12Flutter页面布局 AspectRatio和Cart卡片组件

/*

Flutter AspectRatio、Cart卡片组件：

AspectRatio的作用是根据设置调整子元素child的宽高比。

AspectRatio首先会在布局限制条件允许的范围内尽可能的扩展，widget的高度是由宽度和比率决定的。

类似于BoxFit中的contain,按照固定比率去尽量占满区域。

如果在满足所有限制条件过后无法找到一个可行的尺寸，AspectRatio最终将会去优先适应布局限制条件，而忽略所设置的比率。

*/

main.dart

import 'package:flutter/material.dart';
void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    // TODO: implement build
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text(' AspectRatio、Cart卡片组件'),
        ),
        body: HomeContent(),
      ),
    );
  }
}

class HomeContent extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    //Stack结合align实现布局：
    return AspectRatio(
      aspectRatio: 2.0/1.0,
      child: Container(
        color: Colors.red,
      ),
    );
  }
}

Cart卡片组件：

demo1:

main.dart

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    // TODO: implement build
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text(' AspectRatio、Cart卡片组件'),
        ),
        body: HomeContent(),
      ),
    );
  }
}

class HomeContent extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    //Stack结合align实现布局：
    return ListView(
      children: <Widget>[
        Card(
          child: Column(
            children: <Widget>[
              ListTile(title: Text('中国'), subtitle: Text('山东')),
              ListTile(
                title: Text('青岛'),
              ),
              ListTile(
                title: Text('烟台'),
              )
            ],
          ),
        ),
        Card(
          child: Column(
            children: <Widget>[
              ListTile(title: Text('中国'), subtitle: Text('山东')),
              ListTile(
                title: Text('青岛'),
              ),
              ListTile(
                title: Text('烟台'),
              )
            ],
          ),
        )
      ],
    );
  }
}

demo2:

main.dat

import 'package:flutter/material.dart';


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



class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    // TODO: implement build
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text(' AspectRatio、Cart卡片组件'),
        ),
        body: HomeContent(),
      ),
    );
  }
}



class HomeContent extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    //Stack结合align实现布局：
    return ListView(
      children: <Widget>[
        Card(
          margin: EdgeInsets.all(10),
          child: Column(
            children: <Widget>[
              AspectRatio(
                aspectRatio: 16 / 9,
                child: Image.network(
                    'https://www.itying.com/images/flutter/1.png',fit: BoxFit.cover),
              ),
              ListTile(
                  leading: ClipOval(
                    child: Image.network('https://www.itying.com/images/flutter/1.png',fit: BoxFit.cover, 50,height: 50),
                  ),
                  title: Text('data'),
                  subtitle: Text('data'))
            ],
          ),
        ),
        Card(
          margin: EdgeInsets.all(10),
          child: Column(
            children: <Widget>[
              AspectRatio(
                aspectRatio: 16 / 9,
                child: Image.network(
                    'https://www.itying.com/images/flutter/1.png',fit: BoxFit.cover),
              ),
              ListTile(
                  leading: CircleAvatar(
                    backgroundImage: NetworkImage(
                        'https://www.itying.com/images/flutter/1.png'),
                  ),
                  title: Text('data'),
                  subtitle: Text('data'))
            ],
          ),
        )
      ],
    );
  }
}

 demo3:

main.dart

import 'package:flutter/material.dart';
import 'res/listData.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    // TODO: implement build
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text(' AspectRatio、Cart卡片组件'),
        ),
        body: HomeContent(),
      ),
    );
  }
}

class HomeContent extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    //Stack结合align实现布局：
    return ListView(
      children: listData.map((value) {
        return Card(
          margin: EdgeInsets.all(10),
          child: Column(
            children: <Widget>[
              AspectRatio(
                aspectRatio: 16 / 9,
                child: Image.network(
                    "${value['imageUrl']}",
                    fit: BoxFit.cover),
              ),
              ListTile(
                  leading: CircleAvatar(
                    backgroundImage: NetworkImage(
                        "${value['imageUrl']}"),
                  ),
                  title: Text("${value['title']}"),
                  subtitle: Text("${value['descripts']}",maxLines:2,overflow: TextOverflow.ellipsis,))
            ],
          ),
        );
      }).toList(),
    );
  }
}

listData.dart

List listData=[
  {
    "title":"Candy Shop",
    "author":"Mohamed Chahin",
    "imageUrl":"https://www.itying.com/images/flutter/1.png",
    "descripts":"MohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahin"
  },
  {
    "title":"Candy Shop",
    "author":"Mohamed Chahin",
    "imageUrl":"https://www.itying.com/images/flutter/2.png",
    "descripts":"MohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahin"
  
  },
  {
    "title":"Candy Shop",
    "author":"Mohamed Chahin",
    "imageUrl":"https://www.itying.com/images/flutter/3.png",
    "descripts":"MohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahin"
  
  },
  {
    "title":"Candy Shop",
    "author":"Mohamed Chahin",
    "imageUrl":"https://www.itying.com/images/flutter/4.png",
    "descripts":"MohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahin"
  
  },{
    "title":"Candy Shop",
    "author":"Mohamed Chahin",
    "imageUrl":"https://www.itying.com/images/flutter/5.png",
    "descripts":"MohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahinMohamedChahin"
  
  }
];