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 
17 package android.database;
18 
19 /**
20  * Receives call backs when a data set has been changed, or made invalid. The typically data sets
21  * that are observed are {@link Cursor}s or {@link android.widget.Adapter}s.
22  * DataSetObserver must be implemented by objects which are added to a DataSetObservable.
23  */
24 public abstract class DataSetObserver {
25     /**
26      * This method is called when the entire data set has changed,
27      * most likely through a call to {@link Cursor#requery()} on a {@link Cursor}.
28      */
onChanged()29     public void onChanged() {
30         // Do nothing
31     }
32 
33     /**
34      * This method is called when the entire data becomes invalid,
35      * most likely through a call to {@link Cursor#deactivate()} or {@link Cursor#close()} on a
36      * {@link Cursor}.
37      */
onInvalidated()38     public void onInvalidated() {
39         // Do nothing
40     }
41 }
42