Flutter，如何为底部导航栏使用 switch case？

Question

Im a beginner in flutter, and I will like to use switch case to route to another pages, I did try to do it but it doesn't work, can anyone tell me what did I done wrong???

Hope someone can solve my problem Hope someone can solve my problem Hope someone can solve my problem Hope someone can solve my problem Hope someone can solve my problem Hope someone can solve my problem

class BottomNavigationEzyMember extends StatefulWidget {
  const BottomNavigationEzyMember({Key key}) : super(key: key);

  @override
  _BottomNavigationEzyMemberState createState() =>
      _BottomNavigationEzyMemberState();
}

class _BottomNavigationEzyMemberState extends State<BottomNavigationEzyMember> {
  int _selectedIndex = 0;

  var bottomTextStyle =
      GoogleFonts.inter(fontSize: 12, fontWeight: FontWeight.w500);

  void _onItemTapped(int index) {
    setState(() {
      _selectedIndex = index;
    });
  }

@override
  Widget build(BuildContext context) {
        (index) {
      switch (_selectedIndex) {
        case 0:
          Navigator.of(context).pushNamed('/homepage');
          break;
        case 1:
          Navigator.of(context).pushNamed('/cardpage');
          break;
      }
    };
    return Container(
      height: 64,
      decoration: BoxDecoration(
        color: mFillColor,
        boxShadow: [
          BoxShadow(
              color: Colors.grey.withOpacity(0.3),
              spreadRadius: 2,
              blurRadius: 15,
              offset: const Offset(0, 5))
        ],
        borderRadius: const BorderRadius.only(
          topLeft: Radius.circular(24),
          topRight: Radius.circular(24),
        ),
      ),
      child: BottomNavigationBar(
        items: <BottomNavigationBarItem>[
          BottomNavigationBarItem(
            icon: _selectedIndex == 0
                ? SvgPicture.asset('assets/icons/home_colored.svg')
                : SvgPicture.asset('assets/icons/home.svg'),
            title: Text('Home', style: bottomTextStyle),
          ),
          BottomNavigationBarItem(
            icon: _selectedIndex == 1
                ? SvgPicture.asset('assets/icons/order_colored.svg')
                : SvgPicture.asset('assets/icons/order.svg'),
            title: Text(
              'My Card',
              style: bottomTextStyle,
            ),
          ),
          BottomNavigationBarItem(
            icon: _selectedIndex == 2
                ? SvgPicture.asset('assets/icons/watch_colored.svg')
                : SvgPicture.asset('assets/icons/watch.svg'),
            title: Text(
              'Watch List',
              style: bottomTextStyle,
            ),
          ),
          BottomNavigationBarItem(
            icon: _selectedIndex == 3
                ? SvgPicture.asset('assets/icons/account_colored.svg')
                : SvgPicture.asset('assets/icons/account.svg'),
            title: Text(
              'Account',
              style: bottomTextStyle,
            ),
          ),
        ],
        currentIndex: _selectedIndex,
        selectedItemColor: mBlueColor,
        unselectedItemColor: mSubtitleColor,
        onTap: _onItemTapped,
        backgroundColor: Colors.transparent,
        type: BottomNavigationBarType.fixed,
        selectedFontSize: 12,
        showUnselectedLabels: true,
        elevation: 0,
      ),
    );
  }
}

Answer 1

Remove switch statement from under buildContext ; you will use switch statement under _onItemTapped .

  void _onItemTapped(int index) {
    setState(() {
      print("working");      
      _selectedIndex = index;
      switch (_selectedIndex) {
        case 0:
          Navigator.of(context).pushNamed('/homepage');
          break;
        case 1:
          Navigator.of(context).pushNamed('/cardpage');
          break;
      }

    });
  }