Rive icons not showing

Question

I am new to flutter and have no idea about it, I created a bottom bar and icons are rive tried to run on flutter app, but the icons are not showing up. This is my code

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:hlibrary/models/tab_item.dart';
import 'package:rive/rive.dart' hide LinearGradient;

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

  @override
  State<BotBar> createState() => _BotBarState();
}

class _BotBarState extends State<BotBar> {
  final List<TabItem> _icons = TabItem.tabItemsList;
  int _selectedTab = 0;

  void _onRiveIconInit(Artboard artboard, index) {
    final controller = StateMachineController.fromArtboard(
        artboard, _icons[index].stateMachine);
    artboard.addController(controller!);

    _icons[index].status = controller.findInput<bool>("active") as SMIBool;
  }

  void onTabPress(int index) {
    if (_selectedTab != index) {
      setState(() {
        _selectedTab = index;
      });
      _icons[index].status!.change(true);
      Future.delayed(const Duration(seconds: 1), () {
        _icons[index].status!.change(true);
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    return SafeArea(
      child: Container(
        decoration: BoxDecoration(
          gradient: LinearGradient(colors: [
            Colors.white.withOpacity(0.5),
            Colors.white.withOpacity(0)
          ]),
        ),
        child: Container(
          decoration: const BoxDecoration(
              boxShadow: [
                BoxShadow(color: Colors.amber, offset: Offset(0, 20))
              ],
              color: Color.fromARGB(0, 255, 255, 255),
              borderRadius: BorderRadius.only(
                  topLeft: Radius.circular(15), topRight: Radius.circular(15))),
          child: Row(
            mainAxisAlignment: MainAxisAlignment.spaceEvenly,
            children: List.generate(_icons.length, (index) {
              TabItem icon = _icons[index];
              return Expanded(
                key: icon.id,
                child: CupertinoButton(
                  padding: const EdgeInsets.all(12),
                  child: AnimatedOpacity(
                    opacity: _selectedTab == index ? 1 : 0.5,
                    duration: const Duration(milliseconds: 200),
                    child: Stack(
                        clipBehavior: Clip.none,
                        alignment: Alignment.center,
                        children: [
                          Positioned(
                            top: -4,
                            child: AnimatedContainer(
                              duration: const Duration(milliseconds: 200),
                              height: 4,
                              width: _selectedTab == index ? 20 : 0,
                              decoration: BoxDecoration(
                                  color: Colors.blue,
                                  borderRadius: BorderRadius.circular(2)),
                            ),
                          ),
                          SizedBox(
                            height: 36,
                            width: 36,
                            child: RiveAnimation.asset(
                              'assets/rive/icons.riv',
                              stateMachines: const ["icon.stateMachine"],
                              artboard: "_icon.artboard",
                              onInit: (artboard) {
                                _onRiveIconInit(artboard, index);
                              },
                            ),
                          ),
                        ]),
                  ),
                  onPressed: () {
                    onTabPress(index);
                  },
                ),
              );
            }),
          ),
        ),
      ),
    );
  }
}

import 'package:flutter/material.dart';
import 'package:rive/rive.dart';

class TabItem {
  TabItem({
    this.stateMachine = "",
    this.artboard = "",
    this.status,
  });
  UniqueKey? id = UniqueKey();
  String stateMachine;
  String artboard;
  late SMIBool? status;

  static List<TabItem> tabItemsList = [
    TabItem(stateMachine: "HOME_Interactivity", artboard: "HOME"),
    TabItem(stateMachine: "STAR_Interactivity", artboard: "STAR"),
    TabItem(stateMachine: "USER_Interactivity", artboard: "USER"),
    TabItem(stateMachine: "SETTINGS_Interactivity", artboard: "SETTINGS"),
  ];
}

In debug console says this and app pauses but when I try co continue it pauses again 5 or 6 times then it works, but icons are not showing upenter image description here