1/*
2 * Copyright (C) 2007 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.database;
18
19import android.net.Uri;
20
21/**
22 * A specialization of {@link Observable} for {@link ContentObserver}
23 * that provides methods for sending notifications to a list of
24 * {@link ContentObserver} objects.
25 */
26public class ContentObservable extends Observable<ContentObserver> {
27    // Even though the generic method defined in Observable would be perfectly
28    // fine on its own, we can't delete this overridden method because it would
29    // potentially break binary compatibility with existing applications.
30    @Override
31    public void registerObserver(ContentObserver observer) {
32        super.registerObserver(observer);
33    }
34
35    /**
36     * Invokes {@link ContentObserver#dispatchChange(boolean)} on each observer.
37     * <p>
38     * If <code>selfChange</code> is true, only delivers the notification
39     * to the observer if it has indicated that it wants to receive self-change
40     * notifications by implementing {@link ContentObserver#deliverSelfNotifications}
41     * to return true.
42     * </p>
43     *
44     * @param selfChange True if this is a self-change notification.
45     *
46     * @deprecated Use {@link #dispatchChange(boolean, Uri)} instead.
47     */
48    @Deprecated
49    public void dispatchChange(boolean selfChange) {
50        dispatchChange(selfChange, null);
51    }
52
53    /**
54     * Invokes {@link ContentObserver#dispatchChange(boolean, Uri)} on each observer.
55     * Includes the changed content Uri when available.
56     * <p>
57     * If <code>selfChange</code> is true, only delivers the notification
58     * to the observer if it has indicated that it wants to receive self-change
59     * notifications by implementing {@link ContentObserver#deliverSelfNotifications}
60     * to return true.
61     * </p>
62     *
63     * @param selfChange True if this is a self-change notification.
64     * @param uri The Uri of the changed content, or null if unknown.
65     */
66    public void dispatchChange(boolean selfChange, Uri uri) {
67        synchronized(mObservers) {
68            for (ContentObserver observer : mObservers) {
69                if (!selfChange || observer.deliverSelfNotifications()) {
70                    observer.dispatchChange(selfChange, uri);
71                }
72            }
73        }
74    }
75
76    /**
77     * Invokes {@link ContentObserver#onChange} on each observer.
78     *
79     * @param selfChange True if this is a self-change notification.
80     *
81     * @deprecated Use {@link #dispatchChange} instead.
82     */
83    @Deprecated
84    public void notifyChange(boolean selfChange) {
85        synchronized(mObservers) {
86            for (ContentObserver observer : mObservers) {
87                observer.onChange(selfChange, null);
88            }
89        }
90    }
91}
92