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