DataStore.java
/*
* Copyright 2023 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.wear.protolayout.expression.pipeline;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.wear.protolayout.expression.DynamicDataKey;
import androidx.wear.protolayout.expression.proto.DynamicDataProto.DynamicDataValue;
/**
* {@link DynamicDataKey} to {@link DynamicDataValue} storage for ProtoLayout, which also supports
* sending callback when data items change.
*/
abstract class DataStore {
/**
* Registers the given callback for updates to the data item for the given {@code key}.
*
* <p>Note that the callback will be executed on the UI thread.
*/
abstract void registerCallback(
@NonNull DynamicDataKey<?> key,
@NonNull DynamicTypeValueReceiverWithPreUpdate<DynamicDataValue> callback);
/** Unregisters the callback for the given {@code key} from receiving the updates. */
abstract void unregisterCallback(
@NonNull DynamicDataKey<?> key,
@NonNull DynamicTypeValueReceiverWithPreUpdate<DynamicDataValue> callback);
/**
* Retrieve the {@link DynamicDataValue} associated with the given {@link DynamicDataKey} in
* the store.
*/
@Nullable
abstract DynamicDataValue getDynamicDataValuesProto(@NonNull DynamicDataKey<?> key);
}