Animation - AnimatedWidget

 AnimatedWidget

Source Code

import 'package:flutter/material.dart';

void main() {
  runApp(  MaterialApp(
    title:" Animation ",
    home:Scaffold(appBar: AppBar(title: Text(' Animation ',),),
      body: Material(
        child: Center(
          child:
          AnimatedWidgetExample()
          ,
        ),
      ) ,
    ),
  ));
}



class _AnimatedLogo extends AnimatedWidget {
  const _AnimatedLogo({Key? key, required Animation<double> animation})
      : super(key: key, listenable: animation);

  @override
  Widget build(BuildContext context) {
    final Animation<double> animation = this.listenable as Animation<double>;
    return Center(
      child: Container(
        margin: const EdgeInsets.all(8.0),
        height: animation.value,
        width: animation.value,
        child: const FlutterLogo(),
      ),
    );
  }
}

class AnimatedWidgetExample extends StatefulWidget {
  const AnimatedWidgetExample({Key? key}) : super(key: key);
  @override
  _AnimatedWidgetExampleState createState() => _AnimatedWidgetExampleState();
}

class _AnimatedWidgetExampleState extends State<AnimatedWidgetExample>
    with SingleTickerProviderStateMixin {
  late Animation<double> _sizeAnimation;
  late AnimationController _controller;

  @override
  void initState() {
    super.initState();
    this._controller =
        AnimationController(duration: const Duration(seconds: 1), vsync: this);
    this._sizeAnimation =
        Tween<double>(begin: 50, end: 100).animate(this._controller);
  }

  @override
  void dispose() {
    super.dispose();
    this._controller.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Column(
      children: <Widget>[
        _AnimatedLogo(
          animation: this._sizeAnimation,
        ),
        ElevatedButton(
          onPressed: () => _controller.forward(),
          child: const Text('Forward animation'),
        ),
        ElevatedButton(
          onPressed: () => _controller.reverse(),
          child: const Text('Reverse animation'),
        ),
      ],
    );
  }
}