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// 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.
import 'package:flutter/material.dart';
/// Flutter code sample for [FadeTransition].
void main() => runApp(const FadeTransitionExampleApp());
class FadeTransitionExampleApp extends StatelessWidget {
const FadeTransitionExampleApp({super.key});
@override
Widget build(BuildContext context) {
return const MaterialApp(
home: FadeTransitionExample(),
);
}
}
class FadeTransitionExample extends StatefulWidget {
const FadeTransitionExample({super.key});
@override
State<FadeTransitionExample> createState() => _FadeTransitionExampleState();
}
/// [AnimationController]s can be created with `vsync: this` because of
/// [TickerProviderStateMixin].
class _FadeTransitionExampleState extends State<FadeTransitionExample> with TickerProviderStateMixin {
late final AnimationController _controller = AnimationController(
duration: const Duration(seconds: 2),
vsync: this,
)..repeat(reverse: true);
late final Animation<double> _animation = CurvedAnimation(
parent: _controller,
curve: Curves.easeIn,
);
@override
void dispose() {
_controller.dispose();
super.dispose();
}
@override
Widget build(BuildContext context) {
return ColoredBox(
color: Colors.white,
child: FadeTransition(
opacity: _animation,
child: const Padding(padding: EdgeInsets.all(8), child: FlutterLogo()),
),
);
}
}