To know if App has gone to background or is in foreground

MyApplication.java

public class MyApplication implements LifecycleObserver {
  
  @Override
  public void onCreate() {
    ProcessLifecycleOwner.get().getLifecycle().addObserver(this);
  }
  
  @OnLifecycleEvent(Lifecycle.Event.ON_START)
  public void onStart() {
    Log.d("App in foreground");
  }

  @OnLifecycleEvent(Lifecycle.Event.ON_STOP)
  public void onStop() {
    Log.d("App in background");
  }
}