// 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. // Template: dev/snippets/config/templates/stateful_widget_material_ticker.tmpl // // Comment lines marked with "▼▼▼" and "▲▲▲" are used for authoring // of samples, and may be ignored if you are just exploring the sample. // Flutter code sample for SizeTransition // //*************************************************************************** //* ▼▼▼▼▼▼▼▼ description ▼▼▼▼▼▼▼▼ (do not modify or remove section marker) // This code defines a widget that uses [SizeTransition] to change the size // of [FlutterLogo] continually. It is built with a [Scaffold] // where the internal widget has space to change its size. //* ▲▲▲▲▲▲▲▲ description ▲▲▲▲▲▲▲▲ (do not modify or remove section marker) //*************************************************************************** import 'package:flutter/material.dart'; void main() => runApp(const MyApp()); /// This is the main application widget. class MyApp extends StatelessWidget { const MyApp({Key? key}) : super(key: key); static const String _title = 'Flutter Code Sample'; @override Widget build(BuildContext context) { return const MaterialApp( title: _title, home: MyStatefulWidget(), ); } } /// This is the stateful widget that the main application instantiates. class MyStatefulWidget extends StatefulWidget { const MyStatefulWidget({Key? key}) : super(key: key); @override State<MyStatefulWidget> createState() => _MyStatefulWidgetState(); } /// This is the private State class that goes with MyStatefulWidget. /// AnimationControllers can be created with `vsync: this` because of TickerProviderStateMixin. class _MyStatefulWidgetState extends State<MyStatefulWidget> with TickerProviderStateMixin { //******************************************************************** //* ▼▼▼▼▼▼▼▼ code ▼▼▼▼▼▼▼▼ (do not modify or remove section marker) late final AnimationController _controller = AnimationController( duration: const Duration(seconds: 3), vsync: this, )..repeat(); late final Animation<double> _animation = CurvedAnimation( parent: _controller, curve: Curves.fastOutSlowIn, ); @override void dispose() { super.dispose(); _controller.dispose(); } @override Widget build(BuildContext context) { return Scaffold( body: SizeTransition( sizeFactor: _animation, axis: Axis.horizontal, axisAlignment: -1, child: const Center( child: FlutterLogo(size: 200.0), ), ), ); } //* ▲▲▲▲▲▲▲▲ code ▲▲▲▲▲▲▲▲ (do not modify or remove section marker) //******************************************************************** }