connect with backend

lib/screens/main_bottom_nav.dart

@@ -0,0 +1,56 @@
+import 'package:flutter/material.dart';
+import '../widgets/main_app_bar.dart';
+import 'dashboard_screen.dart';
+import 'order_screen.dart';
+import 'invoice_screen.dart';
+import 'chat_screen.dart';
+import 'settings_screen.dart';
+
+class MainBottomNav extends StatefulWidget {
+  const MainBottomNav({super.key});
+
+  @override
+  State<MainBottomNav> createState() => MainBottomNavState();
+}
+
+class MainBottomNavState extends State<MainBottomNav> {
+  int _currentIndex = 0;
+
+  void setIndex(int index) {
+    setState(() {
+      _currentIndex = index;
+    });
+  }
+
+  final List<Widget> _screens = const [
+    DashboardScreen(),
+    OrdersScreen(),
+    InvoiceScreen(),
+    ChatScreen(),
+    SettingsScreen(),
+  ];
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: const MainAppBar(),
+      body: _screens[_currentIndex],
+      bottomNavigationBar: BottomNavigationBar(
+        currentIndex: _currentIndex,
+        selectedItemColor: Colors.red,
+        unselectedItemColor: Colors.black,
+        type: BottomNavigationBarType.fixed,
+        onTap: (index) {
+          setState(() => _currentIndex = index);
+        },
+        items: const [
+          BottomNavigationBarItem(icon: Icon(Icons.dashboard_outlined), label: "Dashboard"),
+          BottomNavigationBarItem(icon: Icon(Icons.shopping_bag_outlined), label: "Orders"),
+          BottomNavigationBarItem(icon: Icon(Icons.receipt_long_outlined), label: "Invoice"),
+          BottomNavigationBarItem(icon: Icon(Icons.chat_bubble_outline), label: "Chat"),
+          BottomNavigationBarItem(icon: Icon(Icons.settings_outlined), label: "Settings"),
+        ],
+      ),
+    );
+  }
+}