import 'dart:math';

import 'package:flutter/material.dart';

void main() {
  runApp(MaterialApp(
      home: Scaffold(
    appBar: AppBar(
      title: Text("SabaTest"),
    ),
    body: IndicatorPager(),
  )));
}

class IndicatorPager extends StatefulWidget {
  @override
  _IndicatorPagerState createState() => _IndicatorPagerState();
}

class _IndicatorPagerState extends State<IndicatorPager> {
  final List<Widget> _numbers = List.generate(10, _generatePages);
  int _currentPage = 0;

  @override
  Widget build(BuildContext context) {
    return Stack(
      children: <Widget>[
        Padding(
          padding: const EdgeInsets.all(16.0),
          child: ProgressWidget(_currentPage, _numbers.length),
        ),
        PageView(
          onPageChanged: (newPage) => setState(() {
                _currentPage = newPage;
              }),
          children: _numbers,
        ),
      ],
    );
  }
}

Widget _generatePages(int index) {
  return Center(child: Text(index.toString()));
}

class ProgressWidget extends StatelessWidget {
  final int _progress;
  final int _total;

  const ProgressWidget(this._progress, this._total, {Key key})
      : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Row(
      children: _getProgress(context),
    );
  }

  List<Widget> _getProgress(context) {
    List<Widget> list = [];
    for (int i = 0; i < _total; i++) {
      list.add(Flexible(
        flex: 5,
        child: Container(
          height: 5,
          decoration: BoxDecoration(
              color: i < _progress
                  ? Theme.of(context).accentColor
                  : Colors.grey[100],
              borderRadius: BorderRadius.circular(20),
              boxShadow: <BoxShadow>[
                BoxShadow(
                  offset: Offset(1, 1),
                  blurRadius: 3.0,
                )
              ]),
        ),
      ));

      if (i < _total - 1) {
        list.add(Spacer());
      }
    }
    return list;
  }
}