bool _first = true;
double _width = 200;
double _height = 200;
@override
Widget build(BuildContext context) {
return Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Container(
height: 300,
child: Center(
child: AnimatedSize(
duration: const Duration(milliseconds: 500),
curve: Curves.fastOutSlowIn,
child: Container(
width: _width,
height: _height,
color: Colors.blue,
),
vsync: this,
),
),
),
SizedBox(height: 20,),
RaisedButton(
child: const Text(HIT ME!'),
onPressed: () {
setState(() {
_width = _first ? 220 : 200;
_height = _first ? 160 : 200;
_first = !_first;
});
},
),
],
);
}
