Replace Voice class with VoiceController

Bug: 29538369

The static Voice class is now implemented as a delegate controller behind
the Controller singleton. This is a more natural location for the code and
prepares the code base for alternate implementations of the VoiceController
interface for testing purposes.

Change-Id: I0c9b669e4f47da7fb30b4b55177c039a7e8970e4

7 files changed, 187 insertions, 120 deletions

diff --git a/src/com/android/deskclock/FetchMatchingAlarmsAction.java b/src/com/android/deskclock/FetchMatchingAlarmsAction.java
index 9b797b479..667b64da4 100644
--- a/src/com/android/deskclock/FetchMatchingAlarmsAction.java
+++ b/src/com/android/deskclock/FetchMatchingAlarmsAction.java
@@ -24,6 +24,7 @@ import android.os.Looper;
 import android.provider.AlarmClock;
 
 import com.android.deskclock.alarms.AlarmStateManager;
+import com.android.deskclock.controller.Controller;
 import com.android.deskclock.provider.Alarm;
 import com.android.deskclock.provider.AlarmInstance;
 
@@ -175,6 +176,6 @@ class FetchMatchingAlarmsAction implements Runnable {
 
     private void notifyFailureAndLog(String reason, Activity activity) {
         LogUtils.e(reason);
-        Voice.notifyFailure(activity, reason);
+        Controller.getController().notifyVoiceFailure(activity, reason);
     }
 }
diff --git a/src/com/android/deskclock/HandleApiCalls.java b/src/com/android/deskclock/HandleApiCalls.java
index b4bef3a6c..8bf0aef39 100644
--- a/src/com/android/deskclock/HandleApiCalls.java
+++ b/src/com/android/deskclock/HandleApiCalls.java
@@ -32,6 +32,7 @@ import android.text.TextUtils;
 import android.text.format.DateFormat;
 
 import com.android.deskclock.alarms.AlarmStateManager;
+import com.android.deskclock.controller.Controller;
 import com.android.deskclock.data.DataModel;
 import com.android.deskclock.data.Timer;
 import com.android.deskclock.data.Weekdays;
@@ -127,7 +128,7 @@ public class HandleApiCalls extends Activity {
                 context.getContentResolver(), alarm.id);
         if (instance == null) {
             final String reason = context.getString(R.string.no_alarm_scheduled_for_this_time);
-            Voice.notifyFailure(activity, reason);
+            Controller.getController().notifyVoiceFailure(activity, reason);
             LogUtils.i(reason);
             return;
         }
@@ -152,18 +153,17 @@ public class HandleApiCalls extends Activity {
             // Otherwise the alarm cannot be dismissed at this time.
             final String reason = context.getString(
                     R.string.alarm_cant_be_dismissed_still_more_than_24_hours_away, time);
-            Voice.notifyFailure(activity, reason);
+            Controller.getController().notifyVoiceFailure(activity, reason);
             LogUtils.i(reason);
         }
 
         // Log the successful dismissal.
         final String reason = context.getString(R.string.alarm_is_dismissed, time);
         LogUtils.i(reason);
-        Voice.notifySuccess(activity, reason);
+        Controller.getController().notifyVoiceSuccess(activity, reason);
         Events.sendAlarmEvent(R.string.action_dismiss, R.string.label_intent);
     }
 
-
     private static class DismissAlarmAsync extends AsyncTask<Void, Void, Void> {
 
         private final Context mContext;
@@ -186,7 +186,7 @@ public class HandleApiCalls extends Activity {
                 if (instance == null) {
                     final String reason = mContext.getString(R.string.cannot_locate_alarm);
                     LogUtils.i(reason);
-                    Voice.notifyFailure(mActivity, reason);
+                    Controller.getController().notifyVoiceFailure(mActivity, reason);
                     return null;
                 }
 
@@ -194,14 +194,14 @@ public class HandleApiCalls extends Activity {
                 if (state == MISSED_STATE) {
                     final String reason = mContext.getString(R.string.alarm_is_already_missed);
                     LogUtils.i(reason);
-                    Voice.notifyFailure(mActivity, reason);
+                    Controller.getController().notifyVoiceFailure(mActivity, reason);
                     return null;
                 }
 
                 if (state == PREDISMISSED_STATE || state == DISMISSED_STATE) {
                     final String reason = mContext.getString(R.string.alarm_is_already_dismissed);
                     LogUtils.i(reason);
-                    Voice.notifyFailure(mActivity, reason);
+                    Controller.getController().notifyVoiceFailure(mActivity, reason);
                     return null;
                 }
 
@@ -213,7 +213,7 @@ public class HandleApiCalls extends Activity {
             if (alarms.isEmpty()) {
                 final String reason = mContext.getString(R.string.no_scheduled_alarms);
                 LogUtils.i(reason);
-                Voice.notifyFailure(mActivity, reason);
+                Controller.getController().notifyVoiceFailure(mActivity, reason);
                 return null;
             }
 
@@ -235,7 +235,8 @@ public class HandleApiCalls extends Activity {
                         .putExtra(EXTRA_ACTION, ACTION_DISMISS)
                         .putExtra(EXTRA_ALARMS, alarms.toArray(new Parcelable[alarms.size()]));
                 mContext.startActivity(pickSelectionIntent);
-                Voice.notifySuccess(mActivity, mContext.getString(R.string.pick_alarm_to_dismiss));
+                final String voiceMessage = mContext.getString(R.string.pick_alarm_to_dismiss);
+                Controller.getController().notifyVoiceSuccess(mActivity, voiceMessage);
                 return null;
             }
 
@@ -254,7 +255,8 @@ public class HandleApiCalls extends Activity {
                         .putExtra(EXTRA_ALARMS,
                                 matchingAlarms.toArray(new Parcelable[matchingAlarms.size()]));
                 mContext.startActivity(pickSelectionIntent);
-                Voice.notifySuccess(mActivity, mContext.getString(R.string.pick_alarm_to_dismiss));
+                final String voiceMessage = mContext.getString(R.string.pick_alarm_to_dismiss);
+                Controller.getController().notifyVoiceSuccess(mActivity, voiceMessage);
                 return null;
             }
 
@@ -299,7 +301,7 @@ public class HandleApiCalls extends Activity {
                 if (instance == null) {
                     final String reason = mContext.getString(R.string.cannot_locate_alarm);
                     LogUtils.i(reason);
-                    Voice.notifyFailure(mActivity, reason);
+                    Controller.getController().notifyVoiceFailure(mActivity, reason);
                     return null;
                 }
 
@@ -332,7 +334,7 @@ public class HandleApiCalls extends Activity {
 
                 final String reason = mContext.getString(failureMessageId);
                 LogUtils.i(reason);
-                Voice.notifyFailure(mActivity, reason);
+                Controller.getController().notifyVoiceFailure(mActivity, reason);
                 return null;
             }
 
@@ -341,7 +343,7 @@ public class HandleApiCalls extends Activity {
             if (alarmInstances.isEmpty()) {
                 final String reason = mContext.getString(R.string.no_firing_alarms);
                 LogUtils.i(reason);
-                Voice.notifyFailure(mActivity, reason);
+                Controller.getController().notifyVoiceFailure(mActivity, reason);
                 return null;
             }
 
@@ -359,7 +361,7 @@ public class HandleApiCalls extends Activity {
                 alarmInstance.getAlarmTime().getTime());
         final String reason = context.getString(R.string.alarm_is_snoozed, time);
         LogUtils.i(reason);
-        Voice.notifySuccess(activity, reason);
+        Controller.getController().notifyVoiceSuccess(activity, reason);
         AlarmStateManager.setSnoozeState(context, alarmInstance, true);
         LogUtils.i("Snooze %d:%d", alarmInstance.mHour, alarmInstance.mMinute);
         Events.sendAlarmEvent(R.string.action_snooze, R.string.label_intent);
@@ -376,7 +378,7 @@ public class HandleApiCalls extends Activity {
                 context.getContentResolver(), alarm.id);
         if (instance == null) {
             final String reason = context.getString(R.string.no_alarm_scheduled_for_this_time);
-            Voice.notifyFailure(activity, reason);
+            Controller.getController().notifyVoiceFailure(activity, reason);
             LogUtils.i(reason);
             return;
         }
@@ -393,7 +395,7 @@ public class HandleApiCalls extends Activity {
 
         final String reason = context.getString(R.string.alarm_is_deleted, time);
         LogUtils.i(reason);
-        Voice.notifySuccess(activity, reason);
+        Controller.getController().notifyVoiceSuccess(activity, reason);
         AlarmStateManager.deleteInstanceAndUpdateParent(context, instance);
         Events.sendAlarmEvent(R.string.action_delete, R.string.label_intent);
     }
@@ -420,7 +422,7 @@ public class HandleApiCalls extends Activity {
                 if (instance == null) {
                     final String reason = mContext.getString(R.string.cannot_locate_alarm);
                     LogUtils.i(reason);
-                    Voice.notifyFailure(mActivity, reason);
+                    Controller.getController().notifyVoiceFailure(mActivity, reason);
                     return null;
                 }
 
@@ -432,7 +434,7 @@ public class HandleApiCalls extends Activity {
             if (alarms.isEmpty()) {
                 final String reason = mContext.getString(R.string.no_alarms);
                 LogUtils.i(reason);
-                Voice.notifyFailure(mActivity, reason);
+                Controller.getController().notifyVoiceFailure(mActivity, reason);
                 return null;
             }
 
@@ -445,7 +447,8 @@ public class HandleApiCalls extends Activity {
                         .putExtra(EXTRA_ACTION, ACTION_DELETE)
                         .putExtra(EXTRA_ALARMS, alarms.toArray(new Parcelable[alarms.size()]));
                 mContext.startActivity(pickSelectionIntent);
-                Voice.notifySuccess(mActivity, mContext.getString(R.string.pick_alarm_to_delete));
+                final String voiceMessage = mContext.getString(R.string.pick_alarm_to_delete);
+                Controller.getController().notifyVoiceSuccess(mActivity, voiceMessage);
                 return null;
             }
 
@@ -465,7 +468,8 @@ public class HandleApiCalls extends Activity {
                                 .putExtra(EXTRA_ALARMS,
                                         matchingAlarms.toArray(new Parcelable[matchingAlarms.size()]));
                 mContext.startActivity(pickSelectionIntent);
-                Voice.notifySuccess(mActivity, mContext.getString(R.string.pick_alarm_to_delete));
+                final String voiceMessage = mContext.getString(R.string.pick_alarm_to_delete);
+                Controller.getController().notifyVoiceSuccess(mActivity, voiceMessage);
                 return null;
             }
 
@@ -484,7 +488,7 @@ public class HandleApiCalls extends Activity {
 
             if (!matches) {
                 final String reason = mContext.getString(R.string.no_alarm_scheduled_for_this_time);
-                Voice.notifyFailure(mActivity, reason);
+                Controller.getController().notifyVoiceFailure(mActivity, reason);
                 LogUtils.i(reason);
             }
 
@@ -507,7 +511,8 @@ public class HandleApiCalls extends Activity {
             hour = intent.getIntExtra(AlarmClock.EXTRA_HOUR, hour);
             if (hour < 0 || hour > 23) {
                 final int mins = intent.getIntExtra(AlarmClock.EXTRA_MINUTES, 0);
-                Voice.notifyFailure(this, getString(R.string.invalid_time, hour, mins, " "));
+                final String voiceMessage = getString(R.string.invalid_time, hour, mins, " ");
+                Controller.getController().notifyVoiceFailure(this, voiceMessage);
                 LogUtils.i("HandleApiCalls given illegal hour: " + hour);
                 return;
             }
@@ -516,7 +521,8 @@ public class HandleApiCalls extends Activity {
         // Validate the minute, if one was given.
         final int minutes = intent.getIntExtra(AlarmClock.EXTRA_MINUTES, 0);
         if (minutes < 0 || minutes > 59) {
-            Voice.notifyFailure(this, getString(R.string.invalid_time, hour, minutes, " "));
+            final String voiceMessage = getString(R.string.invalid_time, hour, minutes, " ");
+            Controller.getController().notifyVoiceFailure(this, voiceMessage);
             LogUtils.i("HandleApiCalls given illegal minute: " + minutes);
             return;
         }
@@ -529,7 +535,8 @@ public class HandleApiCalls extends Activity {
             // Attempt to locate the alarm via the deeplink.
             final Alarm alarm = Alarm.getAlarm(cr, deeplink);
             if (alarm == null) {
-                Voice.notifyFailure(this, getString(R.string.cannot_locate_alarm));
+                final String voiceMessage = getString(R.string.cannot_locate_alarm);
+                Controller.getController().notifyVoiceFailure(this, voiceMessage);
                 LogUtils.i(String.format("HandleApiCalls cannot locate alarm using: %s", deeplink));
                 return;
             }
@@ -549,7 +556,8 @@ public class HandleApiCalls extends Activity {
 
             final String time = DateFormat.getTimeFormat(this).format(
                     alarmInstance.getAlarmTime().getTime());
-            Voice.notifySuccess(this, getString(R.string.alarm_is_set, time));
+            final String voiceMessage = getString(R.string.alarm_is_set, time);
+            Controller.getController().notifyVoiceSuccess(this, voiceMessage);
             Events.sendAlarmEvent(R.string.action_update, R.string.label_intent);
             LogUtils.i("HandleApiCalls updated existing alarm: %s", alarm);
             return;
@@ -568,7 +576,8 @@ public class HandleApiCalls extends Activity {
 
             // Open DeskClock which is now positioned on the alarms tab.
             startActivity(createAlarm);
-            Voice.notifyFailure(this, getString(R.string.invalid_time, hour, minutes, " "));
+            final String voiceMessage = getString(R.string.invalid_time, hour, minutes, " ");
+            Controller.getController().notifyVoiceFailure(this, voiceMessage);
             LogUtils.i("HandleApiCalls not given time information; opening UI");
             return;
         }
@@ -609,7 +618,7 @@ public class HandleApiCalls extends Activity {
         Events.sendAlarmEvent(R.string.action_create, R.string.label_intent);
         final String time = DateFormat.getTimeFormat(this).format(
                 alarmInstance.getAlarmTime().getTime());
-        Voice.notifySuccess(this, getString(R.string.alarm_is_set, time));
+        Controller.getController().notifyVoiceSuccess(this, getString(R.string.alarm_is_set, time));
         LogUtils.i("HandleApiCalls created alarm: %s", alarm);
     }
 
@@ -648,7 +657,8 @@ public class HandleApiCalls extends Activity {
         // Verify that the timer length is between one second and one day.
         final long lengthMillis = SECOND_IN_MILLIS * intent.getIntExtra(AlarmClock.EXTRA_LENGTH, 0);
         if (lengthMillis < Timer.MIN_LENGTH || lengthMillis > Timer.MAX_LENGTH) {
-            Voice.notifyFailure(this, getString(R.string.invalid_timer_length));
+            final String voiceMessage = getString(R.string.invalid_timer_length);
+            Controller.getController().notifyVoiceFailure(this, voiceMessage);
             LogUtils.i("Invalid timer length requested: " + lengthMillis);
             return;
         }
@@ -676,7 +686,7 @@ public class HandleApiCalls extends Activity {
         // Start the selected timer.
         DataModel.getDataModel().startTimer(timer);
         Events.sendTimerEvent(R.string.action_start, R.string.label_intent);
-        Voice.notifySuccess(this, getString(R.string.timer_created));
+        Controller.getController().notifyVoiceSuccess(this, getString(R.string.timer_created));
 
         // If not instructed to skip the UI, display the running timer.
         if (!skipUi) {
diff --git a/src/com/android/deskclock/HandleDeskClockApiCalls.java b/src/com/android/deskclock/HandleDeskClockApiCalls.java
index 23be9b81e..0ac6670df 100644
--- a/src/com/android/deskclock/HandleDeskClockApiCalls.java
+++ b/src/com/android/deskclock/HandleDeskClockApiCalls.java
@@ -21,6 +21,7 @@ import android.content.Context;
 import android.content.Intent;
 import android.os.Bundle;
 
+import com.android.deskclock.controller.Controller;
 import com.android.deskclock.data.City;
 import com.android.deskclock.data.DataModel;
 import com.android.deskclock.data.Timer;
@@ -164,9 +165,9 @@ public class HandleDeskClockApiCalls extends Activity {
             }
 
             if (fail) {
-                Voice.notifyFailure(this, reason);
+                Controller.getController().notifyVoiceFailure(this, reason);
             } else {
-                Voice.notifySuccess(this, reason);
+                Controller.getController().notifyVoiceSuccess(this, reason);
             }
             LogUtils.i(reason);
         }
@@ -211,7 +212,7 @@ public class HandleDeskClockApiCalls extends Activity {
             }
 
             if (timer == null) {
-                Voice.notifyFailure(this, reason);
+                Controller.getController().notifyVoiceFailure(this, reason);
             } else {
                 timerId = timer.getId();
 
@@ -243,7 +244,7 @@ public class HandleDeskClockApiCalls extends Activity {
                         throw new IllegalArgumentException("unknown timer action: " + action);
                 }
 
-                Voice.notifySuccess(this, reason);
+                Controller.getController().notifyVoiceSuccess(this, reason);
             }
 
             LogUtils.i(reason);
@@ -285,7 +286,7 @@ public class HandleDeskClockApiCalls extends Activity {
             if (cityName == null) {
                 reason = getString(R.string.no_city_selected);
                 LogUtils.i(reason);
-                Voice.notifySuccess(this, reason);
+                Controller.getController().notifyVoiceSuccess(this, reason);
                 startActivity(new Intent(this, CitySelectionActivity.class)
                         .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK));
                 return;
@@ -296,7 +297,7 @@ public class HandleDeskClockApiCalls extends Activity {
             if (city == null) {
                 reason = getString(R.string.the_city_you_specified_is_not_available);
                 LogUtils.i(reason);
-                Voice.notifyFailure(this, reason);
+                Controller.getController().notifyVoiceFailure(this, reason);
                 startActivity(new Intent(this, CitySelectionActivity.class)
                         .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK));
                 return;
@@ -337,9 +338,9 @@ public class HandleDeskClockApiCalls extends Activity {
             }
 
             if (fail) {
-                Voice.notifyFailure(this, reason);
+                Controller.getController().notifyVoiceFailure(this, reason);
             } else {
-                Voice.notifySuccess(this, reason);
+                Controller.getController().notifyVoiceSuccess(this, reason);
             }
             LogUtils.i(reason);
         }
diff --git a/src/com/android/deskclock/Voice.java b/src/com/android/deskclock/Voice.java
deleted file mode 100644
index f33bbe7ab..000000000
--- a/src/com/android/deskclock/Voice.java
+++ /dev/null
@@ -1,79 +0,0 @@
-/*
- * Copyright (C) 2015 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 com.android.deskclock;
-
-import android.annotation.TargetApi;
-import android.app.Activity;
-import android.app.VoiceInteractor;
-import android.os.Build;
-
-/**
- * Notifies Voice Interactor about whether the action
- * was successful. Voice Interactor is called only if
- * the build version is post-Lollipop.
- */
-public final class Voice {
-
-    private static Delegate sDelegate = new VoiceInteractorDelegate();
-
-    private Voice() { }
-
-    public static void setDelegate(Delegate delegate) {
-        sDelegate = delegate;
-    }
-
-    public static Delegate getDelegate() {
-        return sDelegate;
-    }
-
-    public static void notifySuccess(Activity activity, String message) {
-        if (Utils.isMOrLater()) {
-            sDelegate.notifySuccess(activity.getVoiceInteractor(), message);
-        }
-    }
-
-    public static void notifyFailure(Activity activity, String message) {
-        if (Utils.isMOrLater()) {
-            sDelegate.notifyFailure(activity.getVoiceInteractor(), message);
-        }
-    }
-
-    public interface Delegate {
-        void notifySuccess(VoiceInteractor vi, String message);
-
-        void notifyFailure(VoiceInteractor vi, String message);
-    }
-
-    @TargetApi(Build.VERSION_CODES.M)
-    private static class VoiceInteractorDelegate implements Delegate {
-        @Override
-        public void notifySuccess(VoiceInteractor vi, String message) {
-            if (vi != null)  {
-                final VoiceInteractor.Prompt prompt = new VoiceInteractor.Prompt(message);
-                vi.submitRequest(new VoiceInteractor.CompleteVoiceRequest(prompt, null));
-            }
-        }
-
-        @Override
-        public void notifyFailure(VoiceInteractor vi, String message) {
-            if (vi != null)  {
-                final VoiceInteractor.Prompt prompt = new VoiceInteractor.Prompt(message);
-                vi.submitRequest(new VoiceInteractor.AbortVoiceRequest(prompt, null));
-            }
-        }
-    }
-}
\ No newline at end of file
diff --git a/src/com/android/deskclock/controller/Controller.java b/src/com/android/deskclock/controller/Controller.java
index ad15db6e4..82487e0f7 100644
--- a/src/com/android/deskclock/controller/Controller.java
+++ b/src/com/android/deskclock/controller/Controller.java
@@ -16,16 +16,27 @@
 
 package com.android.deskclock.controller;
 
+import android.app.Activity;
 import android.content.Context;
 
 import com.android.deskclock.Utils;
 
-public final class Controller {
+import static com.android.deskclock.Utils.enforceMainLooper;
+
+/**
+ * Interactions with Android framework components responsible for part of the user experience are
+ * handled via this singleton.
+ */
+public final class Controller implements VoiceController {
 
     private static final Controller sController = new Controller();
 
     private Context mContext;
 
+    /** The controller that interacts with voice interaction sessions on M+. */
+    private VoiceController mVoiceController;
+
+    /** The controller that creates and updates launcher shortcuts on N MR1+ */
     private ShortcutController mShortcutController;
 
     private Controller() {}
@@ -39,15 +50,50 @@ public final class Controller {
             throw new IllegalStateException("context has already been set");
         }
         mContext = context;
+        if (Utils.isMOrLater()) {
+            mVoiceController = new DefaultVoiceController();
+        }
         if (Utils.isNMR1OrLater()) {
             mShortcutController = new ShortcutController(mContext);
         }
     }
 
+    //
+    // Voice Interaction
+    //
+
+    /**
+     * @param voiceController the new delegate to control future voice interaction sessions
+     * @return the old delegate that controlled prior voice interaction sessions
+     */
+    public VoiceController setVoiceController(VoiceController voiceController) {
+        final VoiceController oldVoiceController = mVoiceController;
+        mVoiceController = voiceController;
+        return oldVoiceController;
+    }
+
+    @Override
+    public void notifyVoiceSuccess(Activity activity, String message) {
+        if (mVoiceController != null) {
+            mVoiceController.notifyVoiceSuccess(activity, message);
+        }
+    }
+
+    @Override
+    public void notifyVoiceFailure(Activity activity, String message) {
+        if (mVoiceController != null) {
+            mVoiceController.notifyVoiceFailure(activity, message);
+        }
+    }
+
+    //
+    // Shortcuts
+    //
+
     public void updateShortcuts() {
-        Utils.enforceMainLooper();
+        enforceMainLooper();
         if (mShortcutController != null) {
             mShortcutController.updateShortcuts();
         }
     }
-}
+}
\ No newline at end of file
diff --git a/src/com/android/deskclock/controller/DefaultVoiceController.java b/src/com/android/deskclock/controller/DefaultVoiceController.java
new file mode 100644
index 000000000..4329120b4
--- /dev/null
+++ b/src/com/android/deskclock/controller/DefaultVoiceController.java
@@ -0,0 +1,46 @@
+/*
+ * 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 com.android.deskclock.controller;
+
+import android.annotation.TargetApi;
+import android.app.Activity;
+import android.app.VoiceInteractor;
+import android.app.VoiceInteractor.AbortVoiceRequest;
+import android.app.VoiceInteractor.CompleteVoiceRequest;
+import android.app.VoiceInteractor.Prompt;
+import android.os.Build;
+
+@TargetApi(Build.VERSION_CODES.M)
+class DefaultVoiceController implements VoiceController {
+    @Override
+    public void notifyVoiceSuccess(Activity activity, String message) {
+        final VoiceInteractor voiceInteractor = activity.getVoiceInteractor();
+        if (voiceInteractor != null) {
+            final Prompt prompt = new Prompt(message);
+            voiceInteractor.submitRequest(new CompleteVoiceRequest(prompt, null));
+        }
+    }
+
+    @Override
+    public void notifyVoiceFailure(Activity activity, String message) {
+        final VoiceInteractor voiceInteractor = activity.getVoiceInteractor();
+        if (voiceInteractor != null) {
+            final Prompt prompt = new Prompt(message);
+            voiceInteractor.submitRequest(new AbortVoiceRequest(prompt, null));
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/com/android/deskclock/controller/VoiceController.java b/src/com/android/deskclock/controller/VoiceController.java
new file mode 100644
index 000000000..c4327e309
--- /dev/null
+++ b/src/com/android/deskclock/controller/VoiceController.java
@@ -0,0 +1,42 @@
+/*
+ * 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 com.android.deskclock.controller;
+
+import android.app.Activity;
+
+/**
+ * Implementations of this interface are consulted to terminate a voice interaction session.
+ */
+public interface VoiceController {
+    /**
+     * If the {@code activity} is currently hosting a voice interaction session, indicate the voice
+     * command was processed successfully.
+     *
+     * @param activity an Activity that may be hosting a voice interaction session
+     * @param message to be spoken to the user to indicate success
+     */
+    void notifyVoiceSuccess(Activity activity, String message);
+
+    /**
+     * If the {@code activity} is currently hosting a voice interaction session, indicate the voice
+     * command failed and must be aborted.
+     *
+     * @param activity an Activity that may be hosting a voice interaction session
+     * @param message to be spoken to the user to indicate failure
+     */
+    void notifyVoiceFailure(Activity activity, String message);
+}
\ No newline at end of file