Android MediaBrowserService Sample

This sample shows how to implement an audio media app that provides media library metadata and playback controls through a standard service. It exposes a simple music library through the new MediaBrowserService and provides MediaSession callbacks. This allows it to be used in Android Auto, for example. When not connected to a car, the app has a very simple UI that browses the media library and provides simple playback controls. When connected to Android Auto, the same service provides data and callback to the Android Auto UI in the same manner as it provides them to the local UI.

Introduction

To implement a MediaBrowserService, you need to:

• Extend android.service.media.MediaBrowserService, implementing the media browsing related methods onGetRoot and onLoadChildren;

• In onCreate, start a new MediaSession and call super.setSessionToken() with this MediaSession's token;

• Set a MediaSession.Callback class on the MediaSession. The callback class will receive all the user's actions, like play, pause, etc;

• Handle all the actual music playing using any method your app prefers (for example, the Android MediaPlayer class)

• Whenever it changes, update info about the playing item and the playing queue using MediaSession corresponding methods (setMetadata, setPlaybackState, setQueue, setQueueTitle, etc)

• Handle AudioManager focus change events and react appropriately (e.g. pause when audio focus is lost)

To make it compatible with Android Auto, you also need to:

• Declare a meta-data tag in AndroidManifest.xml linking to a xml resource with a automotiveApp root element. For a media app, this must include an <uses name="media"/> element as a child.

  For example, in AndroidManifest.xml:

     <meta-data android:name="com.google.android.gms.car.application"
       android:resource="@xml/automotive_app_desc"/>

And in res/xml/automotive_app_desc.xml:

      <?xml version="1.0" encoding="utf-8"?>
      <automotiveApp>
          <uses name="media"/>
      </automotiveApp>

• Declare and export the service in AndroidManifest.xml:

    <service
        android:name=".service.MusicService"
        android:exported="true">
      <intent-filter>
         <action android:name="android.media.browse.MediaBrowserService" />
      </intent-filter>
    </service>

Pre-requisites

• Android SDK v21
• Android Build Tools v21.1.1
• Android Support Repository

Screenshots

Getting Started

This sample uses the Gradle build system. To build this project, use the "gradlew build" command or use "Import Project" in Android Studio.

Support

• Google+ Community: https://plus.google.com/communities/105153134372062985968
• Stack Overflow: http://stackoverflow.com/questions/tagged/android

If you've found an error in this sample, please file an issue: https://github.com/googlesamples/android-MediaBrowserService

Patches are encouraged, and may be submitted by forking this project and submitting a pull request through GitHub. Please see CONTRIBUTING.md for more details.

License

Copyright 2014 The Android Open Source Project, Inc.

Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to you 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.