NotificationAssistantService.java revision 3aa5f1eec08e6c3233f13935ea45c833433a2d27 
1/*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.service.notification;
18
19import android.annotation.SdkConstant;
20import android.content.Context;
21import android.content.Intent;
22import android.os.Handler;
23import android.os.IBinder;
24import android.os.Looper;
25import android.os.Message;
26import android.os.RemoteException;
27import android.util.Log;
28import com.android.internal.os.SomeArgs;
29
30import java.util.List;
31
32/**
33 * A service that helps the user manage notifications.
34 */
35public abstract class NotificationAssistantService extends NotificationListenerService {
36    private static final String TAG = "NotificationAssistants";
37
38    /**
39     * The {@link Intent} that must be declared as handled by the service.
40     */
41    @SdkConstant(SdkConstant.SdkConstantType.SERVICE_ACTION)
42    public static final String SERVICE_INTERFACE
43            = "android.service.notification.NotificationAssistantService";
44
45    private Handler mHandler;
46
47    @Override
48    protected void attachBaseContext(Context base) {
49        super.attachBaseContext(base);
50        mHandler = new MyHandler(getContext().getMainLooper());
51    }
52
53    @Override
54    public final IBinder onBind(Intent intent) {
55        if (mWrapper == null) {
56            mWrapper = new NotificationAssistantServiceWrapper();
57        }
58        return mWrapper;
59    }
60
61    /**
62     * A notification was posted by an app. Called before alert.
63     *
64     * @param sbn the new notification
65     * @param importance the initial importance of the notification.
66     * @param user true if the initial importance reflects an explicit user preference.
67     * @return an adjustment or null to take no action, within 100ms.
68     */
69    abstract public Adjustment onNotificationEnqueued(StatusBarNotification sbn,
70          int importance, boolean user);
71
72    /**
73     * Updates a notification.  N.B. this won’t cause
74     * an existing notification to alert, but might allow a future update to
75     * this notification to alert.
76     *
77     * @param adjustment the adjustment with an explanation
78     */
79    public final void adjustNotification(Adjustment adjustment) {
80        if (!isBound()) return;
81        try {
82            getNotificationInterface().applyAdjustmentFromAssistantService(mWrapper, adjustment);
83        } catch (android.os.RemoteException ex) {
84            Log.v(TAG, "Unable to contact notification manager", ex);
85        }
86    }
87
88    /**
89     * Updates existing notifications. Re-ranking won't occur until all adjustments are applied.
90     * N.B. this won’t cause an existing notification to alert, but might allow a future update to
91     * these notifications to alert.
92     *
93     * @param adjustments a list of adjustments with explanations
94     */
95    public final void adjustNotifications(List<Adjustment> adjustments) {
96        if (!isBound()) return;
97        try {
98            getNotificationInterface().applyAdjustmentsFromAssistantService(mWrapper, adjustments);
99        } catch (android.os.RemoteException ex) {
100            Log.v(TAG, "Unable to contact notification manager", ex);
101        }
102    }
103
104    private class NotificationAssistantServiceWrapper extends NotificationListenerWrapper {
105        @Override
106        public void onNotificationEnqueued(IStatusBarNotificationHolder sbnHolder,
107                int importance, boolean user) {
108            StatusBarNotification sbn;
109            try {
110                sbn = sbnHolder.get();
111            } catch (RemoteException e) {
112                Log.w(TAG, "onNotificationEnqueued: Error receiving StatusBarNotification", e);
113                return;
114            }
115
116            SomeArgs args = SomeArgs.obtain();
117            args.arg1 = sbn;
118            args.argi1 = importance;
119            args.argi2 = user ? 1 : 0;
120            mHandler.obtainMessage(MyHandler.MSG_ON_NOTIFICATION_ENQUEUED,
121                    args).sendToTarget();
122        }
123    }
124
125    private final class MyHandler extends Handler {
126        public static final int MSG_ON_NOTIFICATION_ENQUEUED = 1;
127
128        public MyHandler(Looper looper) {
129            super(looper, null, false);
130        }
131
132        @Override
133        public void handleMessage(Message msg) {
134            switch (msg.what) {
135                case MSG_ON_NOTIFICATION_ENQUEUED: {
136                    SomeArgs args = (SomeArgs) msg.obj;
137                    StatusBarNotification sbn = (StatusBarNotification) args.arg1;
138                    final int importance = args.argi1;
139                    final boolean user = args.argi2 == 1;
140                    args.recycle();
141                    Adjustment adjustment = onNotificationEnqueued(sbn, importance, user);
142                    if (adjustment != null) {
143                        adjustNotification(adjustment);
144                    }
145                } break;
146            }
147        }
148    }
149}
150