/*
 * Copyright 2022 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;

/**
 * Callback for an evaluation result. This is intended to support two-step updates; first a
 * notification will be sent that the evaluation result item will be updated, then the new
 * evaluation result will be delivered. This allows downstream consumers to properly synchronize
 * their updates if they depend on two or more evaluation result items, rather than updating
 * multiple times (with potentially invalid states).
 *
 * @param <T> Data type.
 */
public interface DynamicTypeValueReceiver<T> {
    /**
     * Called when the dynamic type that this callback was registered for has a new evaluation
     * result.
     */
    void onData(@NonNull T newData);

    /** Called when the dynamic type that this callback was registered for has an invalid result. */
    void onInvalidated();
}