import 'dart:ui'; import 'package:flutter/material.dart'; import '../components/coordinate_pro.dart'; /// create by 张风捷特烈 on 2020/5/1 /// contact me by email 1981462002@qq.com /// 说明: class Paper extends StatelessWidget { const Paper({super.key}); @override Widget build(BuildContext context) { return Container( color: Colors.white, child: CustomPaint( // 使用CustomPaint painter: PaperPainter(), ), ); } } class PaperPainter extends CustomPainter { final Coordinate coordinate = Coordinate(); Paint _helpPaint = Paint(); double waveWidth = 80; double wrapHeight =100; double waveHeight = 40; @override void paint(Canvas canvas, Size size) { coordinate.paint(canvas, size); canvas.translate(size.width / 2, size.height / 2); Path path = Path(); Paint paint = Paint() ..color = Colors.orange ..style = PaintingStyle.stroke ..strokeWidth = 2; canvas.save(); canvas.translate(-2*waveWidth, 0); path.moveTo(0, 0); path.relativeQuadraticBezierTo(waveWidth/2, -waveHeight*2, waveWidth, 0); path.relativeQuadraticBezierTo(waveWidth/2, waveHeight*2, waveWidth, 0); path.relativeQuadraticBezierTo(waveWidth/2, -waveHeight*2, waveWidth, 0); path.relativeQuadraticBezierTo(waveWidth/2, waveHeight*2, waveWidth, 0); path.close(); canvas.drawPath(path, paint..style=PaintingStyle.fill); canvas.restore(); _drawHelp(canvas); } void _drawHelp(Canvas canvas) { _helpPaint ..color = Colors.purple ..style = PaintingStyle.stroke ..strokeCap = StrokeCap.round; canvas.drawRect(Rect.fromPoints(Offset(0,-100), Offset(160,100)), _helpPaint..strokeWidth=2); } @override bool shouldRepaint(CustomPainter oldDelegate) => false; }