绘制点集

lib/paper/paper.dart

@@ -0,0 +1,51 @@
+import 'dart:ui';
+
+import 'package:flutter/material.dart';
+
+
+import 'paper_app_bar.dart';
+
+class Paper extends StatefulWidget {
+  const Paper({Key? key}) : super(key: key);
+
+  @override
+  State<Paper> createState() => _PaperState();
+}
+
+class _PaperState extends State<Paper> {
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: PaperAppBar(onClear: _clear,),
+      body: CustomPaint(
+        painter: PaperPainter(),
+        child: ConstrainedBox(constraints: const BoxConstraints.expand()),
+      ),
+    );
+  }
+
+  void _clear() {
+
+  }
+}
+
+class PaperPainter extends CustomPainter{
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    List<Offset> points = const [
+      Offset(100,100),
+      Offset(100,150),
+      Offset(150,150),
+      Offset(200,100),
+    ];
+
+    Paint paint = Paint();
+    paint.strokeWidth = 10;
+    canvas.drawPoints(PointMode.polygon, points , paint);
+  }
+
+  @override
+  bool shouldRepaint(covariant CustomPainter oldDelegate) => true;
+
+}