flutter_inset_box_shadow

Description:

flutter inset box shadow

Flutter Inset Box Shadow #
Flutter currently does not support the inset property for shadows. This type of shadow is for example used in Neumorphism.
This package extends BoxShadow and BoxDecoration to support the inset property.
Features #

All properties of BoxShadow are supported.
If the property of a BoxShadow changes during a transition, we first make the old shadow disappear before making the new one appear.

Example #

import 'package:flutter/material.dart' hide BoxDecoration, BoxShadow;
import 'package:flutter_inset_box_shadow/flutter_inset_box_shadow.dart';

void main() {
runApp(const ExampleApp());
}

const primaryColor = Color(0xFFE0E0E0);

class ExampleApp extends StatelessWidget {
const ExampleApp({Key? key}) : super(key: key);

@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Example',
debugShowCheckedModeBanner: false,
home: Scaffold(
backgroundColor: primaryColor,
body: Center(
child: Container(
width: 150,
height: 150,
decoration: BoxDecoration(
borderRadius: BorderRadius.circular(50),
color: primaryColor,
boxShadow: const [
BoxShadow(
offset: Offset(-20, -20),
blurRadius: 60,
color: Colors.white,
inset: true,
),
BoxShadow(
offset: Offset(20, 20),
blurRadius: 60,
color: Color(0xFFBEBEBE),
inset: true,
),
],
),
),
),
),
);
}
}
copied to clipboard
Usage #
First, add the package:
flutter pub add flutter_inset_box_shadow
copied to clipboard
Then, import it as follows:
import 'package:flutter/material.dart' hide BoxDecoration, BoxShadow;
import 'package:flutter_inset_box_shadow/flutter_inset_box_shadow.dart';
copied to clipboard
It is necessary to hide BoxDecoration and BoxShadow because this library replaces them.
BoxShadow now has a boolean inset property, which is set to false by default.
return Container(
decoration: BoxDecoration(
boxShadow: [
BoxShadow(
blurRadius: 5,
color: Colors.red,
),
BoxShadow(
offset: Offset(1, 2),
blurRadius: 5,
spreadRadius: 2,
color: Colors.green,
inset: true,
),
],
),
);
copied to clipboard
How does it work? #
The algorithm used is the same as that of Blink, the Chromium rendering engine.
The idea is that we draw a rectangle hollowed out by another rounded rectangle inside, then we blur this hollowed rectangle.