10fbfc30aSopenharmony_ci/**
20fbfc30aSopenharmony_ci * @file Describe the file
30fbfc30aSopenharmony_ci * Copyright (c) 2023 Huawei Device Co., Ltd.
40fbfc30aSopenharmony_ci * Licensed under the Apache License, Version 2.0 (the "License");
50fbfc30aSopenharmony_ci * you may not use this file except in compliance with the License.
60fbfc30aSopenharmony_ci * You may obtain a copy of the License at
70fbfc30aSopenharmony_ci *
80fbfc30aSopenharmony_ci *     http://www.apache.org/licenses/LICENSE-2.0
90fbfc30aSopenharmony_ci *
100fbfc30aSopenharmony_ci * Unless required by applicable law or agreed to in writing, software
110fbfc30aSopenharmony_ci * distributed under the License is distributed on an "AS IS" BASIS,
120fbfc30aSopenharmony_ci * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
130fbfc30aSopenharmony_ci * See the License for the specific language governing permissions and
140fbfc30aSopenharmony_ci * limitations under the License.
150fbfc30aSopenharmony_ci */
160fbfc30aSopenharmony_ci
170fbfc30aSopenharmony_ciimport { ObservableMessage } from './Observable';
180fbfc30aSopenharmony_ci
190fbfc30aSopenharmony_ci/**
200fbfc30aSopenharmony_ci * the interface of Observer
210fbfc30aSopenharmony_ci *
220fbfc30aSopenharmony_ci * @since 2022-09-09
230fbfc30aSopenharmony_ci */
240fbfc30aSopenharmony_ciexport interface Observer {
250fbfc30aSopenharmony_ci  /**
260fbfc30aSopenharmony_ci   * 观察者被通知后，执行该方法实现行为
270fbfc30aSopenharmony_ci   */
280fbfc30aSopenharmony_ci  onChange(message?: ObserverMessage);
290fbfc30aSopenharmony_ci}
300fbfc30aSopenharmony_ci
310fbfc30aSopenharmony_ciexport class ObserverMessage implements ObservableMessage {
320fbfc30aSopenharmony_ci}