Added a callback for AutoFillService.

So far AutoFillService only received the assist data from framework; in
this CL, it also offers a method where the auto-fill provider can send
the auto-fill data back to framework.

The workflow is:

- AFMSI calls a new AM method (requestAutoFillData(), instead
  of requestAssistContextExtras()).
- The assist receiver is located in the app, not on system service.
- AM uses a new request type (ASSIST_CONTEXT_AUTOFILL) to request the
  assist data to the activity.
- ViewStructure has a new setAutoFillId() method which is used to set an
  unique id for the view.
- View uses the accessibility id to implement the auto-fill id.
- When the activity fullfills the request, it creates an IAutoFillCallback
  remote object - that will be used to set the auto-fill fields - and
  returns it in the assist bundle (using the
  VoiceInteractionSession.KEY_AUTO_FILL_CALLBACK key).
- The app-visible AutoFillService class offers an onFillRequest() method,
  which contains the assist data and a FillCallback used to handle it.

BUG: 31001899
Test: manually built and ran it

Change-Id: I3d208c14e81022dc96dd03f38bbe25a778b24a67

15 files changed, 465 insertions, 90 deletions

diff --git a/core/java/android/app/Activity.java b/core/java/android/app/Activity.java
index b38133901b30..6f53f13662be 100644
--- a/core/java/android/app/Activity.java
+++ b/core/java/android/app/Activity.java
@@ -53,7 +53,6 @@ import android.graphics.Bitmap;
 import android.graphics.Canvas;
 import android.graphics.Color;
 import android.graphics.drawable.Drawable;
-import android.hardware.input.InputManager;
 import android.media.AudioManager;
 import android.media.session.MediaController;
 import android.net.Uri;
@@ -70,6 +69,9 @@ import android.os.ServiceManager.ServiceNotFoundException;
 import android.os.StrictMode;
 import android.os.SystemProperties;
 import android.os.UserHandle;
+import android.service.autofill.FillableInputField;
+import android.service.autofill.AutoFillService;
+import android.service.autofill.IAutoFillCallback;
 import android.text.Selection;
 import android.text.SpannableStringBuilder;
 import android.text.TextUtils;
@@ -90,8 +92,6 @@ import android.view.ContextMenu.ContextMenuInfo;
 import android.view.ContextThemeWrapper;
 import android.view.DragAndDropPermissions;
 import android.view.DragEvent;
-import android.view.InputDevice;
-import android.view.KeyCharacterMap;
 import android.view.KeyEvent;
 import android.view.KeyboardShortcutGroup;
 import android.view.KeyboardShortcutInfo;
@@ -113,9 +113,11 @@ import android.view.WindowManager;
 import android.view.WindowManagerGlobal;
 import android.view.accessibility.AccessibilityEvent;
 import android.widget.AdapterView;
+import android.widget.EditText;
 import android.widget.Toast;
 import android.widget.Toolbar;
 
+import com.android.internal.annotations.GuardedBy;
 import com.android.internal.app.IVoiceInteractor;
 import com.android.internal.app.ToolbarActionBar;
 import com.android.internal.app.WindowDecorActionBar;
@@ -802,11 +804,13 @@ public class Activity extends ContextThemeWrapper
         private boolean mReleased;
         private boolean mUpdated;
     }
-    private final ArrayList<ManagedCursor> mManagedCursors =
-        new ArrayList<ManagedCursor>();
 
-    // protected by synchronized (this)
+    @GuardedBy("mManagedCursors")
+    private final ArrayList<ManagedCursor> mManagedCursors = new ArrayList<>();
+
+    @GuardedBy("this")
     int mResultCode = RESULT_CANCELED;
+    @GuardedBy("this")
     Intent mResultData = null;
 
     private TranslucentConversionListener mTranslucentCallback;
@@ -837,6 +841,9 @@ public class Activity extends ContextThemeWrapper
     private boolean mHasCurrentPermissionsRequest;
     private boolean mEatKeyUpEvent;
 
+    @GuardedBy("this")
+    private IAutoFillCallback mAutoFillCallback;
+
     private static native String getDlWarning();
 
     /** Return the intent that started this activity. */
@@ -1688,6 +1695,53 @@ public class Activity extends ContextThemeWrapper
     }
 
     /**
+     * Lazily gets the {@code IAutoFillCallback} for this activitity.
+     *
+     * <p>This callback is used by the {@link AutoFillService} app to auto-fill the activity fields.
+     */
+    IAutoFillCallback getAutoFillCallback() {
+        synchronized (this) {
+            if (mAutoFillCallback == null) {
+                mAutoFillCallback = new IAutoFillCallback.Stub() {
+                    @Override
+                    public void autofill(@SuppressWarnings("rawtypes") List fields)
+                            throws RemoteException {
+                        runOnUiThread(() -> {
+                            final View root = getWindow().getDecorView().getRootView();
+                            for (Object field : fields) {
+                                if (!(field instanceof FillableInputField)) {
+                                    Slog.w(TAG,  "autofill(): invalid type " + field.getClass());
+                                    continue;
+                                }
+                                FillableInputField autoFillField = (FillableInputField) field;
+                                final int viewId = autoFillField.getId();
+                                final View view = root.findViewByAccessibilityIdTraversal(viewId);
+                                // TODO: should handle other types of view as well, but that will
+                                // require:
+                                // - a new interface like AutoFillable
+                                // - a way for the views to define the type of the autofield value
+                                if ((view instanceof EditText)) {
+                                    ((EditText) view).setText(autoFillField.getValue());
+                                }
+                            }
+                        });
+                    }
+
+                    @Override
+                    public void showError(String message) {
+                        runOnUiThread(() -> {
+                            // TODO: temporary show a toast until it uses the Snack bar.
+                            Toast.makeText(Activity.this, "Auto-fill request failed: " + message,
+                                    Toast.LENGTH_LONG).show();
+                        });
+                    }
+                };
+            }
+        }
+        return mAutoFillCallback;
+    }
+
+    /**
      * Request the Keyboard Shortcuts screen to show up. This will trigger
      * {@link #onProvideKeyboardShortcuts} to retrieve the shortcuts for the foreground activity.
      */
@@ -5974,6 +6028,11 @@ public class Activity extends ContextThemeWrapper
             getWindow().peekDecorView().getViewRootImpl().dump(prefix, fd, writer, args);
         }
 
+        if (mAutoFillCallback != null) {
+            writer.print(prefix); writer.print("mAutoFillCallback: " );
+                    writer.println(mAutoFillCallback);
+        }
+
         mHandler.getLooper().dump(new PrintWriterPrinter(writer), prefix);
     }
 
diff --git a/core/java/android/app/ActivityManager.java b/core/java/android/app/ActivityManager.java
index 4a39e4a4cb50..c55d3b8208d7 100644
--- a/core/java/android/app/ActivityManager.java
+++ b/core/java/android/app/ActivityManager.java
@@ -447,6 +447,9 @@ public class ActivityManager {
     /** @hide requestType for assist context: generate full AssistStructure. */
     public static final int ASSIST_CONTEXT_FULL = 1;
 
+    /** @hide requestType for assist context: generate full AssistStructure for auto-fill. */
+    public static final int ASSIST_CONTEXT_AUTOFILL = 2;
+
     /** @hide Flag for registerUidObserver: report changes in process state. */
     public static final int UID_OBSERVER_PROCSTATE = 1<<0;
 
diff --git a/core/java/android/app/ActivityManagerNative.java b/core/java/android/app/ActivityManagerNative.java
index 199fda4cd09c..cabdd4b6ac00 100644
--- a/core/java/android/app/ActivityManagerNative.java
+++ b/core/java/android/app/ActivityManagerNative.java
@@ -109,4 +109,4 @@ public abstract class ActivityManagerNative {
     static public void noteAlarmFinish(PendingIntent ps, int sourceUid, String tag) {
         ActivityManager.noteAlarmFinish(ps, sourceUid, tag);
     }
-}
\ No newline at end of file
+}
diff --git a/core/java/android/app/ActivityThread.java b/core/java/android/app/ActivityThread.java
index a3414f458ef3..d41a7e8102de 100644
--- a/core/java/android/app/ActivityThread.java
+++ b/core/java/android/app/ActivityThread.java
@@ -88,6 +88,8 @@ import android.provider.Downloads;
 import android.provider.Settings;
 import android.security.NetworkSecurityPolicy;
 import android.security.net.config.NetworkSecurityConfigProvider;
+import android.service.autofill.IAutoFillCallback;
+import android.service.voice.VoiceInteractionSession;
 import android.util.AndroidRuntimeException;
 import android.util.ArrayMap;
 import android.util.DisplayMetrics;
@@ -2881,16 +2883,24 @@ public final class ActivityThread {
                 mLastAssistStructures.remove(i);
             }
         }
+        // Filling for auto-fill has a few differences:
+        // - it does not need an AssistContent
+        // - it does not call onProvideAssistData()
+        // - it needs an IAutoFillCallback
+        boolean forAutofill = cmd.requestType == ActivityManager.ASSIST_CONTEXT_AUTOFILL;
+
         Bundle data = new Bundle();
         AssistStructure structure = null;
-        AssistContent content = new AssistContent();
+        AssistContent content = forAutofill ? null : new AssistContent();
         ActivityClientRecord r = mActivities.get(cmd.activityToken);
         Uri referrer = null;
         if (r != null) {
             r.activity.getApplication().dispatchOnProvideAssistData(r.activity, data);
-            r.activity.onProvideAssistData(data);
+            if (!forAutofill) {
+                r.activity.onProvideAssistData(data);
+            }
             referrer = r.activity.onProvideReferrer();
-            if (cmd.requestType == ActivityManager.ASSIST_CONTEXT_FULL) {
+            if (cmd.requestType == ActivityManager.ASSIST_CONTEXT_FULL || forAutofill) {
                 structure = new AssistStructure(r.activity);
                 Intent activityIntent = r.activity.getIntent();
                 if (activityIntent != null && (r.window == null ||
@@ -2900,11 +2910,21 @@ public final class ActivityThread {
                     intent.setFlags(intent.getFlags() & ~(Intent.FLAG_GRANT_WRITE_URI_PERMISSION
                             | Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION));
                     intent.removeUnsafeExtras();
-                    content.setDefaultIntent(intent);
+                    if (forAutofill) {
+                        IAutoFillCallback autoFillCallback = r.activity.getAutoFillCallback();
+                        data.putBinder(VoiceInteractionSession.KEY_AUTO_FILL_CALLBACK,
+                                autoFillCallback.asBinder());
+                    } else {
+                        content.setDefaultIntent(intent);
+                    }
                 } else {
-                    content.setDefaultIntent(new Intent());
+                    if (!forAutofill) {
+                        content.setDefaultIntent(new Intent());
+                    }
+                }
+                if (!forAutofill) {
+                    r.activity.onProvideAssistContent(content);
                 }
-                r.activity.onProvideAssistContent(content);
             }
         }
         if (structure == null) {
diff --git a/core/java/android/app/IActivityManager.aidl b/core/java/android/app/IActivityManager.aidl
index 9fe34c0e39bc..d63d37be9f2d 100644
--- a/core/java/android/app/IActivityManager.aidl
+++ b/core/java/android/app/IActivityManager.aidl
@@ -564,6 +564,8 @@ interface IActivityManager {
     void moveStackToDisplay(int stackId, int displayId) = 403;
     void enterPictureInPictureModeWithAspectRatio(in IBinder token, float aspectRatio) = 404;
     void setPictureInPictureAspectRatio(in IBinder token, float aspectRatio) = 405;
+    boolean requestAutoFillData(in IResultReceiver receiver, in Bundle receiverExtras,
+            in IBinder activityToken) = 406;
 
     // Please keep these transaction codes the same -- they are also
     // sent by C++ code. when a new method is added, use the next available transaction id.
diff --git a/core/java/android/app/assist/AssistStructure.java b/core/java/android/app/assist/AssistStructure.java
index 6b720c0a22f6..a6f23666cc6d 100644
--- a/core/java/android/app/assist/AssistStructure.java
+++ b/core/java/android/app/assist/AssistStructure.java
@@ -515,6 +515,7 @@ public class AssistStructure implements Parcelable {
         String mIdPackage;
         String mIdType;
         String mIdEntry;
+        int mAutoFillId = View.NO_ID;
         int mX;
         int mY;
         int mScrollX;
@@ -539,6 +540,7 @@ public class AssistStructure implements Parcelable {
         static final int FLAGS_ACTIVATED = 0x00002000;
         static final int FLAGS_CONTEXT_CLICKABLE = 0x00004000;
 
+        static final int FLAGS_HAS_AUTO_FILL_ID = 0x80000000;
         static final int FLAGS_HAS_MATRIX = 0x40000000;
         static final int FLAGS_HAS_ALPHA = 0x20000000;
         static final int FLAGS_HAS_ELEVATION = 0x10000000;
@@ -582,6 +584,9 @@ public class AssistStructure implements Parcelable {
                     }
                 }
             }
+            if ((flags&FLAGS_HAS_AUTO_FILL_ID) != 0) {
+                mAutoFillId = in.readInt();
+            }
             if ((flags&FLAGS_HAS_LARGE_COORDS) != 0) {
                 mX = in.readInt();
                 mY = in.readInt();
@@ -637,6 +642,9 @@ public class AssistStructure implements Parcelable {
             if (mId != View.NO_ID) {
                 flags |= FLAGS_HAS_ID;
             }
+            if (mAutoFillId != View.NO_ID) {
+                flags |= FLAGS_HAS_AUTO_FILL_ID;
+            }
             if ((mX&~0x7fff) != 0 || (mY&~0x7fff) != 0
                     || (mWidth&~0x7fff) != 0 | (mHeight&~0x7fff) != 0) {
                 flags |= FLAGS_HAS_LARGE_COORDS;
@@ -681,6 +689,9 @@ public class AssistStructure implements Parcelable {
                     }
                 }
             }
+            if ((flags&FLAGS_HAS_AUTO_FILL_ID) != 0) {
+                out.writeInt(mAutoFillId);
+            }
             if ((flags&FLAGS_HAS_LARGE_COORDS) != 0) {
                 out.writeInt(mX);
                 out.writeInt(mY);
@@ -751,6 +762,16 @@ public class AssistStructure implements Parcelable {
         }
 
         /**
+         * Returns the id that can be used to auto-fill the view.
+         *
+         * <p>It's only set when the {@link AssistStructure} is used for auto-filling purposes, not
+         * for assist.
+         */
+        public int getAutoFillId() {
+            return mAutoFillId;
+        }
+
+        /**
          * Returns the left edge of this view, in pixels, relative to the left edge of its parent.
          */
         public int getLeft() {
@@ -1322,6 +1343,11 @@ public class AssistStructure implements Parcelable {
         public Rect getTempRect() {
             return mAssist.mTmpRect;
         }
+
+        @Override
+        public void setAutoFillId(int autoFillId) {
+            mNode.mAutoFillId = autoFillId;
+        }
     }
 
     /** @hide */
diff --git a/core/java/android/service/autofill/AutoFillService.java b/core/java/android/service/autofill/AutoFillService.java
index 14ce009bedc6..83b2065f44fe 100644
--- a/core/java/android/service/autofill/AutoFillService.java
+++ b/core/java/android/service/autofill/AutoFillService.java
@@ -15,27 +15,37 @@
  */
 package android.service.autofill;
 
+import android.annotation.IntDef;
 import android.annotation.SdkConstant;
+import android.app.Activity;
 import android.app.Service;
 import android.app.assist.AssistStructure;
 import android.content.Intent;
 import android.os.Bundle;
+import android.os.CancellationSignal;
 import android.os.IBinder;
 import android.os.Looper;
 import android.os.Message;
+import android.os.RemoteException;
+import android.service.voice.VoiceInteractionSession;
 import android.util.Log;
 
 import com.android.internal.os.HandlerCaller;
+import com.android.internal.os.IResultReceiver;
 import com.android.internal.os.SomeArgs;
 
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
 /**
  * Top-level service of the current auto-fill service for a given user.
+ *
+ * <p>Apps providing auto-fill capabilities must extend this service.
  */
-// TODO: expand documentation
 public abstract class AutoFillService extends Service {
 
-    private static final String TAG = "AutoFillService";
-    private static final boolean DEBUG = true; // TODO: set to false once stable
+    static final String TAG = "AutoFillService";
+    static final boolean DEBUG = true; // TODO: set to false once stable
 
     /**
      * The {@link Intent} that must be declared as handled by the service.
@@ -47,11 +57,23 @@ public abstract class AutoFillService extends Service {
     public static final String SERVICE_INTERFACE = "android.service.autofill.AutoFillService";
 
     private static final int MSG_READY = 1;
-    private static final int MSG_NEW_SESSION = 2;
-    private static final int MSG_SESSION_FINISHED = 3;
-    private static final int MSG_SHUTDOWN = 4;
+    private static final int MSG_AUTO_FILL = 2;
+    private static final int MSG_SHUTDOWN = 3;
 
-    // TODO: add metadata?
+    private final IResultReceiver mAssistReceiver = new IResultReceiver.Stub() {
+        @Override
+        public void send(int resultCode, Bundle resultData) throws RemoteException {
+            final AssistStructure structure = resultData
+                    .getParcelable(VoiceInteractionSession.KEY_STRUCTURE);
+
+            final IBinder binder = resultData
+                    .getBinder(VoiceInteractionSession.KEY_AUTO_FILL_CALLBACK);
+
+            mHandlerCaller
+                .obtainMessageOO(MSG_AUTO_FILL, structure, binder).sendToTarget();
+        }
+
+    };
 
     private final IAutoFillService mInterface = new IAutoFillService.Stub() {
         @Override
@@ -60,15 +82,8 @@ public abstract class AutoFillService extends Service {
         }
 
         @Override
-        public void newSession(String token, Bundle data, int flags,
-                AssistStructure structure) {
-            mHandlerCaller.sendMessage(mHandlerCaller.obtainMessageIOOO(MSG_NEW_SESSION,
-                    flags, token, data, structure));
-        }
-
-        @Override
-        public void finishSession(String token) {
-            mHandlerCaller.sendMessage(mHandlerCaller.obtainMessageO(MSG_SESSION_FINISHED, token));
+        public IResultReceiver getAssistReceiver() {
+            return mAssistReceiver;
         }
 
         @Override
@@ -85,17 +100,11 @@ public abstract class AutoFillService extends Service {
                 case MSG_READY: {
                     onReady();
                     break;
-                } case MSG_NEW_SESSION: {
+                } case MSG_AUTO_FILL: {
                     final SomeArgs args = (SomeArgs) msg.obj;
-                    final int flags = args.argi1;
-                    final String token = (String) args.arg1;
-                    final Bundle data = (Bundle) args.arg2;
-                    final AssistStructure assistStructure = (AssistStructure) args.arg3;
-                    onNewSession(token, data, flags, assistStructure);
-                    break;
-                } case MSG_SESSION_FINISHED: {
-                    final String token = (String) msg.obj;
-                    onSessionFinished(token);
+                    final AssistStructure structure = (AssistStructure) args.arg1;
+                    final IBinder binder = (IBinder) args.arg2;
+                    autoFillActivity(structure, binder);
                     break;
                 } case MSG_SHUTDOWN: {
                     onShutdown();
@@ -121,6 +130,7 @@ public abstract class AutoFillService extends Service {
         if (SERVICE_INTERFACE.equals(intent.getAction())) {
             return mInterface.asBinder();
         }
+        Log.w(TAG, "Tried to bind to wrong intent: " + intent);
         return null;
     }
 
@@ -129,41 +139,26 @@ public abstract class AutoFillService extends Service {
      * to receive interaction from it.
      *
      * <p>You should generally do initialization here rather than in {@link #onCreate}.
-     *
-     * <p>Sub-classes should call it first, since it sets the reference to the sytem-server service.
      */
-    // TODO: rename to onConnected() / add onDisconnected()?
+    // TODO: rename to onConnect() / update javadoc
     public void onReady() {
         if (DEBUG) Log.d(TAG, "onReady()");
     }
 
     /**
-     * Called to receive data from the application that the user was requested auto-fill for.
+     * Handles an auto-fill request.
      *
-     * @param token unique token identifying the auto-fill session, it should be used when providing
-     * the auto-filled fields.
-     * @param data Arbitrary data supplied by the app through
-     * {@link android.app.Activity#onProvideAssistData Activity.onProvideAssistData}.
-     * May be {@code null} if data has been disabled by the user or device policy.
-     * @param startFlags currently always 0.
-     * @param structure If available, the structure definition of all windows currently
-     * displayed by the app.  May be {@code null} if auto-fill data has been disabled by the user
-     * or device policy; will be an empty stub if the application has disabled auto-fill
-     * by marking its window as secure.
+     * @param structure {@link Activity}'s view structure .
+     * @param cancellationSignal signal for observing cancel requests.
+     * @param callback object used to fulllfill the request.
      */
-    @SuppressWarnings("unused")
-    // TODO: take the factory approach where this method return a session, and move the callback
-    // methods (like autofill()) to the session.
-    public void onNewSession(String token, Bundle data, int startFlags, AssistStructure structure) {
-        if (DEBUG) Log.d(TAG, "onNewSession(): token=" + token);
-    }
+    public abstract void onFillRequest(AssistStructure structure,
+            CancellationSignal cancellationSignal, FillCallback callback);
 
-    /**
-     * Called when an auto-fill session is finished.
-     */
-    @SuppressWarnings("unused")
-    public void onSessionFinished(String token) {
-        if (DEBUG) Log.d(TAG, "onSessionFinished(): token=" + token);
+    private void autoFillActivity(AssistStructure structure, IBinder binder) {
+        final FillCallback callback = new FillCallback(binder);
+        // TODO: hook up the cancelationSignal
+        onFillRequest(structure, new CancellationSignal(), callback);
     }
 
     /**
@@ -172,7 +167,9 @@ public abstract class AutoFillService extends Service {
      *
      * <p> At this point this service may no longer be an active {@link AutoFillService}.
      */
+    // TODO: rename to onDisconnected() / update javadoc
     public void onShutdown() {
         if (DEBUG) Log.d(TAG, "onShutdown()");
     }
+
 }
diff --git a/core/java/android/service/autofill/FillCallback.java b/core/java/android/service/autofill/FillCallback.java
new file mode 100644
index 000000000000..bdcc93b0397c
--- /dev/null
+++ b/core/java/android/service/autofill/FillCallback.java
@@ -0,0 +1,146 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.service.autofill;
+
+import static android.service.autofill.AutoFillService.DEBUG;
+import static android.service.autofill.AutoFillService.TAG;
+
+import android.app.Activity;
+import android.app.assist.AssistStructure.ViewNode;
+import android.os.IBinder;
+import android.os.RemoteException;
+import android.util.Log;
+import android.util.SparseArray;
+
+import com.android.internal.util.Preconditions;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+/**
+ * Handles auto-fill requests from the {@link AutoFillService} into the {@link Activity} being
+ * auto-filled.
+ */
+public final class FillCallback {
+
+    private final IAutoFillCallback mCallback;
+
+    /** @hide */
+    FillCallback(IBinder binder) {
+        mCallback = IAutoFillCallback.Stub.asInterface(binder);
+    }
+
+    /**
+     * Auto-fills the {@link Activity}.
+     *
+     * @throws RuntimeException if an error occurred while auto-filling it.
+     */
+    public void onSuccess(FillData data) {
+        if (DEBUG) Log.d(TAG, "onSuccess(): data=" + data);
+
+        Preconditions.checkArgument(data != null, "data cannot be null");
+
+        try {
+            mCallback.autofill(data.asList());
+        } catch (RemoteException e) {
+            e.rethrowAsRuntimeException();
+        }
+    }
+
+    /**
+     * Notifies the activity that the auto-fill request failed.
+     */
+    public void onFailure(CharSequence message) {
+        if (DEBUG) Log.d(TAG, "onFailure(): message=" + message);
+
+        Preconditions.checkArgument(message != null, "message cannot be null");
+
+        try {
+            mCallback.showError(message.toString());
+        } catch (RemoteException e) {
+            e.rethrowAsRuntimeException();
+        }
+    }
+
+    /**
+     * Data used to fill the fields of an {@link Activity}.
+     *
+     * <p>This class is immutable.
+     */
+    public static final class FillData {
+
+        private final List<FillableInputField> mList;
+
+        private FillData(Builder builder) {
+            final int size = builder.mFields.size();
+            final List<FillableInputField> list = new ArrayList<>(size);
+            for (int i = 0; i < size; i++) {
+                list.add(builder.mFields.valueAt(i));
+            }
+            mList = Collections.unmodifiableList(list);
+            // TODO: use FastImmutableArraySet or a similar structure instead?
+        }
+
+        /**
+         * Gets the response as a {@code List} so it can be used in a binder call.
+         */
+        List<FillableInputField> asList() {
+            return mList;
+        }
+
+        @Override
+        public String toString() {
+            return "[AutoFillResponse: " + mList + "]";
+        }
+
+        /**
+         * Builder for {@link FillData} objects.
+         *
+         * <p>Typical usage:
+         *
+         * <pre class="prettyprint">
+         * FillCallback.FillData data = new FillCallback.FillData.Builder()
+         *     .setTextField(id1, "value 1")
+         *     .setTextField(id2, "value 2")
+         *     .build()
+         * </pre>
+         */
+        public static class Builder {
+            private final SparseArray<FillableInputField> mFields = new SparseArray<>();
+
+            /**
+             * Auto-fills a text field.
+             *
+             * @param id view id as returned by {@link ViewNode#getAutoFillId()}.
+             * @param text text to be auto-filled.
+             * @return same builder so it can be chained.
+             */
+            public Builder setTextField(int id, String text) {
+                mFields.put(id, FillableInputField.forText(id, text));
+                return this;
+            }
+
+            /**
+             * Builds a new {@link FillData} instance.
+             */
+            public FillData build() {
+                return new FillData(this);
+            }
+        }
+    }
+}
diff --git a/core/java/android/service/autofill/FillableInputField.java b/core/java/android/service/autofill/FillableInputField.java
new file mode 100644
index 000000000000..62950b40e5e1
--- /dev/null
+++ b/core/java/android/service/autofill/FillableInputField.java
@@ -0,0 +1,99 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.service.autofill;
+
+import android.app.assist.AssistStructure.ViewNode;
+import android.os.Parcel;
+import android.os.Parcelable;
+
+/**
+ * Represents a view field that can be auto-filled.
+ *
+ * <p>Currently only text-fields are supported, so the value of the field can be obtained through
+ * {@link #getValue()}.
+ *
+ * @hide
+ */
+public final class FillableInputField implements Parcelable {
+
+    private final int mId;
+    private final String mValue;
+
+    private FillableInputField(int id, String value) {
+        mId = id;
+        mValue = value;
+    }
+
+    private FillableInputField(Parcel parcel) {
+        mId = parcel.readInt();
+        mValue = parcel.readString();
+    }
+
+    /**
+     * Gets the view id as returned by {@link ViewNode#getAutoFillId()}.
+     */
+    public int getId() {
+        return mId;
+    }
+
+    /**
+     * Gets the value of this field.
+     */
+    public String getValue() {
+        return mValue;
+
+    }
+
+    @Override
+    public String toString() {
+        return "[AutoFillField: " + mId + "=" + mValue + "]";
+    }
+
+    /**
+     * Creates an {@code AutoFillField} for a text field.
+     *
+     * @param id view id as returned by {@link ViewNode#getAutoFillId()}.
+     * @param text value to be auto-filled.
+     */
+    public static FillableInputField forText(int id, String text) {
+        return new FillableInputField(id, text);
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(Parcel parcel, int flags) {
+        parcel.writeInt(mId);
+        parcel.writeString(mValue);
+    }
+
+    public static final Parcelable.Creator<FillableInputField> CREATOR =
+            new Parcelable.Creator<FillableInputField>() {
+        @Override
+        public FillableInputField createFromParcel(Parcel source) {
+            return new FillableInputField(source);
+        }
+
+        @Override
+        public FillableInputField[] newArray(int size) {
+            return new FillableInputField[size];
+        }
+    };
+}
diff --git a/core/java/android/service/autofill/IAutoFillCallback.aidl b/core/java/android/service/autofill/IAutoFillCallback.aidl
new file mode 100644
index 000000000000..db8ef96976a2
--- /dev/null
+++ b/core/java/android/service/autofill/IAutoFillCallback.aidl
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.service.autofill;
+
+import java.util.List;
+
+/**
+ * @hide
+ */
+interface IAutoFillCallback {
+    void autofill(in List values);
+    void showError(String message);
+}
diff --git a/core/java/android/service/autofill/IAutoFillManagerService.aidl b/core/java/android/service/autofill/IAutoFillManagerService.aidl
index 2c0623413be6..a91841b98453 100644
--- a/core/java/android/service/autofill/IAutoFillManagerService.aidl
+++ b/core/java/android/service/autofill/IAutoFillManagerService.aidl
@@ -19,36 +19,20 @@ package android.service.autofill;
 import android.os.Bundle;
 
 /**
- * Intermediator between apps being auto-filled and auto-fill service implementations.
+ * Mediator between apps being auto-filled and auto-fill service implementations.
  *
  * {@hide}
  */
 interface IAutoFillManagerService {
 
     /**
-     * Starts an auto-fill session for the top activities for a given user.
-     *
-     * It's used to start a new session from system affordances.
+     * Request auto-fill on the top activity of a given user.
      *
      * @param userId user handle.
-     * @param args the bundle to pass as arguments to the voice interaction session.
-     * @param flags flags indicating optional session behavior.
      * @param activityToken optional token of activity that needs to be on top.
      *
-     * @return session token, or null if session was not created (for example, if the activity's
-     *         user does not have an auto-fill service associated with).
-     */
-     // TODO: pass callback providing an onAutoFill() method
-    String startSession(int userId, in Bundle args, int flags, IBinder activityToken);
-
-    /**
-     * Finishes an auto-fill session.
-     *
-     * @param userId user handle.
-     * @param token session token.
-     *
-     * @return true if session existed and was finished.
+     * @return whether the request succeeded  (for example, if the activity's
+     *         user does not have an auto-fill service associated with, it will return false).
      */
-    boolean finishSession(int userId, String token);
-
+    boolean requestAutoFill(int userId, IBinder activityToken);
 }
diff --git a/core/java/android/service/autofill/IAutoFillService.aidl b/core/java/android/service/autofill/IAutoFillService.aidl
index 73d8d5db5004..dca3c700c0a9 100644
--- a/core/java/android/service/autofill/IAutoFillService.aidl
+++ b/core/java/android/service/autofill/IAutoFillService.aidl
@@ -16,15 +16,17 @@
 
 package android.service.autofill;
 
-import android.os.Bundle;
 import android.app.assist.AssistStructure;
+import android.os.Bundle;
+import android.service.autofill.IAutoFillCallback;
+import com.android.internal.os.IResultReceiver;
 
 /**
  * @hide
  */
-oneway interface IAutoFillService {
+interface IAutoFillService {
+    // TODO: rename to onConnected() / onDisconnected()
     void ready();
-    void newSession(String token, in Bundle data, int flags, in AssistStructure structure);
-    void finishSession(String token);
     void shutdown();
+    IResultReceiver getAssistReceiver();
 }
diff --git a/core/java/android/service/voice/VoiceInteractionSession.java b/core/java/android/service/voice/VoiceInteractionSession.java
index e9bbc2de26cc..12aed251904f 100644
--- a/core/java/android/service/voice/VoiceInteractionSession.java
+++ b/core/java/android/service/voice/VoiceInteractionSession.java
@@ -119,6 +119,8 @@ public class VoiceInteractionSession implements KeyEvent.Callback, ComponentCall
     public static final String KEY_CONTENT = "content";
     /** @hide */
     public static final String KEY_RECEIVER_EXTRAS = "receiverExtras";
+    /** @hide */
+    public static final String KEY_AUTO_FILL_CALLBACK = "autoFillCallback";
 
     final Context mContext;
     final HandlerCaller mHandlerCaller;
diff --git a/core/java/android/view/View.java b/core/java/android/view/View.java
index 441f3302994f..02a85216cc20 100644
--- a/core/java/android/view/View.java
+++ b/core/java/android/view/View.java
@@ -6703,6 +6703,11 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
         } else {
             structure.setId(id, null, null, null);
         }
+
+        // The auto-fill id needs to be unique, but its value doesn't matter, so it's better to
+        // reuse the accessibility id to save space.
+        structure.setAutoFillId(getAccessibilityViewId());
+
         structure.setDimens(mLeft, mTop, mScrollX, mScrollY, mRight - mLeft, mBottom - mTop);
         if (!hasIdentityMatrix()) {
             structure.setTransformation(getMatrix());
diff --git a/core/java/android/view/ViewStructure.java b/core/java/android/view/ViewStructure.java
index 2e4ba74159f9..e9ff9d0edba6 100644
--- a/core/java/android/view/ViewStructure.java
+++ b/core/java/android/view/ViewStructure.java
@@ -275,4 +275,7 @@ public abstract class ViewStructure {
 
     /** @hide */
     public abstract Rect getTempRect();
+
+    /** @hide */
+    public abstract void setAutoFillId(int autoFillId);
 }