Android:Music Player,Unable to start service with null point exception?

Question

There were no errors until i added broadcast receiver for showing the progress of the seekbar.The app was working fine before.

Code for the activity.

 package source.justanothermusicplayer;

import java.io.Serializable;
import java.util.ArrayList;
import source.justanothermusicplayer.classes.SongDetails;
import source.justanothermusicplayer.service.Music_service;
import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.pm.ActivityInfo;
import android.media.MediaMetadataRetriever;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.SeekBar;
import android.widget.Toast;
import android.widget.SeekBar.OnSeekBarChangeListener;

public class NowPlaying extends Activity implements OnSeekBarChangeListener,
        Serializable {

    Intent serviceIntent;
    private boolean boolMusicPlaying = false;

    private Button buttonPlayStop;;
    SeekBar seekbar;
    ArrayList<SongDetails> songdetails = new ArrayList<SongDetails>();
    public static final String BROADCAST_SEEKBAR = "source.justanothermusicplayer.sendseekbar";
    Intent intent;

    // Seekbar
    private SeekBar seekBar;
    private int seekMax;
    private static int songEnded = 0;
    boolean mBroadcastIsRegistered;

    int position = 0;

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.now_playing);
        this.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
        Intent i = getIntent();
        position = i.getIntExtra("Data2", 0);
        songdetails = getIntent().getParcelableArrayListExtra("Data1");




        try {intent = new Intent(BROADCAST_SEEKBAR);
        serviceIntent = new Intent(this, Music_service.class);
        initViews();
        setListeners();
        }
        catch(Exception e)
        {}
        playAudio(position);
        buttonPlayStop.setBackgroundResource(R.drawable.pause);
        boolMusicPlaying = true;

    }

    private void setListeners() {
        buttonPlayStop.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                buttonPlayStopClick();
            }
        });
        seekbar.setOnSeekBarChangeListener(this);

    }

    // not working correctly,also i have to add pause and not stop
    private void buttonPlayStopClick() {
        if (!boolMusicPlaying) {
            buttonPlayStop.setBackgroundResource(R.drawable.pause);
            playAudio(position);
            boolMusicPlaying = true;
        } else {
            if (boolMusicPlaying) {
                buttonPlayStop.setBackgroundResource(R.drawable.play);
                stopMusic_service();
                boolMusicPlaying = false;
            }
        }
    }

    private void playAudio(int position2) {

        position2 = position;
        serviceIntent.putParcelableArrayListExtra("sentAudioLink", songdetails);
        serviceIntent.putExtra("postion_service", position);

        try {
            startService(serviceIntent);
        } catch (Exception e) {

            e.printStackTrace();
            Toast.makeText(getApplicationContext(),
                    e.getClass().getName() + " " + e.getMessage(),
                    Toast.LENGTH_LONG).show();
        }
        registerReceiver(broadcastReceiver, new IntentFilter(
                Music_service.BROADCAST_ACTION));
        ;
        mBroadcastIsRegistered = true;

    }

    private void stopMusic_service() {

        if (mBroadcastIsRegistered) {
            try {
                unregisterReceiver(broadcastReceiver);
                mBroadcastIsRegistered = false;
            } catch (Exception e) {
                // Log.e(TAG, "Error in Activity", e);
                // TODO Auto-generated catch block

                e.printStackTrace();
                Toast.makeText(

                getApplicationContext(),

                e.getClass().getName() + " " + e.getMessage(),

                Toast.LENGTH_LONG).show();
            }
        }

        try {
            stopService(serviceIntent);

        } catch (Exception e) {
            e.printStackTrace();
            Toast.makeText(getApplicationContext(),
                    e.getClass().getName() + " " + e.getMessage(),
                    Toast.LENGTH_LONG).show();
        }
        boolMusicPlaying = false;
    }

    private void initViews() {
        buttonPlayStop = (Button) findViewById(R.id.bPlayPause);
        buttonPlayStop.setBackgroundResource(R.drawable.play);
        seekbar = (SeekBar) findViewById(R.id.songProgressBar);
    }

    @Override
    public void onProgressChanged(SeekBar sb, int progress,
            boolean fromUser) {
         if (fromUser) {
             int seekPos = sb.getProgress();
                intent.putExtra("seekpos", seekPos);
                sendBroadcast(intent);
         }
    }

    private void showPD(Intent bufferIntent) {
        String bufferValue = bufferIntent.getStringExtra("buffering");
        int bufferIntValue = Integer.parseInt(bufferValue);

        // When the broadcasted "buffering" value is 1, show "Buffering"
        // progress dialogue.
        // When the broadcasted "buffering" value is 0, dismiss the progress
        // dialogue.

        switch (bufferIntValue) {

        // Listen for "2" to reset the button to a play button
        case 2:
            buttonPlayStop.setBackgroundResource(R.drawable.play);
            break;

        }
    }

    private BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent serviceIntent) {
            updateUI(serviceIntent);
        }
    };

    private void updateUI(Intent serviceIntent) {
        String counter = serviceIntent.getStringExtra("counter");
        String mediamax = serviceIntent.getStringExtra("mediamax");
        String strSongEnded = serviceIntent.getStringExtra("song_ended");
        int seekProgress = Integer.parseInt(counter);
        seekMax = Integer.parseInt(mediamax);
        songEnded = Integer.parseInt(strSongEnded);
        seekBar.setMax(seekMax);
        seekBar.setProgress(seekProgress);
        if (songEnded == 1) {
            buttonPlayStop.setBackgroundResource(R.drawable.play);
        }
    }

    private BroadcastReceiver broadcastBufferReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent bufferIntent) {
            showPD(bufferIntent);
        }
    };

    @Override
    protected void onPause() {
        // Unregister broadcast receiver
        if (mBroadcastIsRegistered) {
            unregisterReceiver(broadcastBufferReceiver);
            mBroadcastIsRegistered = false;
        }
        super.onPause();
    }

    // -- onResume register broadcast receiver. To improve, retrieve saved
    // screen data ---
    @Override
    protected void onResume() {
        // Register broadcast receiver
        if (!mBroadcastIsRegistered) {
            registerReceiver(broadcastBufferReceiver, new IntentFilter(
                    Music_service.BROADCAST_BUFFER));
            mBroadcastIsRegistered = true;
        }
        super.onResume();
    }

    @Override
    public void onStartTrackingTouch(SeekBar seekBar) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onStopTrackingTouch(SeekBar seekBar) {
        // TODO Auto-generated method stub

    }
}

    enter code here

now code for service:

import java.io.IOException;
import java.util.ArrayList;


import source.justanothermusicplayer.NowPlaying;
import source.justanothermusicplayer.R;
import source.justanothermusicplayer.classes.SongDetails;

import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnBufferingUpdateListener;
import android.media.MediaPlayer.OnCompletionListener;
import android.media.MediaPlayer.OnErrorListener;
import android.media.MediaPlayer.OnInfoListener;
import android.media.MediaPlayer.OnPreparedListener;
import android.media.MediaPlayer.OnSeekCompleteListener;
import android.net.Uri;
import android.os.Handler;
import android.os.IBinder;
import android.telephony.PhoneStateListener;
import android.telephony.TelephonyManager;
import android.util.Log;
import android.widget.Toast;

public class Music_service extends Service implements OnCompletionListener,
        OnPreparedListener, OnErrorListener, OnSeekCompleteListener,
        OnInfoListener {
    private static final String TAG = "TELSERVICE";

    ArrayList<SongDetails> songdetails = new ArrayList<SongDetails>();
    MediaPlayer mp = new MediaPlayer();
    Intent bufferIntent;
    int position;
    private static final int NOTIFICATION_ID = 1;
    private boolean isPausedInCall = false;
    private PhoneStateListener phoneStateListener;
    private TelephonyManager telephonyManager;
    private int headsetSwitch = 1;
    public static final String BROADCAST_BUFFER = "source.justanothermusicplayer.broadcastbuffer";

    // ---Variables for seekbar processing---
    String sntSeekPos;
    int intSeekPos;
    int mediaPosition;
    int mediaMax;
    // Intent intent;
    private final Handler handler = new Handler();
    private static int songEnded;
    Intent seekIntent;

    public static final String BROADCAST_ACTION = "source.justanothermusicplayer.seekprogress";

    @Override
    public void onCreate() {
        mp.setOnCompletionListener(this);
        mp.setOnPreparedListener(this);
        mp.setOnErrorListener(this);
        mp.setOnSeekCompleteListener(this);
        mp.setOnInfoListener(this);
        mp.reset();
        bufferIntent = new Intent(BROADCAST_BUFFER);

        // Register headset receiver
        registerReceiver(headsetReceiver, new IntentFilter(
                Intent.ACTION_HEADSET_PLUG));
        seekIntent = new Intent(BROADCAST_ACTION);

    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startid) {
        registerReceiver(broadcastReceiver, new IntentFilter(
                NowPlaying.BROADCAST_SEEKBAR));

        Log.v(TAG, "Starting telephony");

        telephonyManager = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
        Log.v(TAG, "Starting listener");
        phoneStateListener = new PhoneStateListener() {
            @Override
            public void onCallStateChanged(int state, String incomingNumber) {
                // String stateString = "N/A";
                Log.v(TAG, "Starting CallStateChange");
                switch (state) {
                case TelephonyManager.CALL_STATE_OFFHOOK:
                case TelephonyManager.CALL_STATE_RINGING:
                    if (mp != null) {
                        pauseMedia();
                        isPausedInCall = true;
                    }

                    break;
                case TelephonyManager.CALL_STATE_IDLE:
                    // Phone idle. Start playing.
                    if (mp != null) {
                        if (isPausedInCall) {
                            isPausedInCall = false;
                            playMedia();
                        }

                    }
                    break;
                }

            }

        };

        // Register the listener with the telephony manager
        telephonyManager.listen(phoneStateListener,
                PhoneStateListener.LISTEN_CALL_STATE);

        initNotification();
        songdetails = intent.getParcelableArrayListExtra("sentAudioLink");
        position = intent.getIntExtra("postion_service", 0);

        mp.reset();

        // Set up the MediaPlayer data source using the strAudioLink value
        // if (!mp.isPlaying())
        {
            try {
                mp.setDataSource(this,
                        Uri.parse(songdetails.get(position).Path));

            } catch (IllegalArgumentException e) {
                e.printStackTrace();
            } catch (IllegalStateException e) {
                e.printStackTrace();
            } catch (IOException e) {
            } catch (Exception e) {
            }
            try {
                mp.prepare();
            } catch (Exception e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

        }

        setupHandler();

        return START_STICKY;
    }

    private void setupHandler() {
        handler.removeCallbacks(sendUpdatesToUI);
        handler.postDelayed(sendUpdatesToUI, 1000); // 1 second
    }

    private Runnable sendUpdatesToUI = new Runnable() {
        public void run() {
            // // Log.d(TAG, "entered sendUpdatesToUI");

            LogMediaPosition();

            handler.postDelayed(this, 1000); // 2 seconds

        }
    };

    private void LogMediaPosition() {
        // // Log.d(TAG, "entered LogMediaPosition");
        if (mp.isPlaying()) {
            mediaPosition = mp.getCurrentPosition();
            // if (mediaPosition < 1) {
            // Toast.makeText(this, "Buffering...", Toast.LENGTH_SHORT).show();
            // }
            mediaMax = mp.getDuration();
            // seekIntent.putExtra("time", new Date().toLocaleString());
            seekIntent.putExtra("counter", String.valueOf(mediaPosition));
            seekIntent.putExtra("mediamax", String.valueOf(mediaMax));
            seekIntent.putExtra("song_ended", String.valueOf(songEnded));
            sendBroadcast(seekIntent);
        }
    }

    private BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            updateSeekPos(intent);
        }
    };

    // Update seek position from Activity
    public void updateSeekPos(Intent intent) {
        int seekPos = intent.getIntExtra("seekpos", 0);
        if (mp.isPlaying()) {
            handler.removeCallbacks(sendUpdatesToUI);
            mp.seekTo(seekPos);
            setupHandler();
        }

    }



    BroadcastReceiver headsetReceiver = new BroadcastReceiver() {

        private boolean headsetConnected = false;

        @Override
        public void onReceive(Context context, Intent intent) {
            // TODO Auto-generated method stub
            // Log.v(TAG, "ACTION_HEADSET_PLUG Intent received");
            if (intent.hasExtra("state")) {
                if (headsetConnected && intent.getIntExtra("state", 0) == 0) {
                    headsetConnected = false;
                    headsetSwitch = 0;
                    // Log.v(TAG, "State =  Headset disconnected");
                    // headsetDisconnected();
                } else if (!headsetConnected
                        && intent.getIntExtra("state", 0) == 1) {
                    headsetConnected = true;
                    headsetSwitch = 1;
                    // Log.v(TAG, "State =  Headset connected");
                }

            }

            switch (headsetSwitch) {
            case (0):
                headsetDisconnected();
                break;
            case (1):
                break;
            }
        }

        private void headsetDisconnected() {
            stopMedia();
            stopSelf();
        }

    };

    @Override
    public void onDestroy() {
        super.onDestroy();
        if (mp != null) {
            if (mp.isPlaying()) {
                mp.stop();
            }
            mp.release();
        }
        if (phoneStateListener != null) {
            telephonyManager.listen(phoneStateListener,
                    PhoneStateListener.LISTEN_NONE);
        }
        cancelNotification();
        unregisterReceiver(broadcastReceiver);

        unregisterReceiver(headsetReceiver);
        handler.removeCallbacks(sendUpdatesToUI);

    }

    private void initNotification() {
        String ns = Context.NOTIFICATION_SERVICE;
        NotificationManager mNotificationManager = (NotificationManager) getSystemService(ns);
        int icon = R.drawable.ic_launcher;
        CharSequence tickerText = "Tutorial: Music In Service";
        long when = System.currentTimeMillis();
        Notification notification = new Notification(icon, tickerText, when);
        notification.flags = Notification.FLAG_ONGOING_EVENT;
        Context context = getApplicationContext();
        CharSequence contentTitle = "Music In Service App Tutorial";
        CharSequence contentText = "Listen To Music While Performing Other Tasks";
        Intent notificationIntent = new Intent(this, NowPlaying.class);
        PendingIntent contentIntent = PendingIntent.getActivity(context, 0,
                notificationIntent, 0);
        notification.setLatestEventInfo(context, contentTitle, contentText,
                contentIntent);
        mNotificationManager.notify(NOTIFICATION_ID, notification);
    }

    // Cancel Notification
    private void cancelNotification() {
        String ns = Context.NOTIFICATION_SERVICE;
        NotificationManager mNotificationManager = (NotificationManager) getSystemService(ns);
        mNotificationManager.cancel(NOTIFICATION_ID);
    }

    private void resetButtonPlayStopBroadcast() {
        // Log.v(TAG, "BufferCompleteSent");
        bufferIntent.putExtra("buffering", "2");
        sendBroadcast(bufferIntent);
    }

    @Override
    public IBinder onBind(Intent intent) {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public void onCompletion(MediaPlayer mp2) {
        stopMedia();
        position = position + 1;

        try {
            // mp.setDataSource(songdetails.get(position).Path);
            mp.setDataSource(this, Uri.parse(songdetails.get(position).Path));
            mp.prepare();
        } catch (IllegalArgumentException e) {
            e.printStackTrace();
        } catch (SecurityException e) {
            e.printStackTrace();
        } catch (IllegalStateException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

    public void stopMedia() {
        if (mp.isPlaying()) {
            mp.stop();
        }
        mp.reset();
    }

    public void playMedia() {
        // if (!mp.isPlaying())
        {
            mp.start();
        }
    }

    public void pauseMedia() {
        // Log.v(TAG, "Pause Media");
        if (mp.isPlaying()) {
            mp.pause();
        }

    }

    @Override
    public void onPrepared(MediaPlayer arg0) {
        playMedia();

    }

    @Override
    public boolean onError(MediaPlayer mp, int what, int extra) {
        // TODO Auto-generated method stub
        return false;
    }

    @Override
    public void onSeekComplete(MediaPlayer mp2) {
        if (!mp.isPlaying()){
            playMedia();
            Toast.makeText(this,
                    "SeekComplete", Toast.LENGTH_SHORT).show();
        }

    }

    @Override
    public boolean onInfo(MediaPlayer arg0, int arg1, int arg2) {
        // TODO Auto-generated method stub
        return false;
    }

}

now error log

10-09 21:34:27.751: E/AndroidRuntime(553): FATAL EXCEPTION: main
10-09 21:34:27.751: E/AndroidRuntime(553): java.lang.RuntimeException: Error receiving broadcast Intent { act=source.justanothermusicplayer.seekprogress flg=0x10 (has extras) } in source.justanothermusicplayer.NowPlaying$1@40fa2e50
10-09 21:34:27.751: E/AndroidRuntime(553):  at android.app.LoadedApk$ReceiverDispatcher$Args.run(LoadedApk.java:737)
10-09 21:34:27.751: E/AndroidRuntime(553):  at android.os.Handler.handleCallback(Handler.java:605)
10-09 21:34:27.751: E/AndroidRuntime(553):  at android.os.Handler.dispatchMessage(Handler.java:92)
10-09 21:34:27.751: E/AndroidRuntime(553):  at android.os.Looper.loop(Looper.java:137)
10-09 21:34:27.751: E/AndroidRuntime(553):  at android.app.ActivityThread.main(ActivityThread.java:4340)
10-09 21:34:27.751: E/AndroidRuntime(553):  at java.lang.reflect.Method.invokeNative(Native Method)
10-09 21:34:27.751: E/AndroidRuntime(553):  at java.lang.reflect.Method.invoke(Method.java:511)
10-09 21:34:27.751: E/AndroidRuntime(553):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
10-09 21:34:27.751: E/AndroidRuntime(553):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
10-09 21:34:27.751: E/AndroidRuntime(553):  at dalvik.system.NativeStart.main(Native Method)
10-09 21:34:27.751: E/AndroidRuntime(553): Caused by: java.lang.NullPointerException
10-09 21:34:27.751: E/AndroidRuntime(553):  at source.justanothermusicplayer.NowPlaying.updateUI(NowPlaying.java:196)
10-09 21:34:27.751: E/AndroidRuntime(553):  at source.justanothermusicplayer.NowPlaying.access$0(NowPlaying.java:189)
10-09 21:34:27.751: E/AndroidRuntime(553):  at source.justanothermusicplayer.NowPlaying$1.onReceive(NowPlaying.java:185)
10-09 21:34:27.751: E/AndroidRuntime(553):  at android.app.LoadedApk$ReceiverDispatcher$Args.run(LoadedApk.java:728)
10-09 21:34:27.751: E/AndroidRuntime(553):  ... 9 more

Answer 1

try this..

u have specified global seekMax 2 times

return statement of onStartCommand always

return  START_NOT_STICKY;

only

Personally, for a music player, I argue that START_NOT_STICKY is the right answer. If your service is stopped for whatever reason, the user should be in charge of starting it up again.