books

assets/draw/p03/s01.dart

@@ -0,0 +1,45 @@
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter/services.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 {
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    var paint = Paint()
+      ..style = PaintingStyle.fill
+      ..color = Colors.blue;
+    // 画布起点移到屏幕中心
+    canvas.translate(size.width / 2, size.height / 2);
+    canvas.drawCircle(Offset(0, 0), 50, paint);
+    canvas.drawLine(
+        Offset(20, 20),
+        Offset(50, 50),
+        paint
+          ..color = Colors.red
+          ..strokeWidth = 5
+          ..strokeCap = StrokeCap.round
+          ..style = PaintingStyle.stroke);
+  }
+
+  @override
+  bool shouldRepaint(CustomPainter oldDelegate) => false;
+}