refresh_indicator.0.dart

// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Flutter code sample for RefreshIndicator

import 'package:flutter/material.dart';

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

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

  static const String _title = 'RefreshIndicator Sample';

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      title: _title,
      home: RefreshIndicatorExample(title: _title),
    );
  }
}

class RefreshIndicatorExample extends StatefulWidget {
  const RefreshIndicatorExample({Key? key, required this.title}) : super(key: key);

  final String title;

  @override
  State<RefreshIndicatorExample> createState() => _RefreshIndicatorExampleState();
}

class _RefreshIndicatorExampleState extends State<RefreshIndicatorExample> {
  final GlobalKey<RefreshIndicatorState> _refreshIndicatorKey =
    GlobalKey<RefreshIndicatorState>();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: RefreshIndicator(
        key: _refreshIndicatorKey,
        color: Colors.white,
        backgroundColor: Colors.blue,
        strokeWidth: 4.0,
        onRefresh: () async {
          // Replace this delay with the code to be executed during refresh
          // and return a Future when code finishs execution.
          return Future<void>.delayed(const Duration(seconds: 3));
        },
        // Pull from top to show refresh indicator.
        child: ListView.builder(
          itemCount: 25,
          itemBuilder: (BuildContext context, int index) {
            return ListTile(
              title: Text('Item $index'),
            );
          },
        ),
      ),
      floatingActionButton: FloatingActionButton.extended(
        onPressed: () {
          // Show refresh indicator programmatically on button tap.
          _refreshIndicatorKey.currentState?.show();
        },
        icon: const Icon(Icons.refresh),
        label: const Text('Show Indicator'),
      ),
    );
  }
}