flutter showBottomSheet 如何设置模糊层
时间: 2024-01-24 12:05:33 浏览: 242
Flutter布局模型之层叠定位
要在Flutter的showBottomSheet中添加模糊层,请按照以下步骤进行操作:
1. 导入BackdropFilter和BlurFilter类:
```
import 'dart:ui';
import 'package:flutter/material.dart';
```
2. 将showBottomSheet方法包装在StatefulWidget中,并在State类中添加一个变量来跟踪是否应该显示模糊层:
```
class MyWidget extends StatefulWidget {
const MyWidget({Key? key}) : super(key: key);
@override
_MyWidgetState createState() => _MyWidgetState();
}
class _MyWidgetState extends State<MyWidget> {
bool _showBlurLayer = false;
void _toggleBlurLayer() {
setState(() {
_showBlurLayer = !_showBlurLayer;
});
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('My App'),
),
body: Center(
child: ElevatedButton(
onPressed: () {
showModalBottomSheet<void>(
context: context,
builder: (BuildContext context) {
return Container(
height: 200.0,
color: Colors.white,
child: Center(
child: Text('This is a modal bottom sheet'),
),
);
},
);
_toggleBlurLayer();
},
child: const Text('Show Modal Bottom Sheet'),
),
),
);
}
}
```
3. 在模态底部表单的构建器中添加一个BackdropFilter小部件,该小部件将一个模糊的图像层应用于其子元素,以创建模糊效果。您可以使用BackDropFilter的filter属性来指定要应用的滤镜,例如BlurFilter:
```
builder: (BuildContext context) {
return BackdropFilter(
filter: ImageFilter.blur(sigmaX: 10.0, sigmaY: 10.0),
child: Container(
height: 200.0,
color: Colors.white,
child: Center(
child: Text('This is a modal bottom sheet'),
),
),
);
},
```
4. 最后,您需要在模态表单关闭时将_showBlurLayer变量设置为false,以便在下一次显示模态表单时不再显示模糊层:
```
Navigator.of(context).pop();
_toggleBlurLayer();
```
这样就可以在Flutter的showBottomSheet中添加模糊层了。
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