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

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'List playground',
      home: TestPage(),
    );
  }
}

class TestPage extends StatefulWidget {
  @override
  State<StatefulWidget> createState() => _TestPageState();
}

class _TestPageState extends State<TestPage> {
  List<String> items = ['1', '2', '3', '4', '5'];
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: SizedBox(
          width: 44.4,
          height: 30.0,
          child: Directionality(
            textDirection: TextDirection.ltr,
            child: CustomScrollView(
              slivers: <Widget>[
                SliverFixedExtentList(
                  itemExtent: 22.2,
                  delegate: SliverChildBuilderDelegate(
                      (BuildContext context, int index) {
                      return TextWidget(
                        items[index],
                      );
                    },
                    childCount : items.length,
                  ),
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }
}
class TextWidget extends StatefulWidget {
  const TextWidget(this.data);
  final String data;


  @override
  TextWidgetState createState() => TextWidgetState();
}

class TextWidgetState extends State<TextWidget>{

  @override
  void dispose() {
    print('disposed ${widget.data}');
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Text(widget.data);
  }
}