Android媒体播放器流

我已经用导航抽屉创建了android应用程序来播放在线电台，但当我按下播放按钮启动服务时并没有声音。如何解决这个问题

后台服务

public class BackgroundService extends Service implements OnCompletionListener
{
    MediaPlayer mediaPlayer;
    private String STREAM_URL = "http://178.149.88.126:8010/";

    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    @Override
    public void onCreate()
    {
        SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
                    String radio = sharedPreferences.getString("station", "100");

                    if (radio != null && radio.equals("100"))
                        STREAM_URL = "http://178.149.88.126:8000/";
                    if (radio != null && radio.equals("200"))
                        STREAM_URL = "http://178.149.88.126:8010/";

        mediaPlayer = new MediaPlayer();
        try
        {
            mediaPlayer.setDataSource(STREAM_URL);
        } catch (IOException e)
        {
            e.printStackTrace();
        }

        mediaPlayer.setOnCompletionListener(this);
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId)
    {
        if (!mediaPlayer.isPlaying())
        {
            try
            {
                mediaPlayer.reset();
                mediaPlayer.setDataSource(STREAM_URL);
                mediaPlayer.prepareAsync();

                mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener()
                {
                    @Override
                    public void onPrepared(MediaPlayer mp)
                    {
                        mediaPlayer.start();
                    }
                });
            } catch (IOException e)
            {
                e.printStackTrace();
            }

        }
        return START_STICKY;
    }

    public void onDestroy() {
        if (mediaPlayer.isPlaying()) {
            mediaPlayer.stop();
        }
        mediaPlayer.release();
    }

    public void onCompletion(MediaPlayer _mediaPlayer) {
        stopSelf();
    }


    @Override
    public boolean onUnbind(Intent intent)
    {
        return super.onUnbind(intent);
    }
}

主要片段

public class Main extends Fragment
{
    private ImageButton buttonPlay;
    private MediaPlayer mPlayer;
    Intent playbackServiceIntent;

    private SeekBar volumeSeekbar = null;
    private AudioManager audioManager = null;

    Calendar calendar = Calendar.getInstance();

    View view;

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState)
    {
        view = inflater.inflate(R.layout.fragment_main,container,false);

        buttonPlay = (ImageButton) view.findViewById(R.id.buttonPlay);

        mPlayer = new MediaPlayer();

        initControls();

        buttonPlay.setTag(1);
        buttonPlay.setImageResource(R.drawable.stop);
        buttonPlay.setOnClickListener(new View.OnClickListener()
        {
            @Override
            public void onClick(View view)
            {
                if (Integer.parseInt(buttonPlay.getTag().toString()) == 1)
                {
                    buttonPlay.setImageResource(R.drawable.play);
                    view.setTag(0);

                    getActivity().startService(playbackServiceIntent);

                    Log.e("Play", "onPlay");
                    Toast.makeText(getActivity(), "Play", Toast.LENGTH_SHORT).show();
                } 
                else
                {
                    buttonPlay.setImageResource(R.drawable.stop);
                    view.setTag(1);
                    mPlayer.stop();
                    getActivity().stopService(playbackServiceIntent);
                    Log.e("Stop", "onPlay");
                    Toast.makeText(getActivity(), "Stop", Toast.LENGTH_SHORT).show();
                }

            }
        });
        playbackServiceIntent = new Intent(getActivity(), BackgroundService.class);

        return view;
    }

    @Override
    public void onViewCreated(View view, @Nullable Bundle savedInstanceState)
    {
        super.onViewCreated(view, savedInstanceState);

        getActivity().setTitle("Audiophileradio");
    }

    private void startService()
    {
        getActivity().startService(new Intent(getActivity(),BackgroundService.class));
    }
    private void stopService()
    {
        getActivity().stopService(new Intent(getActivity(),BackgroundService.class));
    }

    private void initControls()
    {
        try
        {
            volumeSeekbar = (SeekBar) view.findViewById(R.id.seekBar);
            audioManager = (AudioManager) getActivity().getSystemService(Context.AUDIO_SERVICE);
            volumeSeekbar.setMax(audioManager
                    .getStreamMaxVolume(AudioManager.STREAM_MUSIC));
            volumeSeekbar.setProgress(audioManager
                    .getStreamVolume(AudioManager.STREAM_MUSIC));
            volumeSeekbar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener()
            {
                @Override
                public void onStopTrackingTouch(SeekBar arg0)
                {
                }

                @Override
                public void onStartTrackingTouch(SeekBar arg0)
                {
                }

                @Override
                public void onProgressChanged(SeekBar arg0, int progress, boolean arg2)
                {
                    audioManager.setStreamVolume(AudioManager.STREAM_MUSIC,
                            progress, 0);
                }
            });
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
    }
}

主要活动

public class MainActivity extends AppCompatActivity
        implements NavigationView.OnNavigationItemSelectedListener
{
    NavigationView navigationView = null;
    Toolbar toolbar = null;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        setTheme(R.style.AppTheme_AppBarOverlay);

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        //initial fragment
        Main main = new Main();
        FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
        fragmentTransaction.replace(R.id.fragment_container, main);
        fragmentTransaction.commit();

        toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.addDrawerListener(toggle);
        toggle.syncState();

        navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);

        if(Build.VERSION.SDK_INT >= 21)
        {
            Window window = this.getWindow();
            window.addFlags(WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS);
            window.clearFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
            window.setStatusBarColor(this.getResources().getColor(R.color.colorPrimary));
        }

        Intent serviceIntent = new Intent(this, NotificationService.class);
        serviceIntent.setAction("FRS");
        startService(serviceIntent);
    }

    boolean doubleBackToExitPressedOnce = false;
    @Override
    public void onBackPressed()
    {
        SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
        boolean confirmation_dialog = sharedPreferences.getBoolean("dialog",false);

        if(confirmation_dialog)
        {
            //Checking for fragment count on backstack
            if (getSupportFragmentManager().getBackStackEntryCount() > 0)
            {
                getSupportFragmentManager().popBackStack();
            } else if (!doubleBackToExitPressedOnce)
            {
                this.doubleBackToExitPressedOnce = true;
                Toast.makeText(this, "Please click BACK again to exit.", Toast.LENGTH_SHORT).show();

                new Handler().postDelayed(new Runnable()
                {

                    @Override
                    public void run()
                    {
                        doubleBackToExitPressedOnce = false;
                    }
                }, 2000);
            } else
            {

                super.onBackPressed();
                return;
            }
        }
        else
        {
            DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
            if (drawer.isDrawerOpen(GravityCompat.START))
            {
                drawer.closeDrawer(GravityCompat.START);
            } else
            {
                super.onBackPressed();
            }
        }
    }

    @SuppressWarnings("StatementWithEmptyBody")
    @Override
    public boolean onNavigationItemSelected(MenuItem item)
    {
        // Handle navigation view item clicks here.
        int id = item.getItemId();

        Intent intent;

        if(id == R.id.home)
        {
            Main main = new Main();
            FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
            fragmentTransaction.replace(R.id.fragment_container, main);
            fragmentTransaction.commit();
        }
        if(id == R.id.settings)
        {
            intent = new Intent(this, SettingsActivity.class);
            startActivity(intent);
            /*Settings settings = new Settings();
            FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
            fragmentTransaction.replace(R.id.fragment_container, settings);
            fragmentTransaction.commit();*/
        }
        if(id == R.id.about)
        {
            intent = new Intent(this, About.class);
            startActivity(intent);
        }
        if(id == R.id.send)
        {
            Feedback feedback = new Feedback();
            FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
            fragmentTransaction.replace(R.id.fragment_container, feedback);
            fragmentTransaction.commit();
        }
        if(id == R.id.share)
        {
            try
            {
                Intent i = new Intent(Intent.ACTION_SEND);
                i.setType("text/plain");
                i.putExtra(Intent.EXTRA_SUBJECT, "Audiophileradio");
                String sAux = "\nLet me recommend you this application\n\n";
                sAux = sAux + "https://play.google.com/store/apps/details?id=Orion.Soft \n\n";
                i.putExtra(Intent.EXTRA_TEXT, sAux);
                startActivity(Intent.createChooser(i, "choose one"));
            } catch (Exception e)
            {
                //e.toString();
            }
        }
        if(id == R.id.exit)
        {
            //stopService(playbackServiceIntent);
            finish();
        }

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        drawer.closeDrawer(GravityCompat.START);

        return true;
    }

    @Override
    public void onDestroy()
    {
        super.onDestroy();

        NotificationManager mNotificationManager =
                (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
        mNotificationManager.cancel(0);
    }
}

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我已经解决了这个问题。我忘记在AndroidManifest.xml中添加