Using bloc with pageview

main.dart

import 'package:dots_indicator/dots_indicator.dart';
import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';

import 'bloc/intro_bloc.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Intro',
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: BlocProvider(
        create: (context) => IntroBloc(),
        child: IntroWidget(),
      ),
    );
  }
}

class IntroWidget extends StatelessWidget {
  const IntroWidget({
    Key? key,
  }) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: SafeArea(
        child: Stack(
          children: [
            PageView(
              onPageChanged: (index) {
                context.read<IntroBloc>().add(IntroPageChanged(index));
              },
              children: listPages,
            ),
            BlocBuilder<IntroBloc, IntroState>(
              builder: (context, state) {
                print(state.showSkip);
                return Positioned(
                    top: 10,
                    right: 20,
                    child: Visibility(
                      visible: state.showSkip!,
                      child: OutlinedButton(
                        onPressed: () {},
                        child: const Text(
                          'Skip',
                          style: TextStyle(fontSize: 20),
                        ),
                      ),
                    ));
              },
            ),
            Positioned(
              bottom: 80,
              right: 40,
              left: 40,
              child: BlocBuilder<IntroBloc, IntroState>(
                builder: (context, state) {
                  print(state.pageIndex);
                  return DotsIndicator(
                    dotsCount: listPages.length,
                    position: state.pageIndex!,
                  );
                },
              ),
            )
          ],
        ),
      ),
    );
  }
}


//List of pages 
final listPages = [
  const PageOne(),
  const PageTwo(),
  const PageThree(),
];

class PageOne extends StatelessWidget {
  const PageOne({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Text('Page one'),
    );
  }
}

class PageTwo extends StatelessWidget {
  const PageTwo({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Text('Page one'),
    );
  }
}

class PageThree extends StatelessWidget {
  const PageThree({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Text('Page one'),
    );
  }
}

//Intro Bloc
import 'package:bloc/bloc.dart';
import 'package:meta/meta.dart';

part 'intro_event.dart';
part 'intro_state.dart';

class IntroBloc extends Bloc<IntroEvent, IntroState> {
  IntroBloc() : super(IntroState.initial());

  @override
  Stream<IntroState> mapEventToState(
    IntroEvent event,
  ) async* {
    if (event is IntroPageChanged) {
      yield state.copyWith(
        pageIndex: event.pageIndex.toDouble(),

        //2 represent total no of pages -1
        //Since index of List starts from 0
        showSkip: event.pageIndex == 2,
      );
    }
  }
}


// IntroBloc state
part of 'intro_bloc.dart';

class IntroState {
  final double? pageIndex;

  final bool? showSkip;

  const IntroState({this.pageIndex, this.showSkip});

  static IntroState initial() {
    return const IntroState(
      pageIndex: 0,
      showSkip: false,
    );
  }

  IntroState copyWith({double? pageIndex, bool? showSkip}) {
    return IntroState(
      pageIndex: pageIndex,
      showSkip: showSkip,
    );
  }
}

//IntroBloc event

part of 'intro_bloc.dart';

@immutable
abstract class IntroEvent {}

class IntroPageChanged extends IntroEvent {
  final int pageIndex;

  IntroPageChanged(this.pageIndex);
}