从不同的屏幕导航到底部导航栏中的屏幕并重新加载状态

Question

我一直在用 Flutter 创建一个应用程序，我被这个问题困住了。我的底部导航栏中有 5 个项目，其中两个是 HomeSreen 和 AddCashScreen。 HomeScreen 是我的应用程序中的主屏幕，它由一些重要的 API 组成，这些 API 在我们一开始进入此页面时会起作用。

AddCashScreen 上有一个 Button("Proceed to add cash")，如果我们点击它，就会运行一个 API，在服务器端记录成功后，用户应该回到 HomeScreen 页面并且HomeScreen 中的所有 API 都必须再次运行（这很重要）。

这就是问题发生的地方，点击按钮后，用户仍然在 AddCashScreen 上，但在 HomeScreen 中可以看到一个新的导航栏（由相同的项目组成）。我不知道如何解决问题。如果有人可以帮忙，请看一看。 （PS：我是 Flutter 新手）

这是主屏幕：

class HomeScreen extends StatefulWidget {
@override
HomeScreenState createState() =>
  new HomeScreenState(_user, _googleSignIn, landingPage);
}

class HomeScreenState extends State<HomeScreen> {
int landingPage = 0;
int currentIndex;


HomeScreenState();

List<GlobalKey<NavigatorState>> _navigatorKeys = [
GlobalKey<NavigatorState>(),
GlobalKey<NavigatorState>(),
GlobalKey<NavigatorState>(),
GlobalKey<NavigatorState>(),
GlobalKey<NavigatorState>(),
];

getValueForDisplayNAme() {
 if (_user == null) {
  displayName = "";
 }
}

@override
Widget build(BuildContext context) {
void onTabTapped(int index) {
  setState(() {
    currentIndex = index;
  });
}

return WillPopScope(
    onWillPop: () async {
      final isFirstRouteInCurrentTab =
          !await _navigatorKeys[currentIndex].currentState.maybePop();

      // let system handle back button if we're on the first route
      return isFirstRouteInCurrentTab;
    },
    child: MultiProvider(
      providers: [
        ChangeNotifierProvider(create: (context) => AddCashValue()),
      ],
      child: Scaffold(
          body: Stack(
            children: [
              _buildOffstageNavigator(0),
              _buildOffstageNavigator(1),
              _buildOffstageNavigator(2),
              _buildOffstageNavigator(3),
              _buildOffstageNavigator(4),
            ],
          ),
          bottomNavigationBar: _createBottomNavigationBar()),
    ));
// TODO: implement build
}

Route _createRoute(route) {
return PageRouteBuilder(
  pageBuilder: (context, animation, secondaryAnimation) => route(),
  transitionsBuilder: (context, animation, secondaryAnimation, child) {
    return child;
  },
);
}

Widget _createBottomNavigationBar() {
 return Container(
  decoration: BoxDecoration(
    gradient: LinearGradient(
      colors: [blue1, dark1],
      begin: Alignment.topLeft,
      end: Alignment.bottomLeft,
      stops: [0.0, 0.8],
      tileMode: TileMode.clamp,
    ),
  ),
  child: BottomNavigationBar(
    currentIndex: currentIndex,
    onTap: (index) {
      print("index   :   " + index.toString());
      setState(() {
        currentIndex = index;
      });
    },
    showUnselectedLabels: true,
    backgroundColor: Colors.transparent,
    type: BottomNavigationBarType.fixed,
    fixedColor: Colors.white,
    unselectedIconTheme: IconThemeData(color: Colors.blue),
    unselectedItemColor: Colors.blue,
    selectedFontSize: 12.0,
    unselectedFontSize: 12.0,
    elevation: 50.0,
    selectedIconTheme: IconThemeData(color: Colors.white),
    items: [
      BottomNavigationBarItem(
        icon: Padding(
          padding: const EdgeInsets.all(5.0),
          child: new Image.asset('assets/images/all_game.png',
              fit: BoxFit.contain),
        ),
        // ignore: deprecated_member_use
        title: Text("All Games"),
      ),
      BottomNavigationBarItem(
        icon: Padding(
          padding: const EdgeInsets.all(5.0),
          child: new Image.asset('assets/images/deals.png',
              fit: BoxFit.contain),
        ),
        title: Text("Deals"),
      ),
      BottomNavigationBarItem(
        icon: Padding(
          padding: const EdgeInsets.all(5.0),
          child: new Image.asset('assets/images/add_cash.png',
              fit: BoxFit.contain),
        ),
        // ignore: deprecated_member_use
        title: Text("Add Cash"),
      ),
      BottomNavigationBarItem(
        icon: Padding(
          padding: const EdgeInsets.all(5.0),
          child: new Image.asset('assets/images/refer.png',
              fit: BoxFit.contain),
        ),
        // ignore: deprecated_member_use
        title: Text("Refer and Earn"),
      ),
      BottomNavigationBarItem(
        icon: Padding(
          padding: const EdgeInsets.all(5.0),
          child: new Image.asset('assets/images/chat.png',
              fit: BoxFit.contain),
        ),
        // ignore: deprecated_member_use
        title: Text("Support"),
      )
    ],
  ),
);
}

Map<String, WidgetBuilder> _routeBuilders(BuildContext context, int index) {
return {
  '/': (context) {
    return [
      AllGamesScreen(),
      DealsScreen(),
      AddCash(),
      ReferAndEarnScreen(),
      SupportScreen(),
    ].elementAt(index);
  },
};
}

Widget _buildOffstageNavigator(int index) {
 var routeBuilders = _routeBuilders(context, index);

 return Offstage(
  offstage: currentIndex != index,
  child: Navigator(
    key: _navigatorKeys[index],
    onGenerateRoute: (routeSettings) {
      return MaterialPageRoute(
        builder: (context) => routeBuilders[routeSettings.name](context),
      );
    },
  ),
);
}

noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
}

这是我的 AddCashScreen：

class AddCash extends StatefulWidget {
AddCash();

@override
_AddCashState createState() => _AddCashState(_user, _googleSignIn);
}

class _AddCashState extends State<AddCash> {
@override
Widget build(BuildContext context) {
return Scaffold(
  resizeToAvoidBottomInset: false,
  body: Container(
    child: GestureDetector(
      onTap: () {
           //API call
           //After success {
               Navigator.pushAndRemoveUntil(
                context,
                MaterialPageRoute(
                 builder: (BuildContext context) =>
                 HomeScreen(),
                ),
               (route) => true,
               );
          }
      },
      child: Text(
          "Proceed to Add Cash",
          ),
      ),
   ),
 ),
}