MyLocationListener.java

class MyLocationListener implements LifecycleObserver {
      private boolean enabled = false;
      public MyLocationListener(Context context, Lifecycle lifecycle, Callback callback) {
         ...
      }

      @OnLifecycleEvent(Lifecycle.Event.ON_START) // lifecycle event : onStart()
      void start() {
          if (enabled) {
             // connect
          }
      }

      public void enable() {
          enabled = true;
          if (lifecycle.getCurrentState().isAtLeast(STARTED)) {
              // connect if not connected
          }
      }

      @OnLifecycleEvent(Lifecycle.Event.ON_STOP) // lifecycle event : onStop()
      void stop() {
          // disconnect if connected
      }
  }

class MyActivity extends AppCompatActivity {
      private MyLocationListener myLocationListener;

      public void onCreate(...) {
          myLocationListener = new MyLocationListener(this, getLifecycle(), location -> {
              // update UI
          });
          Util.checkUserStatus(result -> {
              if (result) {
                  myLocationListener.enable();
              }
          });
    }
  }