import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {

  @override

  Widget build(BuildContext context) {

    return MaterialApp(

      home: MyHomePage(),

    );

  }

}

class MyHomePage extends StatefulWidget {

  @override

  _MyHomePageState createState() => _MyHomePageState();

}

class _MyHomePageState extends State<MyHomePage>

    with SingleTickerProviderStateMixin {

  late AnimationController _controller;

  @override

  void initState() {

    _controller = AnimationController(

      duration: const Duration(milliseconds: 5000),

      vsync: this,

    );

    super.initState();

import 'package:flutter/material.dart';

​

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

​

class MyApp extends StatelessWidget {

  @override

  Widget build(BuildContext context) {

    return MaterialApp(

      home: MyHomePage(),

    );

  }

}

​

class MyHomePage extends StatefulWidget {

  @override

  _MyHomePageState createState() => _MyHomePageState();

}

​

class _MyHomePageState extends State<MyHomePage>

    with SingleTickerProviderStateMixin {

  late AnimationController _controller;

​

  @override

  void initState() {

    _controller = AnimationController(

      duration: const Duration(milliseconds: 5000),

      vsync: this,

    );

    super.initState();

  }

​

  @override

  void dispose() {

    _controller.dispose();

    super.dispose();

  }

​

  @override

  Widget build(BuildContext context) {

    return Scaffold(

      appBar: AppBar(

        title: Text("Demo"),

      ),

      body: Center(

        child: Column(

          children: <Widget>[

            RotationTransition(

              turns: Tween(begin: 0.0, end: 1.0).animate(_controller),

              child: Icon(Icons.stars),

            ),

            ElevatedButton(

              child: Text("go"),

              onPressed: () => _controller.forward(),

            ),

            ElevatedButton(

              child: Text("reset"),

              onPressed: () => _controller.reset(),

            ),

          ],

        ),

      ),

    );

  }

}