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/*
* Copyright (C) 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 com.android.musicfx;
import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
import android.util.Log;
/**
* This Service provides a way for client to bind to MusicFx, so that MusicFx can run at same
* Process State (see @ProcessStateEnum) as the client.
*
* Currently, MusicFx does not run in a high priority state (often in CACHED_EMPTY) and can be
* easily killed by the LowMemoryKiller. However, its users (music apps, for example) are usually
* in a higher priority state, which means they are less likely to be killed. This can lead to
* MusicFx and its users being out of sync. To avoid this, framework side will keep record of all
* active MusicFx audio sessions, promote the procstate of MusicFx to foreground with the first
* audio session open, and remove the foreground procstate delegate with the last audio session
* close, or the last user of MusicFx is gone.
*
* MusicFx user APPs do not need to do anything.
*
*/
public class KeepAliveService extends Service {
private final String TAG = "MusicFxKeepAliveService";
// Binder given to clients with onBind() callback, the client app receive it as IBinder
// parameter of onServiceConnected which can not be used.
private final IBinder mBinder = new Binder();
@Override
public IBinder onBind(Intent intent) {
Log.i(TAG, "onBind with intent " + intent);
return mBinder;
}
}
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