flutter stepper

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(title: Text('Flutter Stepper Example')),
        body: StepperExample(),
      ),
    );
  }
}

class StepperExample extends StatefulWidget {
  @override
  _StepperExampleState createState() => _StepperExampleState();
}

class _StepperExampleState extends State<StepperExample> {
  int currentStep = 0;
  static const TextStyle headingStyle = TextStyle(fontSize: 20, fontWeight: FontWeight.bold);

  @override
  Widget build(BuildContext context) {
    return Column(
      children: <Widget>[
        Expanded(
          child: Stepper(
            currentStep: currentStep,
            onStepContinue: () {
              setState(() {
                if (currentStep < 2) {
                  currentStep++;
                }
              });
            },
            onStepCancel: () {
              setState(() {
                if (currentStep > 0) {
                  currentStep--;
                }
              });
            },
            steps: [
              Step(
                title: Text('Step 1', style: headingStyle),
                content: Text('This is the first step'),
              ),
              Step(
                title: Text('Step 2', style: headingStyle),
                content: Text('This is the second step'),
              ),
              Step(
                title: Text('Step 3', style: headingStyle),
                content: Text('This is the third step'),
              ),
            ],
          ),
        ),
      ],
    );
  }
}

onStepContinue: () {
  if (validateStep(currentStep)) {
    setState(() {
      if (currentStep < 2) {
        currentStep++;
      }
    });
  } else {
    // Show error message
  }
},