books

assets/draw/p05/s03.dart

@@ -0,0 +1,54 @@
+import 'dart:math';
+import 'package:flutter/material.dart';
+
+import '../components/coordinate.dart';
+
+/// create by 张风捷特烈 on 2020-03-19
+/// contact me by email 1981462002@qq.com
+/// 说明: 纸
+
+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();
+
+  @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.purpleAccent
+      ..strokeWidth = 2
+      ..style = PaintingStyle.stroke;
+    var rect = Rect.fromCenter(center: Offset(0, 0), width: 160, height: 100);
+
+    path.lineTo(30, 30);
+    path..arcTo(rect, 0, pi * 1.5, true);
+    canvas.drawPath(path, paint);
+
+    path.reset();
+    canvas.translate(200, 0);
+    path.lineTo(30, 30);
+    path..arcTo(rect, 0, pi * 1.5, false);
+    canvas.drawPath(path, paint);
+  }
+
+  @override
+  bool shouldRepaint(CustomPainter oldDelegate) => false;
+}