error assets

import 'package:flutter/material.dart';
import 'package:smart_relay/theme.dart';
import 'home_page.dart';

class MainPage extends StatefulWidget {
  @override
  State<MainPage> createState() => _MainPageState();
}

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

  @override
  Widget build(BuildContext context) {
    Widget customBottomNav() {
      return ClipRRect(
        borderRadius: BorderRadius.vertical(
          top: Radius.circular(30),
        ),
        child: BottomAppBar(
          shape: CircularNotchedRectangle(),
          notchMargin: 12,
          clipBehavior: Clip.antiAlias,
          child: BottomNavigationBar(
            backgroundColor: backgroundColor4,
            currentIndex: currentIndex,
            onTap: (value) {
              setState(() {
                currentIndex = value;
              });
            },
            type: BottomNavigationBarType.fixed,
            items: [
              BottomNavigationBarItem(
                icon: Container(
                  margin: const EdgeInsets.only(
                    top: 20,
                    bottom: 10,
                  ),
                  child: Image.asset(
                    'assets/icon_home.png',
                    width: 21,
                    color: currentIndex == 0 ? primaryColor : Color(0xff808191),
                  ),
                ),
                label: '',
              ),
              BottomNavigationBarItem(
                icon: Container(
                  margin: EdgeInsets.only(
                    top: 20,
                    bottom: 10,
                  ),
                  child: Image.asset(
                    'assets/icon_home.png',
                    width: 18,
                    color: currentIndex == 3 ? primaryColor : Color(0xff808191),
                  ),
                ),
                label: '',
              ),
            ],
          ),
        ),
      );
    }

    Widget body() {
      switch (currentIndex) {
        case 0:
          return HomePage();
        // case 1:
        //   return ChatPage();
        // case 2:
        //   return WishlistPage();
        // case 3:
        //   return ProfilePage();

        default:
          return HomePage();
      }
      ;
    }

    return Scaffold(
      backgroundColor: currentIndex == 0 ? backgroundColor1 : backgroundColor3,
      // floatingActionButton: cartButton(),
      floatingActionButtonLocation: FloatingActionButtonLocation.centerDocked,
      bottomNavigationBar: customBottomNav(),
      body: body(),
    );
  }
}