flutter_integrated_whb/lib/pages/main_tab.dart

// main_page.dart
import 'package:flutter/material.dart';
import 'package:qhd_prevention/pages/badge_manager.dart';
import 'package:qhd_prevention/pages/home/scan_page.dart';
import 'package:qhd_prevention/pages/my_appbar.dart';
import '../customWidget/nfc_test_page.dart';
import 'home/home_page.dart';
import 'app/application_page.dart';
import 'mine/mine_page.dart';
import 'notif/notif_page.dart';

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

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

class _MainPageState extends State<MainPage> {
  int _currentIndex = 0;

  final List<Widget> _pages = const [
    HomePage(),
    ApplicationPage(),
    NotifPage(),
    MinePage(),
  ];
  final List<String> _titles = ['首页', '应用中心', '通知公告', '我的'];

  @override
  void initState() {
    super.initState();
    // 监听 BadgeManager，当角标变化时 setState 刷新 UI
    BadgeManager().addListener(_onBadgeChanged);
  }

  @override
  void dispose() {
    BadgeManager().removeListener(_onBadgeChanged);
    super.dispose();
  }

  void _onBadgeChanged() {
    setState(() {
      // 只是为了重建，让 build 里拿到最新的 appCount / notifCount
    });
  }

  Widget _buildIconWithBadge({
    required Widget icon,
    required int badgeCount,
  }) {
    if (badgeCount <= 0) return icon;
    return Stack(
      clipBehavior: Clip.none,
      children: [
        icon,
        Positioned(
          right: -12,
          top: -4,
          child: Container(
            padding: const EdgeInsets.symmetric(horizontal: 5, vertical: 1),
            decoration: BoxDecoration(
              color: Colors.red,
              borderRadius: BorderRadius.circular(8),
            ),
            constraints: const BoxConstraints(minWidth: 16, minHeight: 16),
            child: Center(
              child: Text(
                badgeCount > 99 ? '99+' : '$badgeCount',
                style: const TextStyle(
                  color: Colors.white,
                  fontSize: 11,
                  height: 1,
                ),
                textAlign: TextAlign.center,
              ),
            ),
          ),
        ),
      ],
    );
  }

  @override
  Widget build(BuildContext context) {
    final bm = BadgeManager();
    return Scaffold(
      appBar: _currentIndex == 1
          ? null
          : MyAppbar(
        title:
        _currentIndex == 0 ? "智守安全首页" : _titles[_currentIndex],
        backgroundColor: Colors.blue,
        isBack: false,
        actions: [
          if (_currentIndex == 0) ...[
            IconButton(
              onPressed: () => Navigator.push(
                context,
                MaterialPageRoute(
                    builder: (_) => NfcTestPage()),
              ),
              icon: Image.asset("assets/images/ai_img.png",
                  width: 20, height: 20),
            ),
            IconButton(
              onPressed: () => Navigator.push(
                context,
                MaterialPageRoute(builder: (_) => ScanPage()),
              ),
              icon: Image.asset("assets/images/scan.png",
                  width: 20, height: 20),
            ),
          ]
        ],
      ),
      body: _pages[_currentIndex],
      bottomNavigationBar: BottomNavigationBar(
        currentIndex: _currentIndex,
        type: BottomNavigationBarType.fixed,
        selectedItemColor: Colors.blue,
        unselectedItemColor: Colors.grey,
        onTap: (i) {
          setState(() => _currentIndex = i);
          // 切到“应用”或“通知”标签时，按需拉最新角标
          if (i == 1) BadgeManager().updateAppCount();
          if (i == 2) BadgeManager().updateNotifCount();
        },
        items: [
          BottomNavigationBarItem(
            icon: Image.asset('assets/tabbar/basics.png', width: 24, height: 24),
            activeIcon:
            Image.asset('assets/tabbar/basics_cur.png', width: 24, height: 24),
            label: '首页',
          ),
          BottomNavigationBarItem(
            icon: _buildIconWithBadge(
              icon: Image.asset('assets/tabbar/application.png',
                  width: 24, height: 24),
              badgeCount: bm.appCount,
            ),
            activeIcon: _buildIconWithBadge(
              icon: Image.asset('assets/tabbar/application_cur.png',
                  width: 24, height: 24),
              badgeCount: bm.appCount,
            ),
            label: '应用',
          ),
          BottomNavigationBarItem(
            icon: _buildIconWithBadge(
              icon: Image.asset('assets/tabbar/works.png',
                  width: 24, height: 24),
              badgeCount: bm.notifCount,
            ),
            activeIcon: _buildIconWithBadge(
              icon: Image.asset('assets/tabbar/works_cur.png',
                  width: 24, height: 24),
              badgeCount: bm.notifCount,
            ),
            label: '通知',
          ),
          BottomNavigationBarItem(
            icon: Image.asset('assets/tabbar/my.png', width: 24, height: 24),
            activeIcon:
            Image.asset('assets/tabbar/my_cur.png', width: 24, height: 24),
            label: '我的',
          ),
        ],
      ),
    );
  }
}