我之前曾经问过类似的问题，但他们都没有帮助我。我正在构建一个音乐播放器，我希望通过我的音乐播放器连接我的音乐，如播放，暂停等。目前，媒体播放器服务与播放列表活动相关但我自定义设计我的媒体播放器，我无法连接它到服务类。
我的MusicPlayer活动是这样的：
public class MusicPlayer extends AppCompatActivity implements PlaylistFragment.OnFragmentInteractionListener{
public static final String Broadcast_PLAY_NEW_AUDIO = "com.example.anuj.musicmetest.PlayNewAudio";
ImageView buttonPlayToggle;
MediaPlayer mediaPlayer;
MediaPlayerService player;
boolean serviceBound = false;
private ServiceConnection serviceConnection = new ServiceConnection() {
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
MediaPlayerService.LocalBinder binder = (MediaPlayerService.LocalBinder) service;
player = binder.getService();
serviceBound = true;
}
@Override
public void onServiceDisconnected(ComponentName name) {
serviceBound = false;
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_player);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setTitle("Music Player");
buttonPlayToggle = (ImageView) findViewById(R.id.button_play_toggle);
buttonPlayToggle.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if(mediaPlayer == null) return;
if (mediaPlayer.isPlaying()) {
updatePlayToggle(true);
mediaPlayer.pause();
} else {
updatePlayToggle(false);
mediaPlayer.start();
}
}
});
if (!serviceBound) {
Intent playerIntent = new Intent(this, MediaPlayerService.class);
startService(playerIntent);
bindService(playerIntent, serviceConnection, Context.BIND_AUTO_CREATE);
} else {
Intent broadcastIntent = new Intent(Broadcast_PLAY_NEW_AUDIO);
sendBroadcast(broadcastIntent);
}
}
public void updatePlayToggle(boolean play) {
buttonPlayToggle.setImageResource(play ? R.drawable.ic_pause : R.drawable.ic_play);
}
我的ServicecClass是这样的：
public class MediaPlayerService extends Service implements MediaPlayer.OnCompletionListener,
MediaPlayer.OnPreparedListener, MediaPlayer.OnErrorListener, MediaPlayer.OnSeekCompleteListener,
MediaPlayer.OnInfoListener, MediaPlayer.OnBufferingUpdateListener,
AudioManager.OnAudioFocusChangeListener {
public static final String ACTION_PLAY = "com.example.anuj.musicmetest.ACTION_PLAY";
public static final String ACTION_PAUSE = "com.example.anuj.musicmetest.ACTION_PAUSE";
public static final String ACTION_PREVIOUS = "com.example.anuj.musicmetest.ACTION_PREVIOUS";
public static final String ACTION_NEXT = "com.example.anuj.musicmetest.ACTION_NEXT";
public static final String ACTION_STOP = "com.example.anuj.musicmetest.ACTION_STOP";
private MediaPlayer mediaPlayer;
private MediaSessionManager mediaSessionManager;
private MediaSessionCompat mediaSession;
private MediaControllerCompat.TransportControls transportControls;
private static final int NOTIFICATION_ID = 101;
//Used to pause/resume MediaPlayer
private int resumePosition;
//AudioFocus
private AudioManager audioManager;
// Binder given to clients
private final IBinder iBinder = new LocalBinder();
private ArrayList<Audio> audioList;
private int audioIndex = -1;
private Audio activeAudio; //an object on the currently playing audio
//Handle incoming phone calls
private boolean ongoingCall = false;
private PhoneStateListener phoneStateListener;
private TelephonyManager telephonyManager;
/**
* Service lifecycle methods
*/
@Override
public IBinder onBind(Intent intent) {
return iBinder;
}
@Override
public void onCreate() {
super.onCreate();
callStateListener();
//ACTION_AUDIO_BECOMING_NOISY -- change in audio outputs -- BroadcastReceiver
registerBecomingNoisyReceiver();
//Listen for new Audio to play -- BroadcastReceiver
register_playNewAudio();
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
try {
//Load data from SharedPreferences
StorageUtil storage = new StorageUtil(getApplicationContext());
audioList = storage.loadAudio();
audioIndex = storage.loadAudioIndex();
if (audioIndex != -1 && audioIndex < audioList.size()) {
//index is in a valid range
activeAudio = audioList.get(audioIndex);
} else {
stopSelf();
}
} catch (NullPointerException e) {
stopSelf();
}
//Request audio focus
if (!requestAudioFocus()) {
//Could not gain focus
stopSelf();
}
if (mediaSessionManager == null) {
try {
initMediaSession();
initMediaPlayer();
} catch (RemoteException e) {
e.printStackTrace();
stopSelf();
}
buildNotification(PlaybackStatus.PLAYING);
}
//Handle Intent action from MediaSession.TransportControls
handleIncomingActions(intent);
return super.onStartCommand(intent, flags, startId);
}
@Override
public boolean onUnbind(Intent intent) {
mediaSession.release();
removeNotification();
return super.onUnbind(intent);
}
@Override
public void onDestroy() {
super.onDestroy();
if (mediaPlayer != null) {
stopMedia();
mediaPlayer.release();
}
removeAudioFocus();
//Disable the PhoneStateListener
if (phoneStateListener != null) {
telephonyManager.listen(phoneStateListener, PhoneStateListener.LISTEN_NONE);
}
removeNotification();
//unregister BroadcastReceivers
unregisterReceiver(becomingNoisyReceiver);
unregisterReceiver(playNewAudio);
//clear cached playlist
new StorageUtil(getApplicationContext()).clearCachedAudioPlaylist();
}
/**
* Service Binder
*/
public class LocalBinder extends Binder {
public MediaPlayerService getService() {
// Return this instance of LocalService so clients can call public methods
return MediaPlayerService.this;
}
}
/**
* MediaPlayer callback methods
*/
@Override
public void onBufferingUpdate(MediaPlayer mp, int percent) {
//Invoked indicating buffering status of
//a media resource being streamed over the network.
}
@Override
public void onCompletion(MediaPlayer mp) {
//Invoked when playback of a media source has completed.
stopMedia();
removeNotification();
//stop the service
stopSelf();
}
@Override
public boolean onError(MediaPlayer mp, int what, int extra) {
//Invoked when there has been an error during an asynchronous operation
switch (what) {
case MediaPlayer.MEDIA_ERROR_NOT_VALID_FOR_PROGRESSIVE_PLAYBACK:
Log.d("MediaPlayer Error", "MEDIA ERROR NOT VALID FOR PROGRESSIVE PLAYBACK " + extra);
break;
case MediaPlayer.MEDIA_ERROR_SERVER_DIED:
Log.d("MediaPlayer Error", "MEDIA ERROR SERVER DIED " + extra);
break;
case MediaPlayer.MEDIA_ERROR_UNKNOWN:
Log.d("MediaPlayer Error", "MEDIA ERROR UNKNOWN " + extra);
break;
}
return false;
}
@Override
public boolean onInfo(MediaPlayer mp, int what, int extra) {
//Invoked to communicate some info
return false;
}
@Override
public void onPrepared(MediaPlayer mp) {
//Invoked when the media source is ready for playback.
playMedia();
}
@Override
public void onSeekComplete(MediaPlayer mp) {
//Invoked indicating the completion of a seek operation.
}
@Override
public void onAudioFocusChange(int focusState) {
//Invoked when the audio focus of the system is updated.
switch (focusState) {
case AudioManager.AUDIOFOCUS_GAIN:
// resume playback
if (mediaPlayer == null) initMediaPlayer();
else if (!mediaPlayer.isPlaying()) mediaPlayer.start();
mediaPlayer.setVolume(1.0f, 1.0f);
break;
case AudioManager.AUDIOFOCUS_LOSS:
// Lost focus for an unbounded amount of time: stop playback and release media player
if (mediaPlayer.isPlaying()) mediaPlayer.stop();
mediaPlayer.release();
mediaPlayer = null;
break;
case AudioManager.AUDIOFOCUS_LOSS_TRANSIENT:
if (mediaPlayer.isPlaying()) mediaPlayer.pause();
break;
case AudioManager.AUDIOFOCUS_LOSS_TRANSIENT_CAN_DUCK:
// Lost focus for a short time, but it's ok to keep playing
// at an attenuated level
if (mediaPlayer.isPlaying()) mediaPlayer.setVolume(0.1f, 0.1f);
break;
}
}
/**
* AudioFocus
*/
private boolean requestAudioFocus() {
audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
int result = audioManager.requestAudioFocus(this, AudioManager.STREAM_MUSIC, AudioManager.AUDIOFOCUS_GAIN);
if (result == AudioManager.AUDIOFOCUS_REQUEST_GRANTED) {
//Focus gained
return true;
}
//Could not gain focus
return false;
}
private boolean removeAudioFocus() {
return AudioManager.AUDIOFOCUS_REQUEST_GRANTED ==
audioManager.abandonAudioFocus(this);
}
/**
* MediaPlayer actions
*/
private void initMediaPlayer() {
if (mediaPlayer == null)
mediaPlayer = new MediaPlayer();//new MediaPlayer instance
//Set up MediaPlayer event listeners
mediaPlayer.setOnCompletionListener(this);
mediaPlayer.setOnErrorListener(this);
mediaPlayer.setOnPreparedListener(this);
mediaPlayer.setOnBufferingUpdateListener(this);
mediaPlayer.setOnSeekCompleteListener(this);
mediaPlayer.setOnInfoListener(this);
//Reset so that the MediaPlayer is not pointing to another data source
mediaPlayer.reset();
mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
try {
// Set the data source to the mediaFile location
mediaPlayer.setDataSource(activeAudio.getLocalData());
} catch (IOException e) {
e.printStackTrace();
stopSelf();
}
mediaPlayer.prepareAsync();
}
private void playMedia() {
if (!mediaPlayer.isPlaying()) {
mediaPlayer.start();
}
}
private void stopMedia() {
if (mediaPlayer == null) return;
if (mediaPlayer.isPlaying()) {
mediaPlayer.stop();
}
}
private void pauseMedia() {
if (mediaPlayer.isPlaying()) {
mediaPlayer.pause();
resumePosition = mediaPlayer.getCurrentPosition();
}
}
private void resumeMedia() {
if (!mediaPlayer.isPlaying()) {
mediaPlayer.seekTo(resumePosition);
mediaPlayer.start();
}
}
private void skipToNext() {
if (audioIndex == audioList.size() - 1) {
//if last in playlist
audioIndex = 0;
activeAudio = audioList.get(audioIndex);
} else {
//get next in playlist
activeAudio = audioList.get(++audioIndex);
}
//Update stored index
new StorageUtil(getApplicationContext()).storeAudioIndex(audioIndex);
stopMedia();
//reset mediaPlayer
mediaPlayer.reset();
initMediaPlayer();
}
private void skipToPrevious() {
if (audioIndex == 0) {
//if first in playlist
//set index to the last of audioList
audioIndex = audioList.size() - 1;
activeAudio = audioList.get(audioIndex);
} else {
//get previous in playlist
activeAudio = audioList.get(--audioIndex);
}
//Update stored index
new StorageUtil(getApplicationContext()).storeAudioIndex(audioIndex);
stopMedia();
//reset mediaPlayer
mediaPlayer.reset();
initMediaPlayer();
}
/**
* ACTION_AUDIO_BECOMING_NOISY -- change in audio outputs
*/
private BroadcastReceiver becomingNoisyReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
//pause audio on ACTION_AUDIO_BECOMING_NOISY
pauseMedia();
buildNotification(PlaybackStatus.PAUSED);
}
};
private void registerBecomingNoisyReceiver() {
//register after getting audio focus
IntentFilter intentFilter = new IntentFilter(AudioManager.ACTION_AUDIO_BECOMING_NOISY);
registerReceiver(becomingNoisyReceiver, intentFilter);
}
/**
* Handle PhoneState changes
*/
private void callStateListener() {
// Get the telephony manager
telephonyManager = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
//Starting listening for PhoneState changes
phoneStateListener = new PhoneStateListener() {
@Override
public void onCallStateChanged(int state, String incomingNumber) {
switch (state) {
//if at least one call exists or the phone is ringing
//pause the MediaPlayer
case TelephonyManager.CALL_STATE_OFFHOOK:
case TelephonyManager.CALL_STATE_RINGING:
if (mediaPlayer != null) {
pauseMedia();
ongoingCall = true;
}
break;
case TelephonyManager.CALL_STATE_IDLE:
// Phone idle. Start playing.
if (mediaPlayer != null) {
if (ongoingCall) {
ongoingCall = false;
resumeMedia();
}
}
break;
}
}
};
// Register the listener with the telephony manager
// Listen for changes to the device call state.
telephonyManager.listen(phoneStateListener,
PhoneStateListener.LISTEN_CALL_STATE);
}
/**
* MediaSession and Notification actions
*/
private void initMediaSession() throws RemoteException {
if (mediaSessionManager != null) return; //mediaSessionManager exists
mediaSessionManager = (MediaSessionManager) getSystemService(Context.MEDIA_SESSION_SERVICE);
// Create a new MediaSession
mediaSession = new MediaSessionCompat(getApplicationContext(), "AudioPlayer");
//Get MediaSessions transport controls
transportControls = mediaSession.getController().getTransportControls();
//set MediaSession -> ready to receive media commands
mediaSession.setActive(true);
//indicate that the MediaSession handles transport control commands
// through its MediaSessionCompat.Callback.
mediaSession.setFlags(MediaSessionCompat.FLAG_HANDLES_TRANSPORT_CONTROLS);
//Set mediaSession's MetaData
updateMetaData();
// Attach Callback to receive MediaSession updates
mediaSession.setCallback(new MediaSessionCompat.Callback() {
// Implement callbacks
@Override
public void onPlay() {
super.onPlay();
resumeMedia();
buildNotification(PlaybackStatus.PLAYING);
}
@Override
public void onPause() {
super.onPause();
pauseMedia();
buildNotification(PlaybackStatus.PAUSED);
}
@Override
public void onSkipToNext() {
super.onSkipToNext();
skipToNext();
updateMetaData();
buildNotification(PlaybackStatus.PLAYING);
}
@Override
public void onSkipToPrevious() {
super.onSkipToPrevious();
skipToPrevious();
updateMetaData();
buildNotification(PlaybackStatus.PLAYING);
}
@Override
public void onStop() {
super.onStop();
removeNotification();
//Stop the service
stopSelf();
}
@Override
public void onSeekTo(long position) {
super.onSeekTo(position);
}
});
}
private void updateMetaData() {
mediaSession.setMetadata(new MediaMetadataCompat.Builder()
.putString(MediaMetadataCompat.METADATA_KEY_ARTIST, activeAudio.getLocalArtist())
.putString(MediaMetadataCompat.METADATA_KEY_ALBUM, activeAudio.getLocalAlbum())
.putString(MediaMetadataCompat.METADATA_KEY_TITLE, activeAudio.getLocalTitle())
.build());
}
private void buildNotification(PlaybackStatus playbackStatus) {
int notificationAction = android.R.drawable.ic_media_pause;//needs to be initialized
PendingIntent play_pauseAction = null;
//Build a new notification according to the current state of the MediaPlayer
if (playbackStatus == PlaybackStatus.PLAYING) {
notificationAction = android.R.drawable.ic_media_pause;
//create the pause action
play_pauseAction = playbackAction(1);
} else if (playbackStatus == PlaybackStatus.PAUSED) {
notificationAction = android.R.drawable.ic_media_play;
//create the play action
play_pauseAction = playbackAction(0);
}
// Create a new Notification
NotificationCompat.Builder notificationBuilder = (NotificationCompat.Builder) new NotificationCompat.Builder(this)
// Hide the timestamp
.setShowWhen(false)
// Set the Notification style
.setStyle(new NotificationCompat.MediaStyle()
// Attach our MediaSession token
.setMediaSession(mediaSession.getSessionToken())
// Show our playback controls in the compat view
.setShowActionsInCompactView(0, 1, 2))
// Set the Notification color
.setColor(getResources().getColor(R.color.colorAccent))
// Set the large and small icons
.setSmallIcon(android.R.drawable.stat_sys_headset)
// Set Notification content information
.setContentText(activeAudio.getLocalArtist())
.setContentTitle(activeAudio.getLocalAlbum())
.setContentInfo(activeAudio.getLocalTitle())
// Add playback actions
.addAction(android.R.drawable.ic_media_previous, "previous", playbackAction(3))
.addAction(notificationAction, "pause", play_pauseAction)
.addAction(android.R.drawable.ic_media_next, "next", playbackAction(2));
((NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE)).notify(NOTIFICATION_ID, notificationBuilder.build());
}
private PendingIntent playbackAction(int actionNumber) {
Intent playbackAction = new Intent(this, MediaPlayerService.class);
switch (actionNumber) {
case 0:
// Play
playbackAction.setAction(ACTION_PLAY);
return PendingIntent.getService(this, actionNumber, playbackAction, 0);
case 1:
// Pause
playbackAction.setAction(ACTION_PAUSE);
return PendingIntent.getService(this, actionNumber, playbackAction, 0);
case 2:
// Next track
playbackAction.setAction(ACTION_NEXT);
return PendingIntent.getService(this, actionNumber, playbackAction, 0);
case 3:
// Previous track
playbackAction.setAction(ACTION_PREVIOUS);
return PendingIntent.getService(this, actionNumber, playbackAction, 0);
default:
break;
}
return null;
}
private void removeNotification() {
NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
notificationManager.cancel(NOTIFICATION_ID);
}
private void handleIncomingActions(Intent playbackAction) {
if (playbackAction == null || playbackAction.getAction() == null) return;
String actionString = playbackAction.getAction();
if (actionString.equalsIgnoreCase(ACTION_PLAY)) {
transportControls.play();
} else if (actionString.equalsIgnoreCase(ACTION_PAUSE)) {
transportControls.pause();
} else if (actionString.equalsIgnoreCase(ACTION_NEXT)) {
transportControls.skipToNext();
} else if (actionString.equalsIgnoreCase(ACTION_PREVIOUS)) {
transportControls.skipToPrevious();
} else if (actionString.equalsIgnoreCase(ACTION_STOP)) {
transportControls.stop();
}
}
/**
* Play new Audio
*/
private BroadcastReceiver playNewAudio = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
//Get the new media index form SharedPreferences
audioIndex = new StorageUtil(getApplicationContext()).loadAudioIndex();
if (audioIndex != -1 && audioIndex < audioList.size()) {
//index is in a valid range
activeAudio = audioList.get(audioIndex);
} else {
stopSelf();
}
//A PLAY_NEW_AUDIO action received
//reset mediaPlayer to play the new Audio
stopMedia();
mediaPlayer.reset();
initMediaPlayer();
updateMetaData();
buildNotification(PlaybackStatus.PLAYING);
}
};
private void register_playNewAudio() {
//Register playNewMedia receiver
IntentFilter filter = new IntentFilter(FragmentRight.Broadcast_PLAY_NEW_AUDIO);
registerReceiver(playNewAudio, filter);
}
我的播放列表片段是这样的：
public class FragmentRight extends Fragment {
public static final String Broadcast_PLAY_NEW_AUDIO = "com.example.anuj.musicmetest.PlayNewAudio";
private OnFragmentInteractionListener mListener;
ArrayList<Audio> localList;
TextView nameView;
private MediaPlayerService mediaPlayer;
boolean serviceBound = false;
public FragmentRight() {
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// Inflate the layout for this fragment
View rootView = inflater.inflate(R.layout.fragment_right, container, false);
nameView = (TextView) rootView.findViewById(R.id.name1);
loadAudio();
RecyclerView recyclerView1 = (RecyclerView) rootView.findViewById(R.id.recycler_view1);
LocalListAdapter localListAdapteradapter = new LocalListAdapter(getActivity().getApplication(), localList);
recyclerView1.setAdapter(localListAdapteradapter);
recyclerView1.setLayoutManager(new LinearLayoutManager(getActivity().getApplication()));
recyclerView1.addOnItemTouchListener(new CustomTouchListener(getActivity(), new onItemClickListener() {
@Override
public void onClick(View view, int index) {
playAudio(index);
Intent intent = new Intent(getActivity(), MusicPlayer.class);
startActivity(intent);
}
}));
return rootView;
}
private ServiceConnection serviceConnection = new ServiceConnection() {
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
// We've bound to LocalService, cast the IBinder and get LocalService instance
MediaPlayerService.LocalBinder binder = (MediaPlayerService.LocalBinder) service;
mediaPlayer = binder.getService();
serviceBound = true;
}
@Override
public void onServiceDisconnected(ComponentName name) {
serviceBound = false;
}
};
private void playAudio(int audioIndex) {
//Check is service is active
if (!serviceBound) {
//Store Serializable audioList to SharedPreferences
StorageUtil storage = new StorageUtil(getActivity().getApplicationContext());
storage.storeAudio(localList);
storage.storeAudioIndex(audioIndex);
Intent playerIntent = new Intent(getActivity(), MediaPlayerService.class);
getActivity().startService(playerIntent);
getActivity().bindService(playerIntent, serviceConnection, Context.BIND_AUTO_CREATE);
} else {
//Store the new audioIndex to SharedPreferences
StorageUtil storage = new StorageUtil(getActivity().getApplicationContext());
storage.storeAudioIndex(audioIndex);
Intent broadcastIntent = new Intent(Broadcast_PLAY_NEW_AUDIO);
getActivity().sendBroadcast(broadcastIntent);
}
}
private void loadAudio() {
ContentResolver contentResolver = getActivity().getContentResolver();
Uri uri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
String selection = MediaStore.Audio.Media.IS_MUSIC + "!= 0";
String sortOrder = MediaStore.Audio.Media.TITLE + " ASC";
Cursor cursor = contentResolver.query(uri, null, selection, null, sortOrder);
if (cursor != null && cursor.getCount() > 0) {
localList = new ArrayList<>();
while (cursor.moveToNext()) {
String localData = cursor.getString(cursor.getColumnIndex(MediaStore.Audio.Media.DATA));
String localTitle = cursor.getString(cursor.getColumnIndex(MediaStore.Audio.Media.TITLE));
String localAlbum = cursor.getString(cursor.getColumnIndex(MediaStore.Audio.Media.ALBUM));
String localArtist = cursor.getString(cursor.getColumnIndex(MediaStore.Audio.Media.ARTIST));
// Save to audioList
localList.add(new Audio(localData, localTitle, localAlbum, localArtist));
}
}
cursor.close();
}
// TODO: Rename method, update argument and hook method into UI event
public void onButtonPressed(Uri uri) {
if (mListener != null) {
mListener.onFragmentInteraction(uri);
}
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentInteractionListener) {
mListener = (OnFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
@Override
public void onDetach() {
super.onDetach();
mListener = null;
}
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
void onFragmentInteraction(Uri uri);
}
@Override
public void onDestroy() {
super.onDestroy();
if (serviceBound) {
getContext().unbindService(serviceConnection);
//service is active
mediaPlayer.stopSelf();
}
}