// 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 DefaultTextStyleTransition // //*************************************************************************** //* ▼▼▼▼▼▼▼▼ description ▼▼▼▼▼▼▼▼ (do not modify or remove section marker) // The following code implements the [DefaultTextStyleTransition] that shows // a transition between thick blue font and thin red font. //* ▲▲▲▲▲▲▲▲ 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 AnimationController _controller; late TextStyleTween _styleTween; late CurvedAnimation _curvedAnimation; @override void initState() { super.initState(); _controller = AnimationController( duration: const Duration(seconds: 2), vsync: this, )..repeat(reverse: true); _styleTween = TextStyleTween( begin: const TextStyle( fontSize: 50, color: Colors.blue, fontWeight: FontWeight.w900), end: const TextStyle( fontSize: 50, color: Colors.red, fontWeight: FontWeight.w100), ); _curvedAnimation = CurvedAnimation( parent: _controller, curve: Curves.elasticInOut, ); } @override void dispose() { _controller.dispose(); super.dispose(); } @override Widget build(BuildContext context) { return Center( child: DefaultTextStyleTransition( style: _styleTween.animate(_curvedAnimation), child: const Text('Flutter'), ), ); } //* ▲▲▲▲▲▲▲▲ code ▲▲▲▲▲▲▲▲ (do not modify or remove section marker) //******************************************************************** }