blob: f82641c7e4cfa33d46688bf207ab297c5baa39c9 [file] [log] [blame]
// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'dart:math' as math;
import 'package:flutter/foundation.dart';
import 'basic_types.dart';
import 'border_radius.dart';
import 'borders.dart';
import 'edge_insets.dart';
/// A rectangular border with smooth continuous transitions between the straight
/// sides and the rounded corners.
///
/// {@tool snippet}
/// ```dart
/// Widget build(BuildContext context) {
/// return Material(
/// shape: ContinuousRectangleBorder(
/// borderRadius: BorderRadius.circular(28.0),
/// ),
/// );
/// }
/// ```
/// {@end-tool}
///
/// See also:
///
/// * [RoundedRectangleBorder] Which creates rectangles with rounded corners,
/// however its straight sides change into a rounded corner with a circular
/// radius in a step function instead of gradually like the
/// [ContinuousRectangleBorder].
class ContinuousRectangleBorder extends OutlinedBorder {
/// The arguments must not be null.
const ContinuousRectangleBorder({
super.side,
this.borderRadius = BorderRadius.zero,
}) : assert(side != null),
assert(borderRadius != null);
/// The radius for each corner.
///
/// Negative radius values are clamped to 0.0 by [getInnerPath] and
/// [getOuterPath].
final BorderRadiusGeometry borderRadius;
@override
EdgeInsetsGeometry get dimensions => EdgeInsets.all(side.width);
@override
ShapeBorder scale(double t) {
return ContinuousRectangleBorder(
side: side.scale(t),
borderRadius: borderRadius * t,
);
}
@override
ShapeBorder? lerpFrom(ShapeBorder? a, double t) {
assert(t != null);
if (a is ContinuousRectangleBorder) {
return ContinuousRectangleBorder(
side: BorderSide.lerp(a.side, side, t),
borderRadius: BorderRadiusGeometry.lerp(a.borderRadius, borderRadius, t)!,
);
}
return super.lerpFrom(a, t);
}
@override
ShapeBorder? lerpTo(ShapeBorder? b, double t) {
assert(t != null);
if (b is ContinuousRectangleBorder) {
return ContinuousRectangleBorder(
side: BorderSide.lerp(side, b.side, t),
borderRadius: BorderRadiusGeometry.lerp(borderRadius, b.borderRadius, t)!,
);
}
return super.lerpTo(b, t);
}
double _clampToShortest(RRect rrect, double value) {
return value > rrect.shortestSide ? rrect.shortestSide : value;
}
Path _getPath(RRect rrect) {
final double left = rrect.left;
final double right = rrect.right;
final double top = rrect.top;
final double bottom = rrect.bottom;
// Radii will be clamped to the value of the shortest side
// of rrect to avoid strange tie-fighter shapes.
final double tlRadiusX =
math.max(0.0, _clampToShortest(rrect, rrect.tlRadiusX));
final double tlRadiusY =
math.max(0.0, _clampToShortest(rrect, rrect.tlRadiusY));
final double trRadiusX =
math.max(0.0, _clampToShortest(rrect, rrect.trRadiusX));
final double trRadiusY =
math.max(0.0, _clampToShortest(rrect, rrect.trRadiusY));
final double blRadiusX =
math.max(0.0, _clampToShortest(rrect, rrect.blRadiusX));
final double blRadiusY =
math.max(0.0, _clampToShortest(rrect, rrect.blRadiusY));
final double brRadiusX =
math.max(0.0, _clampToShortest(rrect, rrect.brRadiusX));
final double brRadiusY =
math.max(0.0, _clampToShortest(rrect, rrect.brRadiusY));
return Path()
..moveTo(left, top + tlRadiusX)
..cubicTo(left, top, left, top, left + tlRadiusY, top)
..lineTo(right - trRadiusX, top)
..cubicTo(right, top, right, top, right, top + trRadiusY)
..lineTo(right, bottom - brRadiusX)
..cubicTo(right, bottom, right, bottom, right - brRadiusY, bottom)
..lineTo(left + blRadiusX, bottom)
..cubicTo(left, bottom, left, bottom, left, bottom - blRadiusY)
..close();
}
@override
Path getInnerPath(Rect rect, { TextDirection? textDirection }) {
return _getPath(borderRadius.resolve(textDirection).toRRect(rect).deflate(side.width));
}
@override
Path getOuterPath(Rect rect, { TextDirection? textDirection }) {
return _getPath(borderRadius.resolve(textDirection).toRRect(rect));
}
@override
ContinuousRectangleBorder copyWith({ BorderSide? side, BorderRadiusGeometry? borderRadius }) {
return ContinuousRectangleBorder(
side: side ?? this.side,
borderRadius: borderRadius ?? this.borderRadius,
);
}
@override
void paint(Canvas canvas, Rect rect, { TextDirection? textDirection }) {
if (rect.isEmpty) {
return;
}
switch (side.style) {
case BorderStyle.none:
break;
case BorderStyle.solid:
canvas.drawPath(
getOuterPath(rect, textDirection: textDirection),
side.toPaint(),
);
break;
}
}
@override
bool operator ==(Object other) {
if (other.runtimeType != runtimeType) {
return false;
}
return other is ContinuousRectangleBorder
&& other.side == side
&& other.borderRadius == borderRadius;
}
@override
int get hashCode => Object.hash(side, borderRadius);
@override
String toString() {
return '${objectRuntimeType(this, 'ContinuousRectangleBorder')}($side, $borderRadius)';
}
}