我想使容器具有两种不同的不透明度,以使屏幕更专注于某些图像,我使用了堆栈和容器,是否可以制作这样的东西?
这是我的代码示例,
Stack(
children: <Widget>[
Image(),
Container(
height: double.infinity,
width: double.infinity,
color: Colors.black.withOpacity(0.4),
),
感谢大家,
我不确定这是否是很好的解决方案。它将解决问题。
import 'package:flutter/material.dart';
void main() => runApp(MaterialApp(home: FirstPage()));
class FirstPage extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text("Demo")),
body: Stack(
fit: StackFit.expand,
children: <Widget>[
Image.network(
"https://images.pexels.com/photos/414612/pexels-photo-414612.jpeg",
fit: BoxFit.cover,
),
CustomPaint(
painter: MyPainter(),
)
],
),
);
}
}
class MyPainter extends CustomPainter {
final Color color;
final double opacity;
final double radius;
MyPainter({Color color, double opacity, double radius})
: color = color ?? Colors.black,
radius = radius ?? 0.3,
opacity = opacity ?? 0.4;
@override
void paint(Canvas canvas, Size size) {
var rect = Offset.zero & size;
var gradient = RadialGradient(
center: Alignment.center,
radius: radius,
colors: [const Color(0x0000000), color.withOpacity(opacity)],
stops: [1.0, 1.0],
);
canvas.drawRect(
rect,
Paint()..shader = gradient.createShader(rect),
);
}
@override
bool shouldRepaint(CustomPainter oldDelegate) {
return false;
}
}