Explicit Animations - RotationTransition

main.dart

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: MyHomePage(),
    );
  }
}

const double _logoSize = 200.0;

class OtusLogo extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      child: Image.network('https://github.com/flutter-cats/otus-cocktails-application/blob/master/logo-2.8602b.svg'),
      width: _logoSize,
      height: _logoSize,
      color: Colors.green,
    );
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage>
    with SingleTickerProviderStateMixin {
  AnimationController _controller;

  @override
  void initState() {
    super.initState();
    _controller = AnimationController(
      vsync: this,
      duration: const Duration(seconds: 1),
    );
  }

  void dispose() {
    _controller.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Explicit Animations - RotationTransition'),
      ),
      body: Center(
        child: Container(
          height: 300,
          child: Stack(
            children: <Widget>[
              RotationTransition(
                turns: _controller,
                child: OtusLogo(),
              ),
            ],
          ),
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: () {
          if (_controller.isAnimating) {
            _controller.stop();
          } else {
            _controller.repeat();
          }

          setState(() {});
        },
        child:
            _controller.isAnimating ? Icon(Icons.stop) : Icon(Icons.play_arrow),
      ),
    );
  }
}