| /* |
| * Copyright (C) 2021 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package androidx.window.util; |
| |
| import android.annotation.NonNull; |
| |
| import java.util.function.Consumer; |
| |
| /** |
| * Produces data through {@link DataProducer#getData} and provides a mechanism for receiving |
| * a callback when the data managed by the produces has changed. |
| * |
| * @param <T> The type of data this producer returns through {@link DataProducer#getData}. |
| */ |
| public interface DataProducer<T> { |
| /** |
| * Emits the first available data at that point in time. |
| * @param dataConsumer a {@link Consumer} that will receive one value. |
| */ |
| void getData(@NonNull Consumer<T> dataConsumer); |
| |
| /** |
| * Adds a callback to be notified when the data returned |
| * from {@link DataProducer#getData} has changed. |
| */ |
| void addDataChangedCallback(@NonNull Consumer<T> callback); |
| |
| /** Removes a callback previously added with {@link #addDataChangedCallback(Consumer)}. */ |
| void removeDataChangedCallback(@NonNull Consumer<T> callback); |
| } |