CODEWITHSUNDEEP
androidperformanceandroid-intentandroid-fragmentsandroid-activity
Arun kumar
Arun kumar

Reputation: 1894

Android , communicating with background service

I have background service which started on device boot . I want to get some data from that service in my activity .

I want the data, only when my activity start. so the basic requirement is that when my activity start it make a connection with the background service and get the data from this service and when activity stop then disconnect from the service.

Upvotes: 0

Views: 755

Answers (1)

Bharath Mg
Bharath Mg

Reputation: 1127

You need to use bindService() to bind with running service and communicate with it.

Reference : http://developer.android.com/guide/components/bound-services.html

For example (from Android Docs),

public class BindingActivity extends Activity {
YourService mService;
boolean mBound = false;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
}

@Override
protected void onStart() {
    super.onStart();
    // Bind to Your Service
    Intent intent = new Intent(this, YourService.class);
    bindService(intent, mConnection, Context.BIND_AUTO_CREATE);
}

@Override
protected void onStop() {
    super.onStop();
    // Unbind from the service
    if (mBound) {
        unbindService(mConnection);
        mBound = false;
    }
}

/** Called when a button is clicked (the button in the layout file attaches to
  * this method with the android:onClick attribute) */
public void onButtonClick(View v) {
    if (mBound) {
        // Call a method from your Service.
        // However, if this call were something that might hang, then this request should
        // occur in a separate thread to avoid slowing down the activity performance.
        int num = mService.getRandomNumber();
        Toast.makeText(this, "number: " + num, Toast.LENGTH_SHORT).show();
    }
}

/** Defines callbacks for service binding, passed to bindService() */
private ServiceConnection mConnection = new ServiceConnection() {

    @Override
    public void onServiceConnected(ComponentName className,
            IBinder service) {
        // We've bound to the running Service, cast the IBinder and get instance
        LocalBinder binder = (LocalBinder) service;
        mService = binder.getService();
        mBound = true;
    }

    @Override
    public void onServiceDisconnected(ComponentName arg0) {
        mBound = false;
    }
 };
}

In your service,

 public class LocalService extends Service {
    // Binder given to clients
   private final IBinder mBinder = new LocalBinder();
   // Random number generator
   private final Random mGenerator = new Random();

/**
 * Class used for the client Binder.  Because we know this service always
 * runs in the same process as its clients, we don't need to deal with IPC.
 */
public class LocalBinder extends Binder {
    LocalService getService() {
        // Return this instance of LocalService so clients can call public methods
        return LocalService.this;
    }
}

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

/** method for clients */
public int getRandomNumber() {
  return mGenerator.nextInt(100);
  }
}

Basically, you should use bindService() in your activity onStart() and unbindService() in onStop()

Upvotes: 2

Related Questions