I am two Lists, List numList and List timeList. Every time I click a button firstly I add 1 to numList and DateTime.now() to timeList.

When I longPress this button, I want a variable on screen to add each value from numList and inBetween wait eah Duration from timeList.

I cant figure out what function should I write, I will attach my code below.

 import 'package:flutter/material.dart';

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

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

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      title: 'Tap Counter',
      debugShowCheckedModeBanner: false,
      home: HomePage(),
    );
  }
}

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

  @override
  State<HomePage> createState() => _HomePageState();
}

class _HomePageState extends State<HomePage> {
  int _counter = 0;
  List<int> _numberList = [];
  List<DateTime> _durationList = [];

  void _onTap() {
    setState(() {
      _counter++;
      _numberList.add(1);
      _durationList.add(DateTime.now());
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          crossAxisAlignment: CrossAxisAlignment.end,
          children: [
            Text('Your Tap Simulation - 0'),
            Text('TapCounter - $_counter'),
          ],
        ),
      ),
      //------------------------------------------------------------------------
      floatingActionButton: InkWell(
        onTap: _onTap,
        onLongPress: () {},
        child: const CircleAvatar(
          radius: 30,
          child: Icon(Icons.add),
        ),
      ),
    );
  }
}

>Solution :

You can try using this method:

  int _tapCount = 0;

  void _simulateTaps() async {
    for (int i = 0; i < _numberList.length; i++) {
      _tapCount += _numberList[i];
      setState(() {
        _tapCount = _tapCount;
      });

      Duration delay = (i < _durationList.length - 1)
          ? _durationList[i + 1].difference(_durationList[i])
          : Duration.zero;

      await Future.delayed(delay);
    }
  }