MaterialApp 路由和 BottomNavigationBar答案

【问题标题】：MaterialApp routes and BottomNavigationBarMaterialApp 路由和 BottomNavigationBar
【发布时间】：2021-09-12 13:40:48
【问题描述】：

通过关注此线程，我无法将路线和 BottomNavigationBar (How to use a named routes in a BottomNavigationBar in flutter?) 结合起来。

关于如何使这项工作的任何建议？我正在尝试为一些定义的路线添加一个 BottomNavigationBar。对于其余路线，不应出现 BottomNavigationBar。

void main() {
  runApp(Og1AlarmApp());
}

class Og1AlarmApp extends StatelessWidget {
  final Map<String, WidgetBuilder> _routes = {
    AppRoute.of(AppScreen.alarmList): (c) => AlarmListScreen(),
    AppRoute.of(AppScreen.alarmDetails): (c) => AlarmDetailsScreen(),
    AppRoute.of(AppScreen.alarm): (c) => AlarmScreen(),
    AppRoute.of(AppScreen.dashboard): (c) => DashboardScreen(),
  };

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
        title: 'Og1 Alarm',
        theme: ThemeData(
          primarySwatch: Colors.blue,
        ),
        routes: _routes,
        initialRoute: AppRoute.of(AppScreen.alarmList),
        home: Scaffold(
          body: Center(
            child: _routes[AppRoute.of(AppScreen.alarmList)],
          ),
          bottomNavigationBar: BottomNavigationBar(
            items: <BottomNavigationBarItem>[
              BottomNavigationBarItem(icon: Icon(Icons.alarm_rounded)),
              BottomNavigationBarItem(icon: Icon(Icons.apps_rounded)),
              BottomNavigationBarItem(icon: Icon(Icons.analytics_rounded)),
            ],
            currentIndex: 0,
            selectedItemColor: Palette.gainsboro,
            unselectedItemColor: Palette.lightGray,
            onTap: (index) {
              switch (index) {
                case 0:
                  Navigator.pushNamed(
                      context, AppRoute.of(AppScreen.alarmList));
                  break;
                case 1:
                  Navigator.pushNamed(
                      context, AppRoute.of(AppScreen.dashboard));
                  break;
                case 2:
                  Navigator.pushNamed(
                      context, AppRoute.of(AppScreen.sleepMonitor));
                  break;
              }
            },
          ),
        ));
  }
}

首先在上面的线程中，路由是从 MaterialApp 以某种方式访问的，这在我的情况下会引发错误。其次访问 _routes 变量为 _routes[AppRoute.of(AppScreen.alarmList)] or_routes['/alarmList'] throws (The argument type 'Widget Function(BuildContext)?' can't be assigned to the parameter type 'Widget?' )

感谢您的评价

【问题讨论】：

标签： flutter flutter-routes

【解决方案1】：

我能够按照此处的说明找到解决方案： https://www.vojtech.net/posts/flutter-bottom-navigation/

【讨论】：