Flutter之Decoration
1、不废话,先爆照看效果
2、Decoration介绍
Flutter的Decoration可以设置:背景色 背景图 边框 圆角 阴影 渐变色 的等属性,有点像android里面的shape,Decoration 是基类,它的子类有下面这些
BoxDecoration:实现边框、圆角、阴影、形状、渐变、背景图像
ShapeDecoration:实现四边分别指定颜色和宽度、底部线、矩形边色、圆形边色、体育场(竖向椭圆)、 角形(八边角)边色
FlutterLogoDecoration:Flutter图片
UnderlineTabindicator:下划线
这里先介绍常用的 BoxDecoration,构造方法
const BoxDecoration({
this.color,//背景色
this.image,//图片
this.border,//描边
this.borderRadius,//圆角大小
this.boxShadow,//阴影
this.gradient,//渐变色
this.backgroundBlendMode,//图像混合模式
this.shape = BoxShape.rectangle,//形状,BoxShape.circle和borderRadius不能同时使用
})
boxShadow 阴影
color - 阴影颜色
offset - 阴影相偏移量
blurRadius - 高斯模糊数值
spreadRadius - 阴影膨胀量,这个值我是真不知有啥用,没场景啊,一般不写这个值
gradient渐变
支持2种渐变:LinearGradient线性渐变 和 RadialGradient扫描渐变
LinearGradient :
begin - 渐变开始的位置
end - 渐变结束的位置
colors - 渐变颜色,是数组
stops - 值列表,装有0.0到1.0的数值
tileMode - 平铺模式
shape形状
rectangle是矩形,BoxShape.circle是圆形,BoxShape.circle和borderRadius不能一起使用
3、代码测试
效果1测试代码
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'open url',
home: Scaffold(
appBar: AppBar(
// Here we take the value from the MyHomePage object that was created by
// the App.build method, and use it to set our appbar title.
title: Text('hello flutter'),
),
body: Center(
child: DecoratedBox(
// padding: EdgeInsets.all(16),
// padding: EdgeInsets.fromLTRB(10, 20, 30, 40),
// padding: EdgeInsets.only(left: 10, right: 30),
decoration: BoxDecoration(
// 背景色
color: Colors.lightBlueAccent,
// 边框,
border: Border.all(color: Colors.yellowAccent, style: BorderStyle.solid, width: 5),
// 背景图
image: new DecorationImage(
image: new NetworkImage(
'https://ss0.bdstatic.com/70cFvHSh_Q1YnxGkpoWK1HF6hhy/it/u=1484037605,2864708693&fm=11&gp=0.jpg'),
fit: BoxFit.cover
),
borderRadius: BorderRadius.all(Radius.circular(30)),
boxShadow:[
BoxShadow(
color: Colors.redAccent,
offset: Offset(20, 20),
blurRadius: 10,
),
]
),
child: Container(
height: 200,
width: 200,
),
),
),
),
);
}
}
效果2测试代码
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'open url',
home: Scaffold(
appBar: AppBar(
// Here we take the value from the MyHomePage object that was created by
// the App.build method, and use it to set our appbar title.
title: Text('hello flutter'),
),
body: Center(
child: DecoratedBox(
// padding: EdgeInsets.all(16),
// padding: EdgeInsets.fromLTRB(10, 20, 30, 40),
// padding: EdgeInsets.only(left: 10, right: 30),
decoration: BoxDecoration(
// 背景色
gradient: LinearGradient(colors:[Colors.blue, Colors.green]), //背景渐变
color: Colors.lightBlueAccent,
// 背景图
borderRadius: BorderRadius.all(Radius.circular(3)),
boxShadow: [ //阴影
BoxShadow(
color:Colors.black54,
offset: Offset(2.0,2.0),
blurRadius: 4.0
)
]
),
child: Padding(
padding: EdgeInsets.symmetric(horizontal: 80.0, vertical: 18.0),
child: Text("chenyu", style: TextStyle(color: Colors.white),
),
)
),
),
),
);
}
}
效果3测试代码
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'open url',
home: Scaffold(
appBar: AppBar(
// Here we take the value from the MyHomePage object that was created by
// the App.build method, and use it to set our appbar title.
title: Text('hello flutter'),
),
body: Center(
child: DecoratedBox(
// padding: EdgeInsets.all(16),
// padding: EdgeInsets.fromLTRB(10, 20, 30, 40),
// padding: EdgeInsets.only(left: 10, right: 30),
decoration: BoxDecoration(
// 背景色
border: Border.all(
color: Colors.yellowAccent, style: BorderStyle.solid, width: 5),
// 背景图
image: new DecorationImage(
image: new NetworkImage(
'https://ss0.bdstatic.com/70cFvHSh_Q1YnxGkpoWK1HF6hhy/it/u=1484037605,2864708693&fm=11&gp=0.jpg'),
fit: BoxFit.cover
),
shape: BoxShape.circle,
),
child: Container(
width: 200,
height: 200,
),
),
),
),
);
}
}
作者:chen.yu
深信服三年半工作经验,目前就职游戏厂商,希望能和大家交流和学习,
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