A better way to make a custom curved app bar in flutter

Issue

I am trying to make a custom curved app bar, look like the example below

and after many tries here is my shot

source code :

class CustomShapeBorder extends ContinuousRectangleBorder {
  @override
  Path getOuterPath(Rect rect, {TextDirection textDirection}) {
    final double innerCircleRadius = 150.0;

    Path path = Path();
    path.lineTo(0, rect.height);
    path.cubicTo(rect.width / 1.5 - 40, rect.height + innerCircleRadius - 40, rect.width / 1.5 + 40,
        rect.height + innerCircleRadius - 40, rect.width / 1.5 + 75, rect.height + 50);
    path.quadraticBezierTo(
        rect.width / 1.5 + (innerCircleRadius / 2) + 30, rect.height + 35, rect.width, rect.height);
    path.lineTo(rect.width, 0.0);
    path.close();

    return path;
  }
}

is there an easy way to make it for example SVG.

Solution

I could come up with this result:

Here is the Path:

double x = 150, y = 45, r = 0.5;
Path path = Path()
  ..addRRect(RRect.fromRectAndCorners(rect))
  ..moveTo(rect.bottomRight.dx - 30, rect.bottomCenter.dy)
  ..relativeQuadraticBezierTo(((-x / 2)+(x/6)) * (1 - r), 0, -x / 2 * r, y * r)
  ..relativeQuadraticBezierTo(-x / 6 * r, y * (1 - r), -x / 2 * (1 - r), y * (1 - r))
  ..relativeQuadraticBezierTo(((-x / 2)+(x/6)) * (1 - r), 0, -x / 2 * (1 - r), -y * (1 - r))
  ..relativeQuadraticBezierTo(-x/6*r , -y * r, -x / 2 * r, -y * r);

And here is a good article to see the basics to make shapes: Paths in Flutter: A Visual Guide

Answered By – Pablo Barrera

Answer Checked By – Willingham (FlutterFixes Volunteer)