1/** 2 * @file Describe the file 3 * Copyright (c) 2023 Huawei Device Co., Ltd. 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 17import { ObservableMessage } from './Observable'; 18 19/** 20 * the interface of Observer 21 * 22 * @since 2022-09-09 23 */ 24export interface Observer { 25 /** 26 * 观察者被通知后，执行该方法实现行为 27 */ 28 onChange(message?: ObserverMessage); 29} 30 31export class ObserverMessage implements ObservableMessage { 32}