Flutter试驾UI篇
首先看下最终的效果
最终效果
那么先从文字下手吧，图片最后实现。
实现标题行
标题行可以拆分为：
- 上线两行的文字(使用Expanded会填充剩余空间)
- 红色五角星icon
- 点赞数量文字
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
Widget titleSection = new Container(
padding: const EdgeInsets.all(32.0),
child: new Row(
children: [
new Expanded(
child: new Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
new Container(
padding: const EdgeInsets.only(bottom: 8.0),
child: new Text(
'Oeschinen Lake Campground',
style: new TextStyle(
fontWeight: FontWeight.bold,
),
),
),
new Text(
'Kandersteg, Switzerland',
style: new TextStyle(
color: Colors.grey[500],
),
),
],
),
),
new Icon(
Icons.star,
color: Colors.red[500],
),
new Text('41'),
],
),
);
//...
}
从上面的分析可以知道吧后面icon和text固定，其他的空间用Expanded填充即可。
按钮行
按钮部分包含三个相同的按钮布局，Flutter和React的思想很类似（借鉴了React的思想）。为了达到复用性和组件化，实现一个按钮，提供设置icon和文字的功能即可。
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
//...
Column buildButtonColumn(IconData icon, String label) {
Color color = Theme.of(context).primaryColor;
return new Column(
mainAxisSize: MainAxisSize.min,
mainAxisAlignment: MainAxisAlignment.center,
children: [
new Icon(icon, color: color),
new Container(
margin: const EdgeInsets.only(top: 8.0),
child: new Text(
label,
style: new TextStyle(
fontSize: 12.0,
fontWeight: FontWeight.w400,
color: color,
),
),
),
],
);
}
//...
}
然后使用这个widget组件实现三个按钮行
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
//...
Widget buttonSection = new Container(
child: new Row(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: [
buildButtonColumn(Icons.call, 'CALL'),
buildButtonColumn(Icons.near_me, 'ROUTE'),
buildButtonColumn(Icons.share, 'SHARE'),
],
),
);
//...
}
实现文本部分
将文本放入容器中，以便沿每条边添加32像素的填充。softwrap属性表示文本是否应在软换行符（例如句点或逗号）之间断开。
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
//...
Widget textSection = new Container(
padding: const EdgeInsets.all(32.0),
child: new Text(
'''
Lake Oeschinen lies at the foot of the Blüemlisalp in the Bernese Alps. Situated 1,578 meters above sea level, it is one of the larger Alpine Lakes. A gondola ride from Kandersteg, followed by a half-hour walk through pastures and pine forest, leads you to the lake, which warms to 20 degrees Celsius in the summer. Activities enjoyed here include rowing, and riding the summer toboggan run.
''',
softWrap: true,
),
);
//...
}
实现上方的图片
body: new ListView(
children: [
new Image.asset(
'images/lake.jpg',
height: 240.0,
fit: BoxFit.cover,
),
// ...
],
)
整合
这些widget使用一个ListView整合在一起。就像android中的scrollView.在小屏幕上显示不下可以滑动。
//...
body: new ListView(
children: [
new Image.asset(
'images/lake.jpg',
width: 600.0,
height: 240.0,
fit: BoxFit.cover,
),
titleSection,
buttonSection,
textSection,
],
),
//...
最后把完整的代码贴下，可以复制运行下
import 'package:flutter/material.dart';
import 'package:flutter/widgets.dart';
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
Widget titleSection = new Container(
padding: const EdgeInsets.all(32.0),
child: new Row(
children: [
new Expanded(
child: new Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
new Container(
padding: const EdgeInsets.only(bottom: 8.0),
child: new Text(
'Oeschinen Lake Campground',
style: new TextStyle(
fontWeight: FontWeight.bold,
),
),
),
new Text(
'Kandersteg, Switzerland',
style: new TextStyle(
color: Colors.grey[500],
),
),
],
),
),
new Icon(
Icons.star,
color: Colors.red[500],
),
new Text('41'),
],
),
);
Column buildButtonColumn(IconData icon, String label) {
Color color = Theme.of(context).primaryColor;
return new Column(
mainAxisSize: MainAxisSize.min,
mainAxisAlignment: MainAxisAlignment.center,
children: [
new Icon(icon, color: color),
new Container(
margin: const EdgeInsets.only(top: 8.0),
child: new Text(
label,
style: new TextStyle(
fontSize: 12.0,
fontWeight: FontWeight.w400,
color: color,
),
),
),
],
);
}
Widget buttonSection = new Container(
child: new Row(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: [
buildButtonColumn(Icons.call, 'CALL'),
buildButtonColumn(Icons.near_me, 'ROUTE'),
buildButtonColumn(Icons.share, 'SHARE'),
],
),
);
Widget textSection = new Container(
padding: const EdgeInsets.all(32.0),
child: new Text(
'''
Lake Oeschinen lies at the foot of the Blüemlisalp in the Bernese Alps. Situated 1,578 meters above sea level, it is one of the larger Alpine Lakes. A gondola ride from Kandersteg, followed by a half-hour walk through pastures and pine forest, leads you to the lake, which warms to 20 degrees Celsius in the summer. Activities enjoyed here include rowing, and riding the summer toboggan run.
''',
softWrap: true,
),
);
return new MaterialApp(
title: 'Flutter Demo',
home: new Scaffold(
appBar: new AppBar(
title: new Text('Top Lakes'),
),
body: new ListView(
children: [
new Image.asset(
'images/lake.jpg',
width: 600.0,
height: 240.0,
fit: BoxFit.cover,
),
titleSection,
buttonSection,
textSection,
],
),
),
);
}
}
void main() {
runApp(new MyApp());
}
