如何在flutter中实现这样的底部导航栏

TabBarView小部件可能会有很大帮助

 import 'package:flutter/material.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      title: 'Flutter Demo',
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.brown),
        useMaterial3: true,
      ),
      home: const MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key});

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> with TickerProviderStateMixin {
  late TabController tabController;
  @override
  void initState() {
    super.initState();
    tabController = TabController(
      initialIndex: 0,
      length: 4,
      vsync: this,
    );
  }

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Stack(
        children: [
          TabBarView(
            controller: tabController,
            children: [
              Container(
                  color: Colors.red,
                  child: const Center(child: Text("Page 1"))),
              Container(
                  color: Colors.purple,
                  child: const Center(child: Text("Page 2"))),
              Container(
                  color: Colors.yellow,
                  child: const Center(child: Text("Page 3"))),
              Container(
                  color: Colors.orange,
                  child: const Center(child: Text("Page 4"))),
            ],
          ),
          Positioned(
            bottom: 0,
            right: 0,
            left: 0,
            child: Padding(
              padding: const EdgeInsets.all(28.0),
              child: Container(
                decoration: BoxDecoration(
                    color: Colors.white,
                    borderRadius: BorderRadius.circular(50)),
                child: Padding(
                  padding: const EdgeInsets.symmetric(
                      horizontal: 20.0, vertical: 20),
                  child: TabBar(
                    controller: tabController,
                    indicatorColor: Colors.transparent,
                    unselectedLabelColor: Colors.grey[110],
                    dividerColor: Colors.transparent,
                    tabs: const [
                      Icon(Icons.home),
                      Icon(Icons.heart_broken),
                      Icon(Icons.search),
                      Icon(Icons.account_circle_outlined),
                    ],
                  ),
                ),
              ),
            ),
          ),
        ],
      ),
    );
  }
}