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 17 package android.databinding; 18 19 /** 20 * A convenience class that implements {@link android.databinding.Observable} interface and provides 21 * {@link #notifyPropertyChanged(int)} and {@link #notifyChange} methods. 22 */ 23 public class BaseObservable implements Observable { 24 private transient PropertyChangeRegistry mCallbacks; 25 26 public BaseObservable() { 27 } 28 29 @Override 30 public synchronized void addOnPropertyChangedCallback(OnPropertyChangedCallback callback) { 31 if (mCallbacks == null) { 32 mCallbacks = new PropertyChangeRegistry(); 33 } 34 mCallbacks.add(callback); 35 } 36 37 @Override 38 public synchronized void removeOnPropertyChangedCallback(OnPropertyChangedCallback callback) { 39 if (mCallbacks != null) { 40 mCallbacks.remove(callback); 41 } 42 } 43 44 /** 45 * Notifies listeners that all properties of this instance have changed. 46 */ 47 public synchronized void notifyChange() { 48 if (mCallbacks != null) { 49 mCallbacks.notifyCallbacks(this, 0, null); 50 } 51 } 52 53 /** 54 * Notifies listeners that a specific property has changed. The getter for the property 55 * that changes should be marked with {@link Bindable} to generate a field in 56 * <code>BR</code> to be used as <code>fieldId</code>. 57 * 58 * @param fieldId The generated BR id for the Bindable field. 59 */ 60 public void notifyPropertyChanged(int fieldId) { 61 if (mCallbacks != null) { 62 mCallbacks.notifyCallbacks(this, fieldId, null); 63 } 64 } 65 } 66
