books

assets/draw/p05/s06.dart

@@ -0,0 +1,88 @@
+
+import 'dart:ui';
+
+import 'package:flutter/material.dart';
+
+import '../components/coordinate.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();
+
+  final Offset p1 = Offset(100, -100);
+  final Offset p2 = Offset(160, 50);
+
+
+  @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;
+
+    path.quadraticBezierTo(p1.dx, p1.dy, p2.dx, p2.dy);
+    _drawHelper(canvas);
+
+    path.relativeQuadraticBezierTo(p1.dx, p1.dy, p2.dx, p2.dy);
+    canvas.drawPath(path, paint);
+
+  }
+
+  void _drawHelper(Canvas canvas) {
+    canvas.drawPoints(
+        PointMode.polygon,
+        [
+          Offset.zero,
+          p1,
+          p2,
+          p1.translate(160, 50),
+          p2.translate(160, 50),
+        ],
+        Paint()
+          ..strokeWidth = 1
+          ..strokeCap = StrokeCap.round
+          ..color = Colors.blue);
+    canvas.drawPoints(
+        PointMode.points,
+        [
+          Offset.zero,
+          p1,
+          p2,
+          p1.translate(160, 50),
+          p2.translate(160, 50),
+        ],
+        Paint()
+          ..strokeWidth = 6
+          ..strokeCap = StrokeCap.round
+          ..color = Colors.blue);
+  }
+
+  @override
+  bool shouldRepaint(CustomPainter oldDelegate) => false;
+}