Question

I have an activity in which I start a service, for example I staty MyService as:

Intent intent1 = new Intent(this, MyService.class);
startService(intent1);

Inside my service I create a thread and run it. Here is part of my code:

public class MyService extends Service {
...
@Override
public void onStart(Intent intent, int startid) {
    Thread mythread= new Thread() {
        @Override
        public void run() {
            while(true)
            {
              ...
            }
        }
    };
    mythread.start();
}

}

Now instead of while(true) I want to use while(a), where a is a parameter that is passed from my activity to this service. Please note that my activity is a different class than my service. How can this be done? Please show specific example with some codes.

Answer 1

You can get access to your service by binding to it. Edit your service class so that it returns an IBinder onBind()

public class MyService extends Service {

    private static final String TAG = MyService.class.getSimpleName();
    private final IBinder binder = new ServiceBinder();
    private boolean a;

    @Override
    public IBinder onBind( Intent intent ) {

        return binder;
    }

    @Override
    public int onStartCommand( Intent intent, int flags, int startId ) {

        return super.onStartCommand( intent, flags, startId );
    }

    @Override
    public void onCreate() {

        super.onCreate();
    }

    public class ServiceBinder extends Binder {

        public MyService getService() {

            return MyService.this;
        }
    }

    public void setA(boolean a) {

        this.a = a;
    }
}

Now in your activity you need to handle binding and unbinding to your service. In this example, the service sticks around whether you are bound or not. If this is not the functionality you want, you can just not call startService(...):

public class MyActivity extends Activity {

    //...
    private MyService myService;
    private boolean bound;

    @Override    
    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        Intent intent = new Intent( this, MyService.class );
        startService( intent );
        doBindService();
    }

    private final ServiceConnection serviceConnection = new ServiceConnection() {

        public void onServiceConnected( ComponentName className, IBinder service ) {

            myService = ( (MyService.ServiceBinder) service ).getService();
            bound = true;
        }

        public void onServiceDisconnected( ComponentName className ) {

            myService = null;
            bound = false;
        }
    };

    void doBindService() {

        boolean bound = bindService( new Intent( this, MyService.class ), serviceConnection, Context.BIND_AUTO_CREATE );
        if ( bound ) {

            Log.d( TAG, "Successfully bound to service" );
        }
        else {

            Log.d( TAG, "Failed to bind service" );
        }
    }

    void doUnbindService() {

        unbindService( serviceConnection );
    }
}

Now you have a reference to your bound service in your activity and you can just call myService.setA(true) to set your parameter.