Struct BoxDecoration 

pub struct BoxDecoration {
    pub color: Option<Color>,
    pub gradient: Option<LinearGradient>,
    pub border: Option<Border>,
    pub radius: BorderRadius,
    pub shadow: Option<BoxShadow>,
}

The complete decoration of a rectangular box.

The paint order is fixed: shadow → background → border. The background is either flat (color) or a gradient (color → gradient.end). A border with no background paints an outline over transparency; a wholly empty decoration paints nothing at all.

Fields

color: Option<Color>

Background colour, which doubles as the start colour of any gradient.

gradient: Option<LinearGradient>

A linear gradient for the background.

border: Option<Border>

A uniform border.

radius: BorderRadius

Corner radii, per corner.

shadow: Option<BoxShadow>

Drop shadow.

Implementations

impl BoxDecoration

pub fn lerp(self, other: BoxDecoration, t: f32) -> BoxDecoration

The decoration t of the way from self to other — what a decoration transition paints mid-flight. Each part has its own rule, and the rules are the point:

• Colours mix where both sides have one, in the space colours are stated in, as every animated colour in this framework does.
• A part on one side only arrives or leaves; it does not come from nowhere. A fill fades, keeping its hue. A border thickens from nought in its own colour. A shadow grows from under the box as it fades in. Each is the part scaled by how far along it is, which is also what the reference does with a part one side lacks.
• A flat fill is a gradient whose two ends agree, so flat to graded spreads the far end out of the fill rather than laying a gradient over it. Here a gradient starts at the fill colour, so the two always arrive and leave together.
• Corners travel one by one.

The absent colour here is not the absent colour of a text style, and the two rules differ for that reason. A text style that names no colour is asking the theme for one — a real, visible colour — so it holds still rather than fade. A decoration that names no fill paints nothing, so fading is exactly what reaching it means.

t is clamped to 0..=1, and a t that is not a number is no progress: past its ends a colour has nowhere to go, and a decoration whose colours stopped at the end while its corners kept going would be two clocks. At 0 and 1 the answer is the end itself, exactly.

impl BoxDecoration

pub fn filled(color: Color) -> BoxDecoration

A decoration with a flat background.

pub fn radius(self, radius: impl Into<BorderRadius>) -> BoxDecoration

Sets the corner radii — uniform through f32, per corner through BorderRadius.

pub fn border(self, border: Border) -> BoxDecoration

Adds a uniform border.

pub fn shadow(self, shadow: BoxShadow) -> BoxDecoration

Adds a shadow.

pub fn gradient(self, gradient: LinearGradient) -> BoxDecoration

Adds a linear gradient to the background.

pub fn content_padding(&self) -> Insets

The inner margin the border needs — add it to the padding so the content is not eaten by the line. This is what feeds taffy.

pub fn paint_into(&self, scene: &mut Scene, rect: Rect, opacity: f32)

Lowers the decoration into scene primitives, in the fixed order shadow → background → border. opacity (0..=1) modulates every colour, which is how a fade-in works. rect is the box in absolute coordinates.

Trait Implementations

impl Clone for BoxDecoration

fn clone(&self) -> BoxDecoration

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for BoxDecoration

impl Debug for BoxDecoration

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for BoxDecoration

fn default() -> BoxDecoration

Returns the “default value” for a type.

impl PartialEq for BoxDecoration

fn eq(&self, other: &BoxDecoration) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for BoxDecoration