tabbar.dart

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: kBaseThemeData,
      home: Scaffold(
        body: IndexedStack(
          index: _currentIndex,
          children: <Widget>[
            VocabConfigurationListScreen(),
            GrammarHomeWidget()
          ],
        ),
        bottomNavigationBar: BottomNavigationBar(
          backgroundColor: kBaseThemeData.primaryColor,
          currentIndex: _currentIndex,
          onTap: _onTabTapped,
          items: [
            BottomNavigationBarItem(
              icon: Icon(Icons.description, color: Colors.white,),
              title: Text('Vocabulary', style: TextStyle(color: Colors.white),),
            ),
            BottomNavigationBarItem(
              icon: Icon(Icons.gradient, color: Colors.white,),
              title: Text('Grammar', style: TextStyle(color: Colors.white),),
            ),
          ],
        ),
      )
    );
  }