NotificationCompatSideChannelService.java revision b1b21830e4dda2c931141f0843f856fe871fe7fc 
1/*
2 * Copyright (C) 2014 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.support.v4.app;
18
19import android.app.Notification;
20import android.app.Service;
21import android.content.Intent;
22import android.os.IBinder;
23import android.os.RemoteException;
24
25/**
26 * Abstract service to receive side channel notifications sent from
27 * {@link android.support.v4.app.NotificationManagerCompat}.
28 *
29 * <p>To receive side channel notifications, extend this service and register it in your
30 * android manifest with an intent filter for the BIND_SIDE_CHANNEL action.
31 * Note: you must also have an enabled
32 * {@link android.service.notification.NotificationListenerService} within your package.
33 *
34 * <p>Example AndroidManifest.xml addition:
35 * <pre>
36 * &lt;service android:name="com.example.NotificationSideChannelService"&gt;
37 *     &lt;intent-filter&gt;
38 *         &lt;action android:name="android.support.BIND_NOTIFICATION_SIDE_CHANNEL" /&gt;
39 *     &lt;/intent-filter&gt;
40 * &lt;/service&gt;</pre>
41 *
42 */
43public abstract class NotificationCompatSideChannelService extends Service {
44    @Override
45    public IBinder onBind(Intent intent) {
46        if (intent.getAction().equals(NotificationManagerCompat.ACTION_BIND_SIDE_CHANNEL)) {
47            return new NotificationSideChannelStub();
48        }
49        return null;
50    }
51
52    /**
53     * Handle a side-channel notification was posted to the service.
54     */
55    public abstract void notify(String packageName, int id, String tag, Notification notification);
56
57    /**
58     * Handle a side-channel cancelling of an already-notified notification.
59     */
60    public abstract void cancel(String packageName, int id, String tag);
61
62    /**
63     * Handle a side-channel cancelling of all notifications for the given package.
64     */
65    public abstract void cancelAll(String packageName);
66
67    private class NotificationSideChannelStub extends INotificationSideChannel.Stub {
68        @Override
69        public void notify(String packageName, int id, String tag, Notification notification)
70                throws RemoteException {
71            checkPermission(getCallingUid(), packageName);
72            long idToken = clearCallingIdentity();
73            try {
74                NotificationCompatSideChannelService.this.notify(packageName, id, tag, notification);
75            } finally {
76                restoreCallingIdentity(idToken);
77            }
78        }
79
80        @Override
81        public void cancel(String packageName, int id, String tag) throws RemoteException {
82            checkPermission(getCallingUid(), packageName);
83            long idToken = clearCallingIdentity();
84            try {
85                NotificationCompatSideChannelService.this.cancel(packageName, id, tag);
86            } finally {
87                restoreCallingIdentity(idToken);
88            }
89        }
90
91        @Override
92        public void cancelAll(String packageName) {
93            checkPermission(getCallingUid(), packageName);
94            long idToken = clearCallingIdentity();
95            try {
96                NotificationCompatSideChannelService.this.cancelAll(packageName);
97            } finally {
98                restoreCallingIdentity(idToken);
99            }
100        }
101    }
102
103    private void checkPermission(int callingUid, String packageName) {
104        for (String validPackage : getPackageManager().getPackagesForUid(callingUid)) {
105            if (validPackage.equals(packageName)) {
106                return;
107            }
108        }
109        throw new SecurityException("NotificationSideChannelService: Uid " + callingUid
110                + " is not authorized for package " + packageName);
111    }
112}
113