public static final int CONTENT_CHANGE_TYPE_SUBTREE = 0x00000001;
+
+    /**
+     * Change type for {@link #TYPE_WINDOW_CONTENT_CHANGED} event:
+     * The node's text changed.
+     */
+    public static final int CONTENT_CHANGE_TYPE_TEXT = 0x00000002;
+
+    /**
+     * Change type for {@link #TYPE_WINDOW_CONTENT_CHANGED} event:
+     * The node's content description changed.
+     */
+    public static final int CONTENT_CHANGE_TYPE_CONTENT_DESCRIPTION = 0x00000004;
 
     /**
      * Mask for {@link AccessibilityEvent} all types.
@@ -708,7 +720,7 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
     private long mEventTime;
     int mMovementGranularity;
     int mAction;
-    int mContentChangeType;
+    int mContentChangeTypes;
 
     private final ArrayList<AccessibilityRecord> mRecords = new ArrayList<AccessibilityRecord>();
 
@@ -728,7 +740,7 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
         mEventType = event.mEventType;
         mMovementGranularity = event.mMovementGranularity;
         mAction = event.mAction;
-        mContentChangeType = event.mContentChangeType;
+        mContentChangeTypes = event.mContentChangeTypes;
         mEventTime = event.mEventTime;
         mPackageName = event.mPackageName;
     }
@@ -792,30 +804,33 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
     }
 
     /**
-     * Gets the type of node tree change signaled by an
-     * {@link #TYPE_WINDOW_CONTENT_CHANGED} event.
+     * Gets the bit mask of change types signaled by an
+     * {@link #TYPE_WINDOW_CONTENT_CHANGED} event. A single event may represent
+     * multiple change types.
      *
-     * @see #CONTENT_CHANGE_TYPE_NODE
-     * @see #CONTENT_CHANGE_TYPE_SUBTREE
-     *
-     * @return The change type.
+     * @return The bit mask of change types. One or more of:
+     *         <ul>
+     *         <li>{@link AccessibilityEvent#CONTENT_CHANGE_TYPE_CONTENT_DESCRIPTION}
+     *         <li>{@link AccessibilityEvent#CONTENT_CHANGE_TYPE_SUBTREE}
+     *         <li>{@link AccessibilityEvent#CONTENT_CHANGE_TYPE_TEXT}
+     *         <li>{@link AccessibilityEvent#CONTENT_CHANGE_TYPE_UNDEFINED}
+     *         </ul>
      */
-    public int getContentChangeType() {
-        return mContentChangeType;
+    public int getContentChangeTypes() {
+        return mContentChangeTypes;
     }
 
     /**
-     * Sets the type of node tree change signaled by an
+     * Sets the bit mask of node tree changes signaled by an
      * {@link #TYPE_WINDOW_CONTENT_CHANGED} event.
      *
-     * @see #CONTENT_CHANGE_TYPE_NODE
-     * @see #CONTENT_CHANGE_TYPE_SUBTREE
-     *
-     * @param changeType The change type.
+     * @param changeTypes The bit mask of change types.
+     * @throws IllegalStateException If called from an AccessibilityService.
+     * @see #getContentChangeTypes()
      */
-    public void setContentChangeType(int changeType) {
+    public void setContentChangeTypes(int changeTypes) {
         enforceNotSealed();
-        mContentChangeType = changeType;
+        mContentChangeTypes = changeTypes;
     }
 
     /**
@@ -985,7 +1000,7 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
         mEventType = 0;
         mMovementGranularity = 0;
         mAction = 0;
-        mContentChangeType = 0;
+        mContentChangeTypes = 0;
         mPackageName = null;
         mEventTime = 0;
         while (!mRecords.isEmpty()) {
@@ -1004,7 +1019,7 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
         mEventType = parcel.readInt();
         mMovementGranularity = parcel.readInt();
         mAction = parcel.readInt();
-        mContentChangeType = parcel.readInt();
+        mContentChangeTypes = parcel.readInt();
         mPackageName = TextUtils.CHAR_SEQUENCE_CREATOR.createFromParcel(parcel);
         mEventTime = parcel.readLong();
         mConnectionId = parcel.readInt();
@@ -1057,7 +1072,7 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
         parcel.writeInt(mEventType);
         parcel.writeInt(mMovementGranularity);
         parcel.writeInt(mAction);
-        parcel.writeInt(mContentChangeType);
+        parcel.writeInt(mContentChangeTypes);
         TextUtils.writeToParcel(mPackageName, parcel, 0);
         parcel.writeLong(mEventTime);
         parcel.writeInt(mConnectionId);
@@ -1119,7 +1134,7 @@ public final class AccessibilityEvent extends AccessibilityRecord implements Par
         builder.append(super.toString());
         if (DEBUG) {
             builder.append("\n");
-            builder.append("; ContentChangeType: ").append(mContentChangeType);
+            builder.append("; ContentChangeTypes: ").append(mContentChangeTypes);
             builder.append("; sourceWindowId: ").append(mSourceWindowId);
             builder.append("; mSourceNodeId: ").append(mSourceNodeId);
             for (int i = 0; i < mRecords.size(); i++) {
diff --git a/core/java/android/view/accessibility/AccessibilityNodeInfo.java b/core/java/android/view/accessibility/AccessibilityNodeInfo.java
index c61516b..9fc37cf 100644
--- a/core/java/android/view/accessibility/AccessibilityNodeInfo.java
+++ b/core/java/android/view/accessibility/AccessibilityNodeInfo.java
@@ -418,19 +418,13 @@ public class AccessibilityNodeInfo implements Parcelable {
 
     private static final int BOOLEAN_PROPERTY_EDITABLE = 0x00001000;
 
-    private static final int BOOLEAN_PROPERTY_LIVE_REGION = 0x00002000;
+    private static final int BOOLEAN_PROPERTY_OPENS_POPUP = 0x00002000;
 
-    private static final int BOOLEAN_PROPERTY_OPENS_POPUP = 0x00004000;
+    private static final int BOOLEAN_PROPERTY_DISMISSABLE = 0x00004000;
 
-    private static final int BOOLEAN_PROPERTY_EXPANDABLE = 0x00008000;
+    private static final int BOOLEAN_PROPERTY_MULTI_LINE = 0x00008000;
 
-    private static final int BOOLEAN_PROPERTY_EXPANDED = 0x00010000;
-
-    private static final int BOOLEAN_PROPERTY_DISMISSABLE = 0x00020000;
-
-    private static final int BOOLEAN_PROPERTY_MULTI_LINE = 0x00040000;
-
-    private static final int BOOLEAN_PROPERTY_CONTENT_INVALID = 0x00080000;
+    private static final int BOOLEAN_PROPERTY_CONTENT_INVALID = 0x00010000;
 
     /**
      * Bits that provide the id of a virtual descendant of a view.
@@ -517,6 +511,7 @@ public class AccessibilityNodeInfo implements Parcelable {
     private int mTextSelectionStart = UNDEFINED;
     private int mTextSelectionEnd = UNDEFINED;
     private int mInputType = InputType.TYPE_NULL;
+    private int mLiveRegion = View.ACCESSIBILITY_LIVE_REGION_NONE;
 
     private Bundle mExtras;
 
@@ -1471,39 +1466,42 @@ public class AccessibilityNodeInfo implements Parcelable {
     }
 
     /**
-     * Gets if the node is a live region.
+     * Gets the node's live region mode.
      * <p>
-     * A live region is a node that contains information that is important
-     * for the user and when it changes the user has to be notified. For
-     * example, if the user plays a video and the application shows a
-     * progress indicator with the percentage of buffering, then the progress
-     * indicator should be marked as a live region.
-     * </p>
+     * A live region is a node that contains information that is important for
+     * the user and when it changes the user should be notified. For example,
+     * in a login screen with a TextView that displays an "incorrect password"
+     * notification, that view should be marked as a live region with mode
+     * {@link View#ACCESSIBILITY_LIVE_REGION_POLITE}.
      * <p>
-     * It is the responsibility of the accessibility
-     * service to monitor this region and notify the user if it changes.
-     * </p>
+     * It is the responsibility of the accessibility service to monitor
+     * {@link AccessibilityEvent#TYPE_WINDOW_CONTENT_CHANGED} events indicating
+     * changes to live region nodes and their children.
      *
-     * @return If the node is a live region.
+     * @return The live region mode, or
+     *         {@link View#ACCESSIBILITY_LIVE_REGION_NONE} if the view is not a
+     *         live region.
+     * @see android.view.View#getAccessibilityLiveRegion()
      */
-    public boolean isLiveRegion() {
-        return getBooleanProperty(BOOLEAN_PROPERTY_LIVE_REGION);
+    public int getLiveRegion() {
+        return mLiveRegion;
     }
 
     /**
-     * Sets if the node is a live region for whose changes the user
-     * should be notified. It is the responsibility of the accessibility
-     * service to monitor this region and notify the user if it changes.
+     * Sets the node's live region mode.
      * <p>
-     *   <strong>Note:</strong> Cannot be called from an
-     *   {@link android.accessibilityservice.AccessibilityService}.
-     *   This class is made immutable before being delivered to an AccessibilityService.
-     * </p>
+     * <strong>Note:</strong> Cannot be called from an
+     * {@link android.accessibilityservice.AccessibilityService}. This class is
+     * made immutable before being delivered to an AccessibilityService.
      *
-     * @param liveRegion If the node is a live region.
+     * @param mode The live region mode, or
+     *        {@link View#ACCESSIBILITY_LIVE_REGION_NONE} if the view is not a
+     *        live region.
+     * @see android.view.View#setAccessibilityLiveRegion(int)
      */
-    public void setLiveRegion(boolean liveRegion) {
-        setBooleanProperty(BOOLEAN_PROPERTY_LIVE_REGION, liveRegion);
+    public void setLiveRegion(int mode) {
+        enforceNotSealed();
+        mLiveRegion = mode;
     }
 
     /**
@@ -1554,52 +1552,6 @@ public class AccessibilityNodeInfo implements Parcelable {
     }
 
     /**
-     * Gets if the node can be expanded.
-     *
-     * @return If the node can be expanded.
-     */
-    public boolean isExpandable() {
-        return getBooleanProperty(BOOLEAN_PROPERTY_EXPANDABLE);
-    }
-
-    /**
-     * Sets if the node can be expanded.
-     * <p>
-     *   <strong>Note:</strong> Cannot be called from an
-     *   {@link android.accessibilityservice.AccessibilityService}.
-     *   This class is made immutable before being delivered to an AccessibilityService.
-     * </p>
-     *
-     * @param expandable If the node can be expanded.
-     */
-    public void setExpandable(boolean expandable) {
-        setBooleanProperty(BOOLEAN_PROPERTY_EXPANDABLE, expandable);
-    }
-
-    /**
-     * Gets if the node is expanded.
-     *
-     * @return If the node is expanded.
-     */
-    public boolean isExpanded() {
-        return getBooleanProperty(BOOLEAN_PROPERTY_EXPANDED);
-    }
-
-    /**
-     * Sets if the node is expanded.
-     * <p>
-     *   <strong>Note:</strong> Cannot be called from an
-     *   {@link android.accessibilityservice.AccessibilityService}.
-     *   This class is made immutable before being delivered to an AccessibilityService.
-     * </p>
-     *
-     * @param expanded If the node is expanded.
-     */
-    public void setExpanded(boolean expanded) {
-        setBooleanProperty(BOOLEAN_PROPERTY_EXPANDED, expanded);
-    }
-
-    /**
      * Gets if the node can be dismissed.
      *
      * @return If the node can be dismissed.
@@ -2203,6 +2155,7 @@ public class AccessibilityNodeInfo implements Parcelable {
         parcel.writeInt(mTextSelectionStart);
         parcel.writeInt(mTextSelectionEnd);
         parcel.writeInt(mInputType);
+        parcel.writeInt(mLiveRegion);
 
         if (mExtras != null) {
             parcel.writeInt(1);
@@ -2276,6 +2229,7 @@ public class AccessibilityNodeInfo implements Parcelable {
         mTextSelectionStart = other.mTextSelectionStart;
         mTextSelectionEnd = other.mTextSelectionEnd;
         mInputType = other.mInputType;
+        mLiveRegion = other.mLiveRegion;
         if (other.mExtras != null && !other.mExtras.isEmpty()) {
             getExtras().putAll(other.mExtras);
         }
@@ -2334,6 +2288,7 @@ public class AccessibilityNodeInfo implements Parcelable {
         mTextSelectionEnd = parcel.readInt();
 
         mInputType = parcel.readInt();
+        mLiveRegion = parcel.readInt();
 
         if (parcel.readInt() == 1) {
             getExtras().putAll(parcel.readBundle());
@@ -2389,6 +2344,7 @@ public class AccessibilityNodeInfo implements Parcelable {
         mTextSelectionStart = UNDEFINED;
         mTextSelectionEnd = UNDEFINED;
         mInputType = InputType.TYPE_NULL;
+        mLiveRegion = View.ACCESSIBILITY_LIVE_REGION_NONE;
         if (mExtras != null) {
             mExtras.clear();
         }
diff --git a/core/java/android/view/accessibility/AccessibilityNodeInfoCache.java b/core/java/android/view/accessibility/AccessibilityNodeInfoCache.java
index 1fde2fa..3596daa 100644
--- a/core/java/android/view/accessibility/AccessibilityNodeInfoCache.java
+++ b/core/java/android/view/accessibility/AccessibilityNodeInfoCache.java
@@ -91,11 +91,11 @@ public class AccessibilityNodeInfoCache {
                 case AccessibilityEvent.TYPE_WINDOW_CONTENT_CHANGED: {
                     synchronized (mLock) {
                         final long sourceId = event.getSourceNodeId();
-                        if (event.getContentChangeType()
-                                == AccessibilityEvent.CONTENT_CHANGE_TYPE_NODE) {
-                            refreshCachedNode(sourceId);
-                        } else {
+                        if ((event.getContentChangeTypes()
+                                & AccessibilityEvent.CONTENT_CHANGE_TYPE_SUBTREE) != 0) {
                             clearSubTreeLocked(sourceId);
+                        } else {
+                            refreshCachedNode(sourceId);
                         }
                     }
                 } break;