RefreshIndicator

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.purple,
      ),
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {

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

class _MyHomePageState extends State<MyHomePage> {
  int _count = 0;

  Future<Null> _handleRefresh() async{
    await Future.delayed(Duration(seconds: 3));

    setState(() {
      _count = 5;
    });

    return null;
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("HomePage"),
      ),
      body: RefreshIndicator(
        child: new ListView.builder(
          itemCount: _count +4,
          itemBuilder: (context, index){
            return Text("item $index");
          },
        ),
        onRefresh: _handleRefresh,
      ),

    );
  }
}