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bind to already running Service

Heres my problem:
I am implementing a music player (PlayerActivity.java / xml) which is bound to a service (PlayerService.java) that basically is just an instance of a musicplayer so that it can run in the background. When lefting the app or changing the activity and the restarting the activity i want to bind to the still running service without stopping or restarting it. I have tried using only bindService() but that made me face the problem: somehow without calling startService() before bindService the Service doesn't get initialized or it takes a few milliseconds so that the functions only get null when accessing service functions.
Here is my service class:
public class playerService extends Service {
public boolean running = false;
public MediaPlayer mediaPlayer;
public boolean isPrepared = false;
private String url;
public class serviceBinder extends Binder {
public playerService getService() {
return playerService.this;
}
}
public boolean isRunning(){
return running;
}
private IBinder mBinder = new serviceBinder();
#Nullable
#Override
public IBinder onBind(Intent intent) {
return mBinder;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.w("Service", "started");
mediaPlayer = new MediaPlayer();
running = true;
Log.e("!!!", running + "");
return START_STICKY;
}
public void pause() {
mediaPlayer.pause();
}
public void resume() {
mediaPlayer.start();
}
public void setupPlayer() {
try {
if (mediaPlayer != null) {
mediaPlayer.reset();
}
} catch (Exception e) {
Log.e("MediaPlayer", e.getMessage());
}
try {
mediaPlayer.setDataSource(url);
mediaPlayer.prepareAsync();
} catch (Exception e) {
Log.e("MediaPlayerToo", e.getMessage());
}
}
public void reset(){
mediaPlayer.reset();
}
public void updateUrl(String url){
this.url = url;
}
public void start(){
mediaPlayer.start();
}
public int getCurrentPosition(){
return mediaPlayer.getCurrentPosition();
}
public int getDuration(){
return mediaPlayer.getDuration();
}
#Override
public void onDestroy() {
super.onDestroy();
mediaPlayer.stop();
mediaPlayer.reset();
}
}
I experimented with waiting until the Service has started with a boolean. But when i add any kind of code
after
mService = binder.getService();
startService(intent);
it seems to not get created at all.
Here is also my onServiceConnected class
#Override
public void onServiceConnected(ComponentName name, IBinder service) {
playerService.serviceBinder binder = (playerService.serviceBinder) service;
Intent intent = new Intent(getApplicationContext(), playerService.class);
mService = binder.getService();
startService(intent);
//... <- adding code here will result in the Service not starting?!!
}
I know that my problem is quite confusing, but this was the best i could come up explaining it. I would be really glad if you had any idea because this problem stops me from deployment. Thank you very much!!

Service getting killed even if the app is in Background

I am using a Service for performing some task, which should run only if the app is in background, moreover the service runs for sometime and after sometime, it gets destroyed. Earlier this was working completely fine, but don't know where i am doing wrong.
Here is the code of my Service:
public class MyService extends Service {
Context context;
public static final String TAG = MyService.class.getSimpleName();
public MyService(Context applicationContext) {
super();
context = applicationContext;
Log.i("myservice", "here service created!");
}
public MyService() {
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.d(TAG, "[onCreateService]");
super.onStartCommand(intent, flags, startId);
// Code
registerOverlayReceiver();
context = this;
return START_STICKY;
}
#Override
public void onDestroy() {
super.onDestroy();
unregisterOverlayReceiver();
Log.i("EXIT", "ondestroy!");
}
#Override
public void onTaskRemoved(Intent rootIntent) {
super.onTaskRemoved(rootIntent);
}
#Nullable
#Override
public IBinder onBind(Intent intent) {
return null;
}
private void unregisterOverlayReceiver() {
if (myReceiver != null) {
unregisterReceiver(myReceiver);
}
}
private static final String ACTION_DEBUG = "abc.action.DEBUG";
private void registerOverlayReceiver() {
IntentFilter filter = new IntentFilter();
filter.addAction(Intent.ACTION_SCREEN_ON);
filter.addAction(ACTION_DEBUG);
registerReceiver(myReceiver, filter);
}
private BroadcastReceiver myReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
Log.d(TAG, "[onReceive]" + action);
if (action.equals(Intent.ACTION_SCREEN_ON)) {
showMyActivity();
} else if (action.equals(ACTION_DEBUG)) {
showMyActivity();
}
}
};
private void showMyActivity() {
Intent intent = new Intent();
intent.setClass(this, MyActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_BROUGHT_TO_FRONT);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
}
}
I have debugged but couldn't find out the problem for the same.
Anybody who came across anything like this can help me out.

Android - Service doesn't create

I have some programm, where I want to save the instance of service and use it in another activities. But service doesn't create.
Just see the code, please.
MainActivity.java:
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
MainService.get(this);
}
}
MainService.java:
public class MainService extends Service {
public static Object sWait = new Object();
public static MainService instance;
#Override
public IBinder onBind(Intent intent) {
return null;
}
public static MainService get(Context mContext) {
if (instance == null) {
Intent intent = new Intent(mContext, MainService.class);
mContext.startService(intent);
}
while (true) {
if (instance != null) {
Log.v("myLogs", "all is good!");
break;
}
synchronized (sWait) {
try {
sWait.wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
return instance;
}
#Override
public void onCreate() {
Log.v("myLogs", "created!");
instance = this;
synchronized (sWait) {
sWait.notify();
}
}
}
When I don't use while in MainService.get(), service creates. I added this service to manifest file. I don't know where is there error. I need your help.

That's just not the way you should use Service in Android.
What you probably need is to use bindService() call from your Activity.
See more about bound service here http://developer.android.com/guide/components/bound-services.html
If you need the service to be the same instance each time you bind to it, call startService once when your application start.
Example code:
public class LocalBinder<T> extends Binder {
private WeakReference<T> mService;
public LocalBinder(T service) {
mService = new WeakReference<T>(service);
}
public T getService() {
return mService.get();
}
}
public class MyService extends Service {
private final LocalBinder<MyService> binder;
public MyService() {
binder = new LocalBinder<MyService>(this);
}
#Override
public IBinder onBind(Intent intent) {
return binder;
}
}
public class MyActivity extends Activity implements ServiceConnection {
#Override
protected void onStart() {
super.onStart();
bindService(new Intent(this, MyService.class), this, Context.BIND_AUTO_CREATE);
}
#Override
protected void onStop() {
super.onStop();
unbindService(this);
}
#SuppressWarnings("unchecked")
#Override
public void onServiceConnected(ComponentName name, IBinder service) {
MyService serv = ((LocalBinder<MyService>) service).getService();
// serv is your service instance now
}
#Override
public void onServiceDisconnected(ComponentName name) {
}
}

To start your service use (call this from your activity!):
Intent serviceIntent = new Intent(this, MainService.class);
startService(serviceIntent);
see docs: https://developer.android.com/training/run-background-service/send-request.html

That is definitely not the way you are supposed to use services in android.
I would suggest you revisit the offical android docs.
To get a quick introduction visit this tutorial here.

How to pass a handler from activity to service

How to pass handler from an activity to service? I am trying to update the activity UI on the state of Bluetooth connection by using Handler as shown below from service class.
mHandler.obtainMessage(MenuActivity.MESSAGE_STATE_CHANGE, state, -1).sendToTarget();
In the activity, I implemented this:
public void handleMessage(Message msg) {
switch (msg.what) {
case MESSAGE_STATE_CHANGE:
if (true)
Log.i(TAG, "MESSAGE_STATE_CHANGE: " + msg.arg1);
switch(msg.arg1){
case BluetoothService.STATE_CONNECTED:
showToast("Connected to " + mConnectedDeviceName, Toast.LENGTH_SHORT);
break;
I tried to use a constructor to pass the handler from the activity to service like this:
public BluetoothService(Handler handler, BluetoothAdapter mBluetoothAdapter) {
mAdapter = mBluetoothAdapter;
mState = STATE_NONE;
mHandler = handler;
}
But there was an error which shows Unable to instantiate service and found that the service needs to have a public no-args constructor. But after removing the constructor, the handler did not get passed into the service.
How to solve this problem?

You have to bind to the service from activity and establish a ServiceConnection and then get the instance of service and set your handler.
Here is the activity and service class which i use for one of my media player application.....
public class MainActivity extends Activity
{
private CustomService mService = null;
private boolean mIsBound;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
startService(new Intent(this.getBaseContext(), CustomService.class));
doBindService();
}
private ServiceConnection mConnection = new ServiceConnection() {
#Override
public void onServiceConnected(ComponentName componentName, IBinder iBinder)
{
mService = ((CustomService.LocalBinder)iBinder).getInstance();
mService.setHandler(yourHandler);
}
#Override
public void onServiceDisconnected(ComponentName componentName)
{
mService = null;
}
};
private void doBindService()
{
// Establish a connection with the service. We use an explicit
// class name because we want a specific service implementation that
// we know will be running in our own process (and thus won't be
// supporting component replacement by other applications).
bindService(new Intent(this,
CustomService.class), mConnection, Context.BIND_AUTO_CREATE);
mIsBound = true;
}
private void doUnbindService()
{
if (mIsBound)
{
// Detach our existing connection.
unbindService(mConnection);
mIsBound = false;
}
}
#Override
protected void onDestroy()
{
super.onDestroy();
doUnbindService();
}
}
CustomService Code ....
public class CustomService extends Service
{
private final IBinder mIBinder = new LocalBinder();
private Handler mHandler = null;
#Override
public void onCreate()
{
super.onCreate();
}
#Override
public int onStartCommand(Intent intent, int flag, int startId)
{
return START_STICKY;
}
#Override
public void onDestroy()
{
if(mHandler != null)
{
mHandler = null;
}
}
#Override
public IBinder onBind(Intent intent)
{
return mIBinder;
}
public class LocalBinder extends Binder
{
public CustomService getInstance()
{
return CustomService.this;
}
}
public void setHandler(Handler handler)
{
mHandler = handler;
}
}

Android Background Service didn't stop/terminate

I am using a Service to play background Music. The problem is that the music continues playing when i have finished the activity.
Here is code From Main Activity which starts the service
Intent svc=new Intent(HomeActivity.this, BackgroundSoundService.class);
startService(svc);
BackgroundSoundService.java
public class BackgroundSoundService extends Service {
private static final String TAG = null;
public static MediaPlayer player;
public IBinder onBind(Intent arg0) {
return null;
}
#Override
public void onCreate() {
super.onCreate();
Log.d("atMedia", "Backround Music playing");
player = MediaPlayer.create(this, R.raw.background);
player.setLooping(true); // Set looping
player.setVolume(100,100);
}
public int onStartCommand(Intent intent, int flags, int startId) {
player.start();
return 1;
}
public void onStart(Intent intent, int startId) {
// TO DO
}
public IBinder onUnBind(Intent arg0) {
// TO DO Auto-generated method
return null;
}
public void onStop() {
}
public void onPause() {
}
#Override
public void onDestroy() {
super.onDestroy();
player.stop();
player.release();
}
#Override
public void onLowMemory() {
}
}

Try to stop service from your MainActivity:
Intent svc=new Intent(HomeActivity.this, BackgroundSoundService.class);
stopService(svc);

You have to call selfStop() method inside your service.
or use stopService() API