DataSetObservable.java revision 54b6cfa9a9e5b861a9930af873580d6dc20f773c 
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
19/**
20 * A specialization of Observable for DataSetObserver that provides methods for
21 * invoking the various callback methods of DataSetObserver.
22 */
23public class DataSetObservable extends Observable<DataSetObserver> {
24    /**
25     * Invokes onChanged on each observer. Called when the data set being observed has
26     * changed, and which when read contains the new state of the data.
27     */
28    public void notifyChanged() {
29        synchronized(mObservers) {
30            for (DataSetObserver observer : mObservers) {
31                observer.onChanged();
32            }
33        }
34    }
35
36    /**
37     * Invokes onInvalidated on each observer. Called when the data set being monitored
38     * has changed such that it is no longer valid.
39     */
40    public void notifyInvalidated() {
41        synchronized (mObservers) {
42            for (DataSetObserver observer : mObservers) {
43                observer.onInvalidated();
44            }
45        }
46    }
47}
48