How to draw the line with sharp ends /gradient line/ in flutter?

Use CustomPainter to draw:

import 'package:flutter/material.dart';

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

class Example extends StatefulWidget {
  @override
  _ExampleState createState() => _ExampleState();
}

class _ExampleState extends State<Example> {
  @override
  void initState() {
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
        home: Scaffold(
            body: Center(
      child: CustomPaint(
        size: Size(200, 5),
        painter: CurvePainter(),
      ),
    )));
  }

  @override
  void dispose() {
    super.dispose();
  }
}

class CurvePainter extends CustomPainter {
  @override
  void paint(Canvas canvas, Size size) {
    var paint = Paint();
    paint.color = Colors.black;
    paint.style = PaintingStyle.fill; // Change this to fill

    var path = Path();

    path.moveTo(0, 0);
    path.quadraticBezierTo(size.width / 2, size.height / 2, size.width, 0);
    path.quadraticBezierTo(size.width / 2, -size.height / 2, 0, 0);

    canvas.drawPath(path, paint);
  }

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

modified sleepingkit answer:

import 'package:flutter/material.dart';

class PointedLinePainter extends CustomPainter {
  final double width;

  PointedLinePainter(this.width);

  @override
  void paint(Canvas canvas, Size size) {
    var paint = Paint();
    paint.color = Colors.white;
    paint.style = PaintingStyle.fill;

    var path = Path();

    path.moveTo(0, 0);
    path.quadraticBezierTo(width / 3, 0.5, width, 0);
    path.quadraticBezierTo(width / 3, -0.5, 0, 0);

    canvas.drawPath(path, paint);
  }

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

somewhere in code:

Container(
      margin: EdgeInsets.symmetric(horizontal: 10.0),
      alignment: Alignment.centerLeft,
      width: MediaQuery.of(context).size.width,
      height: 2,
      child: CustomPaint(
        painter:
            PointedLinePainter(width - 2 * horizontalPointedLineMargin),
      ),
    )

Can't see your picture.You can use the CustomPaint widget to draw lines, define a class that extends CustomPainter, and use the canvas.drawLine() method.

Divider class

A thin horizontal line, with padding on either side.

In the material design language, this represents a divider. Dividers can be used in lists, Drawers, and elsewhere to separate content.

To create a divider between ListTile items, consider using ListTile.divideTiles, which is optimized for this case.

The box's total height is controlled by height. The appropriate padding is automatically computed from the height.

    [![// Flutter code sample for Divider

// This sample shows how to display a Divider between an orange and blue box
// inside a column. The Divider is 20 logical pixels in height and contains a
// vertically centered black line that is 5 logical pixels thick. The black
// line is indented by 20 logical pixels.
//
// !\[\](https://flutter.github.io/assets-for-api-docs/assets/material/divider.png)

import 'package:flutter/material.dart';

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

/// This Widget is the main application widget.
class MyApp extends StatelessWidget {
  static const String _title = 'Flutter Code Sample';

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: _title,
      home: Scaffold(
        appBar: AppBar(title: const Text(_title)),
        body: MyStatelessWidget(),
      ),
    );
  }
}

/// This is the stateless widget that the main application instantiates.
class MyStatelessWidget extends StatelessWidget {
  MyStatelessWidget({Key key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Column(
        children: <Widget>\[
          Expanded(
            child: Container(
              color: Colors.amber,
              child: const Center(
                child: Text('Above'),
              ),
            ),
          ),
          const Divider(
            color: Colors.black,
            height: 20,
            thickness: 5,
            indent: 20,
            endIndent: 0,
          ),
          Expanded(
            child: Container(
              color: Colors.blue,
              child: const Center(
                child: Text('Below'),
              ),
            ),
          ),
        \],
      ),
    );
  }
}]

Here info how to change style enter link description here