paint method

@override void paint(Canvas canvas, Rect rect, { double? gapStart, double gapExtent = 0.0, double gapPercentage = 0.0, TextDirection? textDirection, })

Paint this input border on canvas.

The rect parameter bounds the InputDecorator's container.

The additional gap parameters reflect the state of the InputDecorator's floating label. When an input decorator gains the focus, its label animates upwards, to make room for the input child. The gapStart and gapExtent parameters define a floating label width interval, and gapPercentage defines the animation's progress (0.0 to 1.0).

Implementation

@override
void paint(
  Canvas canvas,
  Rect rect, {
  double? gapStart,
  double gapExtent = 0.0,
  double gapPercentage = 0.0,
  TextDirection? textDirection,
}) {
  assert(gapPercentage >= 0.0 && gapPercentage <= 1.0);
  assert(_cornersAreCircular(borderRadius!));

  final RRect outer = borderRadius!.toRRect(rect);

  final RRect center = outer.deflate(borderSide.width);

  final shadowPaint = Paint();

  final shaderRect = rect.deflate(borderSide.width);
  shadowPaint
    ..maskFilter = MaskFilter.blur(BlurStyle.normal, 2 + borderSide.width)
    ..shader = LinearGradient(
        begin: FractionalOffset.topCenter,
        end: FractionalOffset.bottomCenter,
        colors: [
          AppColors.darkShadowColor,
          AppColors.lightShadowColor,
        ],
        stops: const [
          0,
          1
        ]).createShader(shaderRect);

  canvas.save();
  canvas.clipRRect(center);
  canvas.drawPath(
      _calculateShadowPath(center, 5 - borderSide.width), shadowPaint);
  canvas.restore();
}