如何在颤动中填充 2 个圆圈之间的空间？

问题描述

我的圈子画家：

    CircleWavePainter(this.animationValue) {
//add some property to paint
  wavePaint = Paint()
    ..color = Colors.black.withAlpha(100)
    ..style = PaintingStyle.stroke
    ..strokeWidth = 1
    ..isAntiAlias = true;
}

我的颜料画了 2 个圆圈，需要一些帮助来填充空间：

void paint(Canvas canvas,Size size) {
//circle 1
canvas.drawCircle(Offset(size.height / 2,size.width / 2),80 * (1.4 - animationValue / 2),wavePaint);
//circle 2    
canvas.drawCircle(Offset(size.height / 2,80 * (1.8 - animationValue / 2),wavePaint);
}

解决方法

你可以使用 stack Widget 我在我的课程中没有接触到动画，但我可以给你一个提示

Stack(
        alignment: AlignmentDirectional.bottomEnd,children: [
          CircleAvatar(
            radius: 30,backgroundImage: NetworkImage(
              'https://thispersondoesnotexist.com/image',),//photo
          CircleAvatar(
            radius: 7,backgroundColor: Colors.white,// active or not
          CircleAvatar(
            radius: 6,backgroundColor: Colors.green,// active circle space
        ],)

,

使用“堆栈”小部件而不是“绘制”来实现您的设计。

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',theme: ThemeData(
        primarySwatch: Colors.blue,visualDensity: VisualDensity.adaptivePlatformDensity,home: MyHomePage(title: 'Flutter Demo Home Page'),);
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key,this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  @override
  void initState() {
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),body: _buildBody(),);
  }

  Widget _buildBody() {
    return Container(
      height: 400,width: 400,child: Stack(
        alignment: AlignmentDirectional.center,children: [
          Container(
            width: 280,height: 280,decoration: BoxDecoration(
              shape: BoxShape.circle,color: Color(0xFF4C4D4F),Container(
            width: 200,height: 200,color: Colors.white,Container(
            width: 140,height: 140,child: Icon(
              Icons.access_alarm,size: 30,color: Color(0xFF5EA2EB),)
        ],);
  }
}