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 StatefulWidget { const Paper({super.key}); @override _PaperState createState() => _PaperState(); } class _PaperState extends State with SingleTickerProviderStateMixin { late AnimationController _controller; @override void initState() { super.initState(); _controller = AnimationController( duration: const Duration(milliseconds: 1000), vsync: this, ) ..repeat() ; } @override void dispose() { _controller.dispose(); super.dispose(); } @override Widget build(BuildContext context) { return Container( color: Colors.white, child: CustomPaint( painter: PaperPainter( CurveTween(curve: Curves.linear).animate(_controller)), ), ); } } class PaperPainter extends CustomPainter { final Animation repaint; PaperPainter(this.repaint) : super(repaint: repaint); double waveWidth = 80; double wrapHeight = 100; double waveHeight = 10; @override void paint(Canvas canvas, Size size) { canvas.translate(size.width / 2, size.height / 2); canvas.clipRect((Rect.fromCenter( center: Offset(waveWidth, 0), width: waveWidth * 2, height: 200.0))); Paint paint = Paint(); Path path = getWavePath(); canvas.translate(-4 * waveWidth + 2 * waveWidth * repaint.value, 0); canvas.drawPath(path, paint..color = Colors.orange); canvas.translate(2*waveWidth* repaint.value, 0); canvas.drawPath(path, paint..color = Colors.orange.withAlpha(88)); } Path getWavePath() { Path path = Path(); 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.relativeQuadraticBezierTo( waveWidth / 2, -waveHeight * 2, waveWidth, 0); path.relativeQuadraticBezierTo( waveWidth / 2, waveHeight * 2, waveWidth, 0); path.relativeLineTo(0, wrapHeight); path.relativeLineTo(-waveWidth * 3 * 2.0, 0); return path; } @override bool shouldRepaint(PaperPainter oldDelegate) => oldDelegate.repaint != repaint; }