service de musique retourne toujours null

Question

J'ai fait une liste des musiques et et un service à jouer de la musique en arrière-plan, mais quand je clique sur la musique de la liste, il retourne toujours null

J'ai jamais travailler avec le service de la musique pour que je peut-être faire mal ici suis-je en train de passer mauvaise position dans l'adoptant ou autre chose?

Service

public class MusicService extends Service implements 
     MediaPlayer.OnPreparedListener, MediaPlayer.OnErrorListener, 
     MediaPlayer.OnCompletionListener { 

    //media player 
    private MediaPlayer player; 
    //song list 
    private ArrayList<SongModel> songs; 
    //current position 
    private int songPosn; 
    //binder 
    private final IBinder musicBind = new MusicBinder(); 
    //title of current song 
    private String songTitle = ""; 
    //notification id 
    private static final int NOTIFY_ID = 1; 
    //shuffle flag and random 
    private boolean shuffle = false; 
    private Random rand; 

    public void onCreate() { 
     //create the service 
     super.onCreate(); 
     //initialize position 
     songPosn = 0; 
     //random 
     rand = new Random(); 
     //create player 
     player = new MediaPlayer(); 
     //initialize 
     initMusicPlayer(); 
    } 

    public void initMusicPlayer() { 
     //set player properties 
     player.setWakeMode(getApplicationContext(), 
       PowerManager.PARTIAL_WAKE_LOCK); 
     player.setAudioStreamType(AudioManager.STREAM_MUSIC); 
     //set listeners 
     player.setOnPreparedListener(this); 
     player.setOnCompletionListener(this); 
     player.setOnErrorListener(this); 
    } 

    //pass song list 
    public void setList(ArrayList<SongModel> theSongs) { 
     songs = theSongs; 
    } 

    //binder 
    public class MusicBinder extends Binder { 
     public MusicService getService() { 
      return MusicService.this; 
     } 
    } 

    //activity will bind to service 
    @Override 
    public IBinder onBind(Intent intent) { 
     return musicBind; 
    } 

    //release resources when unbind 
    @Override 
    public boolean onUnbind(Intent intent) { 
     player.stop(); 
     player.release(); 
     return false; 
    } 

    //play a song 
    public void playSong() { 
     //play 
     player.reset(); 
     //get song 
     SongModel playSong = songs.get(songPosn); 
     //get title 
     songTitle = playSong.getSongTitle(); 
     //get id 
     long currSong = playSong.getmSongID(); 
     //set uri 
     Uri trackUri = ContentUris.withAppendedId(
       android.provider.MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, 
       currSong); 
     //set the data source 
     try { 
      player.setDataSource(getApplicationContext(), trackUri); 
     } catch (Exception e) { 
      Log.e("MUSIC SERVICE", "Error setting data source", e); 
     } 
     player.prepareAsync(); 
    } 

    //set the song 
    public void setSong(int songIndex) { 
     Log.e("click", " service" + songIndex); 
     for (int i = 0; i < songs.size(); i++) { 
      Log.e("click", songs.get(i).getArtistname() + " " + songs.get(i).getmSongID()); 
     } 
     songPosn = songIndex; 
    } 

    @Override 
    public void onCompletion(MediaPlayer mp) { 
     //check if playback has reached the end of a track 
     if (player.getCurrentPosition() > 0) { 
      mp.reset(); 
      playNext(); 
     } 
    } 

    @Override 
    public boolean onError(MediaPlayer mp, int what, int extra) { 
     Log.v("MUSIC PLAYER", "Playback Error"); 
     mp.reset(); 
     return false; 
    } 

    @Override 
    public void onPrepared(MediaPlayer mp) { 
     //start playback 
     mp.start(); 
     //notification 
     Intent notIntent = new Intent(this, MainActivity.class); 
     notIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); 
     PendingIntent pendInt = PendingIntent.getActivity(this, 0, 
       notIntent, PendingIntent.FLAG_UPDATE_CURRENT); 

     Notification.Builder builder = new Notification.Builder(this); 

     builder.setContentIntent(pendInt) 
       .setSmallIcon(R.mipmap.ic_play_circle_filled_black_24dp) 
       .setTicker(songTitle) 
       .setOngoing(true) 
       .setContentTitle("Playing") 
       .setContentText(songTitle); 
     Notification not = builder.build(); 
     startForeground(NOTIFY_ID, not); 
    } 

    //playback methods 
    public int getPosn() { 
     return player.getCurrentPosition(); 
    } 

    public int getDur() { 
     return player.getDuration(); 
    } 

    public boolean isPng() { 
     return player.isPlaying(); 
    } 

    public void pausePlayer() { 
     player.pause(); 
    } 

    public void seek(int posn) { 
     player.seekTo(posn); 
    } 

    public void go() { 
     player.start(); 
    } 

    //skip to previous track 
    public void playPrev() { 
     songPosn--; 
     if (songPosn < 0) songPosn = songs.size() - 1; 
     playSong(); 
    } 

    //skip to next 
    public void playNext() { 
     if (shuffle) { 
      int newSong = songPosn; 
      while (newSong == songPosn) { 
       newSong = rand.nextInt(songs.size()); 
      } 
      songPosn = newSong; 
     } else { 
      songPosn++; 
      if (songPosn >= songs.size()) songPosn = 0; 
     } 
     playSong(); 
    } 

    @Override 
    public void onDestroy() { 
     stopForeground(true); 
    } 

    //toggle shuffle 
    public void setShuffle() { 
     if (shuffle) shuffle = false; 
     else shuffle = true; 
    }} 

activité classe

public static MusicService musicSrv; 
    private Intent playIntent; 
    private boolean musicBound=false; 

    public static ArrayList<SongModel> songList; 
    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 

     load(); 
    @Override 
    protected void onStart() { 
     super.onStart(); 
     if(playIntent==null){ 
      playIntent = new Intent(this, MusicService.class); 
      bindService(playIntent, musicConnection, Context.BIND_AUTO_CREATE); 
      startService(playIntent); 
     } 
    } 

private ServiceConnection musicConnection = new ServiceConnection() { 

    @Override 
    public void onServiceConnected(ComponentName name, IBinder service) { 
     MusicService.MusicBinder binder = (MusicService.MusicBinder) service; 
     //get service 
     musicSrv = binder.getService(); 
     //pass list 
     musicSrv.setList(songList); 
     musicBound = true; 
    } 

    @Override 
    public void onServiceDisconnected(ComponentName name) { 
     musicBound = false; 
    } 
}; 

    private void initLayout() { 
     final Uri uri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI; 
     final String[] cursor_cols = {MediaStore.Audio.Media._ID, 
       MediaStore.Audio.Media.ARTIST, MediaStore.Audio.Media.ALBUM, 
       MediaStore.Audio.Media.TITLE, MediaStore.Audio.Media.DATA, 
       MediaStore.Audio.Media.ALBUM_ID, 
       MediaStore.Audio.Media.DURATION}; 
     final String where = MediaStore.Audio.Media.IS_MUSIC + "=1"; 
     final Cursor cursor = getContentResolver().query(uri, 
       cursor_cols, where, null, null); 


     while (cursor.moveToNext()) { 
      String artist = cursor.getString(cursor 
        .getColumnIndexOrThrow(MediaStore.Audio.Media.ARTIST)); 
      String album = cursor.getString(cursor 
        .getColumnIndexOrThrow(MediaStore.Audio.Media.ALBUM)); 
      String track = cursor.getString(cursor 
        .getColumnIndexOrThrow(MediaStore.Audio.Media.TITLE)); 
      String data = cursor.getString(cursor 
        .getColumnIndexOrThrow(MediaStore.Audio.Media.DATA)); 
      Long albumId = cursor.getLong(cursor 
        .getColumnIndexOrThrow(MediaStore.Audio.Media.ALBUM_ID)); 

      int duration = cursor.getInt(cursor 
        .getColumnIndexOrThrow(MediaStore.Audio.Media.DURATION)); 

      Uri sArtworkUri = Uri 
        .parse("content://media/external/audio/albumart"); 
      Uri albumArtUri = ContentUris.withAppendedId(sArtworkUri, albumId); 

      Log.e("art", albumArtUri.toString()); 
      /*Bitmap bitmap = null; 
      try { 
       bitmap = MediaStore.Images.Media.getBitmap(
         getActivity().getContentResolver(), albumArtUri); 
       bitmap = Bitmap.createScaledBitmap(bitmap, 30, 30, true); 

      } catch (FileNotFoundException exception) { 
       exception.printStackTrace(); 
       bitmap = BitmapFactory.decodeResource(getActivity().getResources(), 
         R.mipmap.ic_music_note_black_24dp); 
      } catch (IOException e) { 

       e.printStackTrace(); 
      }*/ 

      SongModel audioListModel = new SongModel(); 
      audioListModel.setArtistname(artist); 
      // audioListModel.setBitmap(bitmap); 
      audioListModel.setmSongTitle(album); 
      audioListModel.setmSongTitle(track); 
      audioListModel.setData(data); 
      audioListModel.setmSongID(albumId); 
      audioListModel.setSongLength(String.valueOf(duration)); 
      audioListModel.setUri(String.valueOf(albumArtUri)); 
      Log.e("data", "artist :" + artist + " album " + album + " track " + track + " data " + data + " " + "albumId " + albumId 
        + " " + "duration " + duration + " art: " + albumArtUri); 

      songList.add(audioListModel); 

     } 

    } 


    private class GetAudioListAsynkTask extends AsyncTask<Void, Void, Boolean> { 

     private Context context; 

     public GetAudioListAsynkTask(Context context) { 

      this.context = context; 
     } 

     @Override 
     protected void onPreExecute() { 
      super.onPreExecute(); 

     } 

     @Override 
     protected Boolean doInBackground(Void... params) { 
      try { 
       initLayout(); 

       return true; 
      } catch (Exception e) { 
       return false; 

      } 

     } 

     @Override 
     protected void onPostExecute(Boolean result) { 
      Collections.sort(songList, new Comparator<SongModel>() { 
       public int compare(SongModel a, SongModel b) { 
        return a.getSongTitle().compareTo(b.getSongTitle()); 
       } 
      }); 

     } 
    } 

    public void load() { 
     songList = new ArrayList<>(); 
     new GetAudioListAsynkTask(this).execute((Void) null); 


    } 

classe adaptateur

@Override 
public void onBindViewHolder(final Holder holder, final int position) { 
    final SongModel songModel = list.get(holder.getAdapterPosition()); 
    Glide.with(holder.itemView.getContext()).load(songModel.getUri()).error(R.mipmap.ic_music_note_black_24dp).into(holder.imageView); 
    holder.imageView.setImageURI(Uri.parse(songModel.getUri())); 
    holder.artistname.setText(songModel.getArtistname()); 
    holder.duration.setText(songModel.getSongLength()); 
    holder.songname.setText(songModel.getSongTitle()); 
    holder.itemView.setTag(position); 

    holder.itemView.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View v) { 

      songPicked(position); 
     } 
    }); 


} 
private void songPicked(int position) { 
    musicSrv.setSong(position); 
    musicSrv.playSong(); 
} 

erreur journal

04-21 19:01:37.847 3983-29870/? E/DatabaseUtils: Writing exception to parcel 
               java.lang.SecurityException: Permission Denial: reading com.android.providers.media.MediaProvider uri content://media/external/audio/media/1 from pid=2608, uid=1000 requires android.permission.READ_EXTERNAL_STORAGE, or grantUriPermission() 
                at android.content.ContentProvider.enforceReadPermissionInner(ContentProvider.java:646) 
                at android.content.ContentProvider$Transport.enforceReadPermission(ContentProvider.java:493) 
                at android.content.ContentProvider$Transport.enforceFilePermission(ContentProvider.java:484) 
                at android.content.ContentProvider$Transport.openFile(ContentProvider.java:380) 
                at android.content.ContentProviderNative.onTransact(ContentProviderNative.java:240) 
                at android.os.Binder.execTransact(Binder.java:453) 


               [ 04-21 19:01:37.847 2264:16266 D/   ] 
               openContentUri(content://media/external/audio/media/1) caught exception -1 
04-21 19:01:37.847 2264-16266/? E/MediaPlayerService: Couldn't open fd for content://media/external/audio/media/1 
04-21 19:01:37.847 19273-19273/? E/MediaPlayer: Unable to create media player 
04-21 19:01:37.847 19273-19273/? E/MUSIC SERVICE: Error setting data source 
                java.io.IOException: setDataSource failed.: status=0x80000000 
                 at android.media.MediaPlayer.nativeSetDataSource(Native Method) 
                 at android.media.MediaPlayer.setDataSource(MediaPlayer.java:1231) 
                 at android.media.MediaPlayer.setDataSource(MediaPlayer.java:1215) 
                 at android.media.MediaPlayer.setDataSource(MediaPlayer.java:1169) 
                 at android.media.MediaPlayer.setDataSource(MediaPlayer.java:1105) 
                 at com.nowsip.musicplayer.service.MusicService.playSong(MusicService.java:118) 
                 at com.nowsip.musicplayer.adapter.SongAdapter.songPicked(SongAdapter.java:86) 
                 at com.nowsip.musicplayer.adapter.SongAdapter.access$000(SongAdapter.java:24) 
                 at com.nowsip.musicplayer.adapter.SongAdapter$1.onClick(SongAdapter.java:52) 
                 at android.view.View.performClick(View.java:5721) 
                 at android.view.View$PerformClick.run(View.java:22620) 
                 at android.os.Handler.handleCallback(Handler.java:739) 
                 at android.os.Handler.dispatchMessage(Handler.java:95) 
                 at android.os.Looper.loop(Looper.java:148) 
                 at android.app.ActivityThread.main(ActivityThread.java:7409) 
                 at java.lang.reflect.Method.invoke(Native Method) 
                 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) 
                 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120) 
04-21 19:01:37.847 19273-19273/? E/MediaPlayer: prepareAsync called in state 1 
04-21 19:01:37.847 19273-19273/? E/AndroidRuntime: FATAL EXCEPTION: main 
                Process: com.nowsip.musicplayer, PID: 19273 
                java.lang.IllegalStateException 
                 at android.media.MediaPlayer.prepareAsync(Native Method) 
                 at com.nowsip.musicplayer.service.MusicService.playSong(MusicService.java:122) 
                 at com.nowsip.musicplayer.adapter.SongAdapter.songPicked(SongAdapter.java:86) 
                 at com.nowsip.musicplayer.adapter.SongAdapter.access$000(SongAdapter.java:24) 
                 at com.nowsip.musicplayer.adapter.SongAdapter$1.onClick(SongAdapter.java:52) 
                 at android.view.View.performClick(View.java:5721) 
                 at android.view.View$PerformClick.run(View.java:22620) 
                 at android.os.Handler.handleCallback(Handler.java:739) 
                 at android.os.Handler.dispatchMessage(Handler.java:95) 
                 at android.os.Looper.loop(Looper.java:148) 
                 at android.app.ActivityThread.main(ActivityThread.java:7409) 
                 at java.lang.reflect.Method.invoke(Native Method) 
                 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) 
                 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120) 
04-21 19:01:37.887 19790-19790/? E/Zygote: v2 
04-21 19:01:37.887 2608-19795/? E/android.os.Debug: ro.product_ship = true 
04-21 19:01:37.887 2608-19795/? E/android.os.Debug: ro.debug_level = 0x4f4c 
04-21 19:01:37.887 2608-19795/? E/android.os.Debug: sys.mobilecare.preload = false 
04-21 19:01:37.897 19790-19790/? E/Zygote: accessInfo : 0 
04-21 19:01:37.897 2608-2803/? E/Qmage: isQIO : stream is not a QIO file 
04-21 19:01:38.457 11589-11589/? E/Qmage: isQIO : stream is not a QIO file 
04-21 19:01:38.497 11589-11589/? E/Qmage: isQIO : stream is not a QIO file 
04-21 19:01:38.497 11589-11589/? E/Qmage: isQIO : stream is not a QIO file 

Answer 1

Vérifiez que lorsque votre méthode onServiceConnected appelé et que vous définissez la liste chanson dans votre service, à ce moment-là votre songList est prapared ou non? Je veux dire que votre liste de chansons peut être nulle lorsque vous appelez en-dessous de la ligne.

//pass list 
    musicSrv.setList(songList); 

En cas de lorsque le service est connecté avant votre méthode initLayout terminée.

Mise à jour

Selon dessous de la ligne des journaux d'erreurs vous devez ajouter READ_EXTERNAL_STORAGE autorisation dans votre fichier manifeste.

java.lang.SecurityException: Permission Denial: lire com.android.providers.media.MediaProvider uri contenu: // media/externe/audio/media/1 de pid = 2608, 1000 uid = exige android.permission.READ_EXTERNAL_STORAGE ou grantUriPermission()

Set fichier en utilisant la source de données FileDescriptor:

//play a song 
public void playSong() { 
    //play 
    player.reset(); 
    //get song 
    SongModel playSong = songs.get(songPosn); 
    //get title 
    songTitle = playSong.getSongTitle(); 
    //get id 
    long currSong = playSong.getmSongID(); 
    //set uri 
    Uri trackUri = ContentUris.withAppendedId(
      android.provider.MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, 
      currSong); 
    //set the data source 
    try { 
     String filePath = getPathFromContentUri(context, trackUri); 
     File file = new File(filePath); 
     FileInputStream inputStream = new FileInputStream(file);  
     player.setDataSource(inputStream.getFD()); 
     inputStream.close(); 
    } catch (Exception e) { 
     Log.e("MUSIC SERVICE", "Error setting data source", e); 
    } 
    player.prepareAsync(); 
} 


public static String getPathFromContentUri(Context context, Uri contentUri) { 
    String[] proj = { MediaStore.Audio.Media.DATA }; 
    Cursor cursor = context.getContentResolver().query(contentUri, 
      proj, null, null, null); 
    cursor.moveToFirst(); 

    String path = cursor.getString(cursor 
      .getColumnIndexOrThrow(MediaStore.Audio.Media.DATA)); 

    cursor.close(); 
    return path; 
} 

Commander this answer pour plus d'informations. Cela pourrait vous être utile.

Answer 2

Ce n'est pas problème de service de musique qui est un problème d'autorisation

D'abord, vous devez donner le nom du service android manifeste comme

Après que si vous en cours d'exécution 6.0 ou plus alors vous devez demander la permission à l'utilisateur d'écrire un stockage externe de lecture lors de la première exécution en sucette ou kit kat ou autre qui donne la permission au moment de l'installation mais en guimauve ou plus vous donnez manuellement à demander à l'utilisateur

check this out Storage permission error in Marshmallow