anchor.diff:    _BottomTabBarState(this.observer);
   
     final FirebaseAnalyticsObserver observer;
  +  int selectedIndex = 0;
   
     @override
     void didChangeDependencies() {
  
positive.code:     Profile(),
    ];
  
    int selectedIndex = 0;
  
    final List<String> tabNames = ['home', 'maps', 'notifications', 'profile'];
  
    @override
  
negative.code: 
    void _sendCurrentTabToAnalytics() {
      observer.analytics.setCurrentScreen(
        screenName: '${BottomTabBar.routeName}/${widget.tabNames[selectedIndex]}',
      );
    }
  }
  