LocalBroadcastManager is now deprecated, how to send data from service to activity?

Question

I have a service that needs to notify the main activity. I use LocalBroadcastManager, and it works fine, but LocalBroadcastManager has been deprecated.

This is my actual code in the service:

public void onTokenRefresh() {
      
    /* build the intent */
    Intent intent = new Intent(ACTION_TOKENREFRESHED);
    intent.putExtra("token", "xxx");
    
    /* send the data to registered receivers */
    try{
      LocalBroadcastManager.getInstance(this).sendBroadcast(intent);
    } catch (Throwable e){
      //no exception handling
    }  
  
  }

In the main activity, I get informed of the notification like this :

context.registerReceiver(broadcastReceiver, intentFilter);

What can I use now to remove the deprecated warning? All examples I found regarding sending data from service to activity use LocalBroadcastManager. Can someone give me a workable model for migrating my existing code?

NOTE

In my example, The onTokenRefresh is called from inside a background thread. That is very important because it means I can simultaneously receive several onTokenRefresh, and I must forward all these tokens to the activity. Most of the offered solutions use live data but make a declaration like :

public static final MutableLiveData<String> tokenLiveData = new MutableLiveData<>();

Background Thread1:
tokenLiveData.postValue(Token1);

Background Thread2 (at same time):
tokenLiveData.postValue(Token2);

Will forward ALL tokens received simultaneously to the main activity that observes the tokenLiveData? Will the main activity always receive for sure token1 and token2?

Answer 1

Make a service class and define a LiveData to replace the LocalBroadcastManager responsibility like so:

//This service sends an example token ten times to its observers
public class MyService extends Service {
    //Define a LiveData to observe in activity
    public static final MutableLiveData<String> tokenLiveData = new MutableLiveData<>();

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

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        //You need a separate thread if you don not use IntentService

        Thread thread1 = new Thread() {
            public void run() {
                for (int i = 0; i < 10; i++) {
                    //send random strings az an example token ten times.
                    //You can remove this loop and replace it with your logic
                    String token1 = UUID.randomUUID().toString();
                    new Handler(Looper.getMainLooper()).post(() -> sendTokenToObserver("Thread1: " + token1));

                }
            }
        };
        thread1.start();

        Thread thread2 = new Thread() {
            public void run() {
                for (int i = 0; i < 10; i++) {
                    String token2 = UUID.randomUUID().toString();
                    new Handler(Looper.getMainLooper()).post(() -> sendTokenToObserver("Thread2: " + token2));
                }
            }
        };
        thread2.start();
        return START_STICKY;
    }

    //Post token to observers
    public void sendTokenToObserver(String token) {
        tokenLiveData.setValue(token);

    }
}

Then start the service in the activity and observe the LiveData like below:

public class MainActivity extends AppCompatActivity {

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

        //You can observe the emitted token here and do what you want(Show in view or notification). 
        //I've just logged it to the console.
        startService(new Intent(this,MyService.class));
        MyService.tokenLiveData.observe(this, token -> Log.d("token", token));
    }
}

You can also start the service from another activity and observe it in the MainActivity;