Auto-generated Widgets

main.dart

// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

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

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;
  var _generatedWidgets = <Widget>[];
  bool _isGenerating = false;

  void _toggleGenerator() {
    _isGenerating = !_isGenerating;
    _generator();
  }

  void _generator() async {
    while (_isGenerating) {
      await Future.delayed(Duration(seconds: 1));
      setState(() {
        _generatedWidgets.add(Text("${_counter++} I'm a generated Widget!"));
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: ListView(children: <Widget>[
        Text(
          'There are $_counter widgets generated',
        ),
        ..._generatedWidgets
      ]),
      floatingActionButton: FloatingActionButton(
        onPressed: _toggleGenerator,
        tooltip: 'Generate',
        child: Icon(Icons.add),
      ),
    );
  }
}