ui/android/java/src/org/chromium/ui/modelutil/ForwardingListObservable.java

// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
package org.chromium.ui.modelutil;

import androidx.annotation.Nullable;

/**
 * Helper class for implementing a {@link ListObserver} that just forwards to its own observers.
 *
 * @param <P> The payload type for partial updates, or {@link Void} if the class doesn't support
 *     partial updates. TODO(bauerb): Remove this class if it turns out we can shortcut
 *     notifications
 */
public class ForwardingListObservable<P> extends ListObservableImpl<P>
        implements ListObservable.ListObserver<P> {
    @Override
    public void onItemRangeInserted(ListObservable source, int index, int count) {
        notifyItemRangeInserted(index, count);
    }

    @Override
    public void onItemRangeRemoved(ListObservable source, int index, int count) {
        notifyItemRangeRemoved(index, count);
    }

    @Override
    public void onItemRangeChanged(
            ListObservable<P> source, int index, int count, @Nullable P payload) {
        notifyItemRangeChanged(index, count, payload);
    }

    @Override
    public void onItemMoved(ListObservable source, int fromIndex, int toIndex) {
        notifyItemMoved(fromIndex, toIndex);
    }
}