Flutter -- iOS -- Container

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

void main() =>runApp(
  new MaterialApp(
    title: 'Container布局容器示例',
    home: new LayoutDemo(),
  )
);

class LayoutDemo extends StatelessWidget{
  @override
  Widget build(BuildContext context) {
    // TODO: implement build
    Widget container = new Container(
      decoration: new BoxDecoration(
        color: Colors.grey,
      ),
      child: new Column(
        children: <Widget>[
          new Row(
            children: <Widget>[
              new Expanded(
                child: new Container(
                   150.0,
                  height: 150,
                  decoration: new BoxDecoration(
                    border: new Border.all( 10.0,color: Colors.blueGrey),
                    borderRadius: const BorderRadius.all(const Radius.circular(8.0)),
                  ),
                  margin: const EdgeInsets.all(4.0),
                  child: new Image.asset('images/750-1334-1.png'),
                ),
              ),
              new Expanded(
                  child: new Container(
                     150.0,
                    height: 150.0,
                    decoration: new BoxDecoration(
                      border: new Border.all( 10.0,color: Colors.blueGrey),
                      borderRadius: const BorderRadius.all(const Radius.circular(8.0)),
                    ),
                    margin: const EdgeInsets.all(4.0),
                    child: new Image.asset('images/750-1334-2.png'),
                  ),
              ),
            ],
          ),
          new Row(
            children: <Widget>[
              new Expanded(
                child: new Container(
                   150,
                  height: 150,
                  decoration: new BoxDecoration(
                    border: new Border.all( 10.0,color: Colors.blueGrey),
                    borderRadius: const BorderRadius.all(const Radius.circular(8.0)),
                  ),
                  margin: const EdgeInsets.all(4.0),
                  child: new Image.asset('images/750-1334-3.png'),
                ),
              ),
              new Expanded(
                child: new Container(
                   150,
                  height: 150,
                  decoration: new BoxDecoration(
                    border: new Border.all( 10.0,color: Colors.blueGrey),
                    borderRadius: const BorderRadius.all(const Radius.circular(8.0)),
                  ),
                  margin: const EdgeInsets.all(4.0),
                  child: new Image.asset('images/750-1334-4.png'),
                ),
              ),
            ],
          ),
        ],
      ),
    );
    return new Scaffold(
      appBar: new AppBar(
        title: new Text('appBar显示'),
      ),
      body: container,
    );
  }
}