Flutter（八）：AspectRatio

1实例

AspectRatio 宽高比：

import 'package:flutter/material.dart';

import 'res/listData.dart';

void main() {
  runApp(new MyApp());
}

// 自定义组件
class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    // TODO: implement build
    return MaterialApp(
      // Scaffold 定义导航头部和页面主要内容
      home: Scaffold(
        appBar: AppBar(
          title: Text('flutter 标题'),
        ),
        body: HomePage(),
      ),
      theme: ThemeData(
        primarySwatch: Colors.green,
      ),
    );
  }
}

class HomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Center(
      child: Container(
        width: 300,
        child: AspectRatio(
          aspectRatio: 2 / 1, // 宽高比，依据外层 Container 宽度为 400，则高度为 200
          child: Container(color: Colors.orange),
        ),
      ),
    );
  }
}