Musikdienst immer null zurück

Question

Ich habe eine Liste von Musiken gemacht und und ein Service-Musik im Hintergrund zu spielen, aber wenn ich auf Musik klicken Sie aus der Liste es immer null zurück

Ich habe noch nie mit Musikdienst arbeiten, so dass ich vielleicht falsch machen hier bin ich falsche Position in Adopter oder etwas anderes passieren?

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; 
    }} 

Aktivitätsklasse

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); 


    } 

Adapterklasse

@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(); 
} 

Fehlerprotokoll

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

Bestätigen Sie, dass, wenn Ihre onServiceConnected Methode aufgerufen und Sie Song-Liste in Ihrem Service-Set, zu diesem Zeitpunkt Ihrer songList prapared ist oder nicht?

Ich meine Ihre Song-Liste kann null sein, wenn Sie unter Zeile aufrufen.

//pass list 
    musicSrv.setList(songList); 

Bei wann Dienst verbunden ist, bevor Sie initLayout Verfahren abgeschlossen.

aktualisieren

Nach unten Zeile Fehlerprotokolle benötigen Sie READ_EXTERNAL_STORAGE Erlaubnis in Ihrer Manifest-Datei hinzuzufügen.

java.lang.SecurityException: Permission Denial: Lesen com.android.providers.media.MediaProvider uri Inhalt: // media/extern/Audio/media/1 von pid = 2608, uid = 1000 erfordert android.permission.READ_EXTERNAL_STORAGE oder grantUriPermission()

Set Datenquelldatei mit 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; 
} 

Zur Kasse gehen this answer für weitere Informationen. Es könnte dir hilfreich sein.

Answer 2

, die nicht Musikdienst Problem ist, dass die Erlaubnis Problem ist

Zuerst müssen Sie Service-Namen geben manifestieren wie

Danach auf Android, wenn Sie 6 läuft.0 oder mehr dann müssen Sie um Erlaubnis fragen, dass Benutzer einen gelesenen externen Speicher schreiben, wenn Anwendung in Lutscher oder in Kitkat oder in anderem, die Erlaubnis zur Installationszeit geben, aber in Marshmallow oder in mehr geben Sie manuell, um Benutzer

zu fragen

check this out Storage permission error in Marshmallow