Intent Service Class sample

public class MyIntentService extends IntentService {

    public static final String Somevariables = "somevalue";

    public MyIntentService() {

        super(MyIntentService.class.getName()); // you can give any string but it is good practice to giving classname
    }

    @Override
    public void onCreate() {
        super.onCreate();
        //--some code --
    }

    @Override
    protected void onHandleIntent(Intent intent) {
        
        //you can retrive intent extras
        String msg = intent.getStringExtra(EXTRA_KEY);

        //--actual backgroung code gos here  --
    }
}

Add service in manifest also

<service android:name=".MyIntentService"/>

ref: https://developer.android.com/training/run-background-service/create-service.html