使用动画在flutter中单击按钮时创建小部件

import 'package:flutter/material.dart';
import 'package:flutter/animation.dart';

class AnimatedButton extends StatefulWidget {
  @override
  _AnimatedButtonState createState() => _AnimatedButtonState();
}

class _AnimatedButtonState extends State<AnimatedButton>
    with SingleTickerProviderStateMixin {
  AnimationController _animationController;
  Animation<double> _animation;

  @override
  void initState() {
    super.initState();
    _animationController = AnimationController(
      duration: Duration(milliseconds: 500),
      vsync: this,
    );
    _animation = Tween<double>(begin: 1, end: 0.5).animate(_animationController);
  }

  @override
  void dispose() {
    _animationController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return GestureDetector(
      onTap: () {
        if (_animationController.status == AnimationStatus.completed) {
          _animationController.reverse();
        } else {
          _animationController.forward();
        }
      },
      child: AnimatedBuilder(
        animation: _animation,
        builder: (BuildContext context, Widget child) {
          return Transform.scale(
            scale: _animation.value,
            child: RaisedButton(
              child: Text('按钮'),
              onPressed: () {},
            ),
          );
        },
      ),
    );
  }
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('Flutter动画按钮'),
        ),
        body: Center(
          child: AnimatedButton(),
        ),
      ),
    );
  }
}