Adding a wrapper class over InputConsumer to use it in Launcher

/**

 * Copyright (C) 2019 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 com.android.systemui.shared.system;

import android.os.Looper;

import android.util.Pair;

import android.view.BatchedInputEventReceiver;

import android.view.Choreographer;

import android.view.InputChannel;

import android.view.InputEvent;

import android.view.InputEventSender;

/**

 * @see android.view.InputChannel

 */

public class InputChannelCompat {

    /**

     * Callback for receiving event callbacks

     */

    public interface InputEventListener {

        /**

         * @param ev event to be handled

         */

        void onInputEvent(InputEvent ev);

    }

    /**

     * Creates a dispatcher and receiver pair to better handle events across threads.

     */

    public static Pair<InputEventDispatcher, InputEventReceiver> createPair(String name,

            Looper looper, Choreographer choreographer, InputEventListener listener) {

        InputChannel[] channels = InputChannel.openInputChannelPair(name);

        InputEventDispatcher dispatcher = new InputEventDispatcher(channels[0], looper);

        InputEventReceiver receiver = new InputEventReceiver(channels[1], looper, choreographer,

                listener);

        return Pair.create(dispatcher, receiver);

    }

    /**

     * @see BatchedInputEventReceiver

     */

    public static class InputEventReceiver {

        private final BatchedInputEventReceiver mReceiver;

        private final InputChannel mInputChannel;

        public InputEventReceiver(InputChannel inputChannel, Looper looper,

                Choreographer choreographer, final InputEventListener listener) {

            mInputChannel = inputChannel;

            mReceiver = new BatchedInputEventReceiver(inputChannel, looper, choreographer) {

                @Override

                public void onInputEvent(InputEvent event) {

                    listener.onInputEvent(event);

                    finishInputEvent(event, true /* handled */);

                }

            };

        }

        /**

         * @see BatchedInputEventReceiver#dispose()

         */

        public void dispose() {

            mReceiver.dispose();

            mInputChannel.dispose();

        }

    }

    /**

     * @see InputEventSender

     */

    public static class InputEventDispatcher {

        private final InputChannel mInputChannel;

        private final InputEventSender mSender;

        private InputEventDispatcher(InputChannel inputChannel, Looper looper) {

            mInputChannel = inputChannel;

            mSender = new InputEventSender(inputChannel, looper) { };

        }

        /**

         * @see InputEventSender#sendInputEvent(int, InputEvent)

         */

        public void dispatch(InputEvent ev) {

            mSender.sendInputEvent(ev.getSequenceNumber(), ev);

        }

        /**

         * @see InputEventSender#dispose()

         */

        public void dispose() {

            mSender.dispose();

            mInputChannel.dispose();

        }

    }

}