flutter_SanDev_customPainter

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    // return Center(
    //   child: CustomPaint(),
    // );
    return MaterialApp(
      title: 'Material App',
      home: Scaffold(
        appBar: AppBar(
          title: Text('Material App Bar'),
        ),
        body: Column(
          children: [
            // Container(child: RaisedButton()),
            Container(
              child: Stack(
                children: [
                  Container(
                    color: Colors.red,
                    child: CustomPaint(
                      painter: MyPainter3(),
                    ),
                  ),
                  Container(
                    color: Colors.red,
                    child: CustomPaint(
                      painter: MyPainter2(),
                    ),
                  ),
                  Container(
                    color: Colors.yellow,
                    child: CustomPaint(
                      painter: MyPainter(),
                    ),
                  ),
                  // Container(
                  //   margin: EdgeInsets.only(top: 200),
                  //   height: 300,
                  //   color: Colors.green.withOpacity(0.4),
                  //   child: CustomPaint(
                  //     painter: MyStar(),
                  //   ),
                  // )
                ],
              ),
            ),
            // Container(child: RaisedButton())
          ],
        ),
      ),
    );
  }
}

class MyStar extends CustomPainter {
  @override
  void paint(Canvas canvas, Size size) {
    // final left = 50.0;
    // final top = 100.0;
    // final right = 250.0;
    // final bottom = 200.0;
    // final rect = Rect.fromLTRB(left, top, right, bottom);
    var paint = Paint();
    //   ..color = Colors.black
    //   ..style = PaintingStyle.stroke
    //   ..strokeWidth = 4;
    // canvas.drawRect(rect, paint);
  }

  @override
  bool shouldRepaint(covariant CustomPainter oldDelegate) {
    // TODO: implement shouldRepaint
    return false;
  }
}

class MyPainter3 extends CustomPainter {
  @override
  void paint(Canvas canvas, Size size) {
    var paint = Paint();
    paint.color = Colors.red;

    paint.style = PaintingStyle.fill;
    var path = Path();
    path.moveTo(0, size.height * 0.8);
    path.quadraticBezierTo(10, 400, 550, 0);
    //path.quadraticBezierTo(0, 500, 300, 0);

    canvas.drawPath(path, paint);
  }

  @override
  bool shouldRepaint(covariant CustomPainter oldDelegate) {
    return false;
  }
}

class MyPainter2 extends CustomPainter {
  @override
  void paint(Canvas canvas, Size size) {
    var paint = Paint();
    paint.color = Colors.yellow;

    paint.style = PaintingStyle.fill;
    var path = Path();
    path.moveTo(0, size.height * 0.8);
    path.quadraticBezierTo(10, 360, 510, 0);
    //path.quadraticBezierTo(0, 500, 300, 0);

    canvas.drawPath(path, paint);
  }

  @override
  bool shouldRepaint(covariant CustomPainter oldDelegate) {
    // TODO: implement shouldRepaint
    return false;
  }
}

class MyPainter extends CustomPainter {
  @override
  void paint(Canvas canvas, Size size) {
    var paint = Paint();
    paint.color = Colors.blue;

    paint.style = PaintingStyle.fill;
    var path = Path();
    path.moveTo(0, size.height * 0.8);
    path.quadraticBezierTo(0, 300, 500, 0);
    //path.quadraticBezierTo(0, 500, 300, 0);

    canvas.drawPath(path, paint);
  }

  @override
  bool shouldRepaint(covariant CustomPainter oldDelegate) {
    //throw UnimplementedError();
    return false;
  }
}