使用弹出范围颤动处理嵌套导航器中的后退按钮

Question

我正在尝试使用 Pop Scope 处理我的嵌套导航器。

因为在嵌套路由中，当我点击设备上的后退按钮时，应用程序将关闭。

onInvoked 方法已被弃用，所以我无法解决这个问题。也无法弄清楚实现。

这是我处理导航器的 main_screen.dart 文件：

import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:calistimapp/widgetlar/bottom_navigation.dart';
import 'package:calistimapp/providers/main_screen_provider.dart';
import 'package:calistimapp/screens/job_search.dart';
import 'package:calistimapp/screens/cuzdan.dart';
import 'package:calistimapp/screens/islerim.dart';
import 'package:calistimapp/screens/profil.dart';
import 'package:calistimapp/screens/kategori_sayfalari/komi_garson_screen.dart';
import 'package:calistimapp/screens/kategori_sayfalari/etkinlik_gorevli_screen.dart';
import 'package:calistimapp/screens/kategori_sayfalari/otel_gorevlisi_screen.dart';
import 'package:calistimapp/screens/kategori_sayfalari/diger_isler_screen.dart';
import 'package:calistimapp/screens/job_details_screen.dart';
import 'package:calistimapp/screens/my_job_details_screen.dart';
import 'package:calistimapp/screens/pending_applications_screen.dart';
import 'package:calistimapp/screens/other_accepted_jobs_screen.dart';
import 'package:calistimapp/screens/update_worker_screen.dart';

class MainScreen extends ConsumerStatefulWidget {
  final String initialRoute;

  const MainScreen({Key? key, required this.initialRoute}) : super(key: key);

  @override
  ConsumerState<MainScreen> createState() => _MainScreenState();
}

class _MainScreenState extends ConsumerState<MainScreen> {
  late final PageController _pageController;

  @override
  void initState() {
    super.initState();
    _pageController = PageController();
    WidgetsBinding.instance.addPostFrameCallback((_) {
      final initialPage = _getInitialPage(widget.initialRoute);
      ref.read(mainScreenProvider.notifier).setPage(initialPage);
      _pageController.jumpToPage(initialPage);
    });
  }

  @override
  void dispose() {
    _pageController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final currentIndex = ref.watch(mainScreenProvider);

    return Scaffold(
      body: PageView(
        controller: _pageController,
        physics: const NeverScrollableScrollPhysics(),
        onPageChanged: (index) {
          ref.read(mainScreenProvider.notifier).setPage(index);
        },
        children: [
          Navigator(
            onGenerateRoute: (settings) => _generateRoute(settings, const JobSearchScreen()),
          ),
          Navigator(
            onGenerateRoute: (settings) => _generateRoute(settings, const CuzdanScreen()),
          ),
          Navigator(
            onGenerateRoute: (settings) => _generateRoute(settings, const IslerimScreen()),
          ),
          Navigator(
            onGenerateRoute: (settings) => _generateRoute(settings, const ProfilScreen()),
          ),
        ],
      ),
      bottomNavigationBar: CustomBottomNavigationBar(
        currentIndex: currentIndex,
        onTap: (index) {
          _pageController.jumpToPage(index);
        },
      ),
    );
  }

  int _getInitialPage(String route) {
    switch (route) {
      case '/job_search':
        return 0;
      case '/cuzdan':
        return 1;
      case '/islerim':
        return 2;
      case '/profil':
        return 3;
      default:
        return 0;
    }
  }

  PageRouteBuilder _generateRoute(RouteSettings settings, Widget defaultPage) {
    Widget page;
    switch (settings.name) {
      case '/komi_garson':
        page = const KomiGarsonScreen();
        break;
      case '/etkinlik_gorevli':
        page = const EtkinlikGorevliScreen();
        break;
      case '/otel_gorevlisi':
        page = const OtelGorevlisiScreen();
        break;
      case '/diger_isler':
        page = const DigerIslerScreen();
        break;
      case '/job_details':
        final jobId = settings.arguments as String;
        page = JobDetailsScreen(jobId: jobId);
      
      case '/my_job_details':
        final jobId = settings.arguments as String;
        page = MyJobDetailsScreen(jobId: jobId);
      
      case '/pending_applications':
        page = const PendingApplicationsScreen();
        break;
      case '/other_accepted_jobs':
        page = const OtherAcceptedJobsScreen();
        break;
      case '/update-worker':
        page = const UpdateWorkerScreen();
        break;
      
    
       
      default:
        page = defaultPage;
    }

    return PageRouteBuilder(
      pageBuilder: (context, animation, secondaryAnimation) => page,
      transitionsBuilder: (context, animation, secondaryAnimation, child) {
        const begin = Offset(1.0, 0.0);
        const end = Offset.zero;
        const curve = Curves.easeInOut;
        var tween = Tween(begin: begin, end: end).chain(CurveTween(curve: curve));
        var offsetAnimation = animation.drive(tween);
        return SlideTransition(
          position: offsetAnimation,
          child: child,
        );
      },
      transitionDuration: const Duration(milliseconds: 300),
    );
  }
}

我尝试使用后退按钮返回到之前的页面。

在嵌套的导航器/路线中，应用程序关闭而不是返回到上一个屏幕。

Answer 1

WillPopScope 小部件可以与上面的方法一起使用，以便在提供嵌套导航器的情况下正确处理 Flutter 应用程序中的后退按钮。它控制当您按下后退按钮时会发生什么。由于现在已弃用 onInvoked 方法，因此 WillPopScope 是实现此目的的正确方法。因此，您需要使用 WillPopScope 包装这些嵌套导航器并手动处理后退导航行为。