How to animated border of container in flutter

Question

I want to draw animated border around the square container with infinity loop (never stop) like this photo , I'm trying animated container bust not help me

so can anyone tell me how to implement line animation

Edit **

I'm using this code to draw the square but I can't make it build with animation

class RadialPainter extends CustomPainter {
  final double progressRemoval;
  final Color color;
  final StrokeCap strokeCap;
  final PaintingStyle paintingStyle;
  final double strokeWidth;
  final double progress;
  RadialPainter(
      {this.progressRemoval,
      this.color,
      this.strokeWidth,
      this.strokeCap,
      this.paintingStyle,
      this.progress});

  @override
  void paint(Canvas canvas, Size size) {
    Paint paint = Paint()
      ..strokeWidth = strokeWidth
      ..color = color
      ..style = paintingStyle
      ..strokeCap = strokeCap;

    var progressRemoval = 0.50;

    var path = Path();

    //LINEA SUPERIOR DEL CUADRADO
    path.moveTo((size.width * 0.30), 0);
    path.quadraticBezierTo((size.width * 0.30), 0, size.width, 0);

    //LATERAL DERECHO
    path.moveTo(size.width, 0);
    path.quadraticBezierTo(size.width, 0, size.width, size.height);

    //LINEA INFERIOR DEL CUADRADO
    path.moveTo(size.width, size.height);
    path.quadraticBezierTo(size.width, size.height, 0, size.height);

    //LINEA IZQUIERDA
    path.moveTo(0, size.height);
    path.quadraticBezierTo(0, (size.height * 0.75), 0, ((size.height * 0.75)));

    canvas.drawPath(path, paint);
  }

  @override
  bool shouldRepaint(RadialPainter oldDelegate) {
    return oldDelegate.progress != progress;
  }
}

enter link description here