DART

Stack Container flutter

class StackExample extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(),
      body:  new Container(
        padding: const EdgeInsets.all(8.0),
          height: 500.0,
          width: 500.0,
          // alignment: FractionalOffset.center,
          child: new Stack(
            //alignment:new Alignment(x, y)
            children: <Widget>[
              new Icon(Icons.monetization_on, size: 36.0, color: const Color.fromRGBO(218, 165, 32, 1.0)),
              new Positioned(
                left: 20.0,
                child: new Icon(Icons.monetization_on, size: 36.0, color: const Color.fromRGBO(218, 165, 32, 1.0)),
              ),
              new Positioned(
                left:40.0,
                child: new Icon(Icons.monetization_on, size: 36.0, color: const Color.fromRGBO(218, 165, 32, 1.0)),
              )

            ],
          ),
        ),
      )
    ;
  }
}

flutter stack

Stack(
  children: <Widget>[
    Container(
      width: 290,
      height: 190,
      color: Colors.green,
    ),
    Container(
      width: 250,
      height: 170,
      color: Colors.red,
    ),
    Container(
      width: 220,
      height: 150,
      color: Colors.yellow,
    ),
  ],
)