BoxBorder class abstract

Base class for box borders that can paint as rectangles, circles, or rounded rectangles.

This class is extended by Border and BorderDirectional to provide concrete versions of four-sided borders using different conventions for specifying the sides.

The only API difference that this class introduces over ShapeBorder is that its paint method takes additional arguments.

See also:



Abstract const constructor. This constructor enables subclasses to provide const constructors so that they can be used in const expressions.


bottom BorderSide
The bottom side of this border.
no setter
dimensions EdgeInsetsGeometry
The widths of the sides of this border represented as an EdgeInsets.
no setterinherited
hashCode int
The hash code for this object.
no setterinherited
isUniform bool
Whether all four sides of the border are identical. Uniform borders are typically more efficient to paint.
no setter
preferPaintInterior bool
Reports whether paintInterior is implemented.
no setteroverride
runtimeType Type
A representation of the runtime type of the object.
no setterinherited
top BorderSide
The top side of this border.
no setter


add(ShapeBorder other, {bool reversed = false}) BoxBorder?
Attempts to create a new object that represents the amalgamation of this border and the other border.
getInnerPath(Rect rect, {TextDirection? textDirection}) Path
Create a Path that describes the inner edge of the border.
getOuterPath(Rect rect, {TextDirection? textDirection}) Path
Create a Path that describes the outer edge of the border.
lerpFrom(ShapeBorder? a, double t) ShapeBorder?
Linearly interpolates from another ShapeBorder (possibly of another class) to this.
lerpTo(ShapeBorder? b, double t) ShapeBorder?
Linearly interpolates from this to another ShapeBorder (possibly of another class).
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
paint(Canvas canvas, Rect rect, {TextDirection? textDirection, BoxShape shape = BoxShape.rectangle, BorderRadius? borderRadius}) → void
Paints the border within the given Rect on the given Canvas.
paintInterior(Canvas canvas, Rect rect, Paint paint, {TextDirection? textDirection}) → void
Paint a canvas with the appropriate shape.
scale(double t) ShapeBorder
Creates a copy of this border, scaled by the factor t.
toString() String
A string representation of this object.


operator +(ShapeBorder other) ShapeBorder
Creates a new border consisting of the two borders on either side of the operator.
operator ==(Object other) bool
The equality operator.

Static Methods

lerp(BoxBorder? a, BoxBorder? b, double t) BoxBorder?
Linearly interpolate between two borders.
paintNonUniformBorder(Canvas canvas, Rect rect, {required BorderRadius? borderRadius, required TextDirection? textDirection, BoxShape shape = BoxShape.rectangle, BorderSide top = BorderSide.none, BorderSide right = BorderSide.none, BorderSide bottom = BorderSide.none, BorderSide left = BorderSide.none, required Color color}) → void
Paints a Border with different widths, styles and strokeAligns, on any borderRadius while using a single color.