Struct ProposalSize 

pub struct ProposalSize {
    pub width: Option<f32>,
    pub height: Option<f32>,
}

A size proposal from parent to child during layout negotiation.

Each dimension can be:

• None - “Tell me your ideal size” (unspecified)
• Some(0.0) - “Tell me your minimum size”
• Some(f32::INFINITY) - “Tell me your maximum size”
• Some(value) - “I suggest you use this size”

Children are free to return any size; the proposal is just a suggestion.

Fields

width: Option<f32>

Width proposal: None = unspecified, Some(f32) = suggested width

height: Option<f32>

Height proposal: None = unspecified, Some(f32) = suggested height

Implementations

impl ProposalSize

pub const UNSPECIFIED: ProposalSize

Unspecified proposal - asks for ideal/intrinsic size.

pub const ZERO: ProposalSize

Zero proposal - asks for minimum size.

pub const INFINITY: ProposalSize

Infinite proposal - asks for maximum size.

pub fn new( width: impl Into<Option<f32>>, height: impl Into<Option<f32>>, ) -> ProposalSize

Creates a ProposalSize from optional width and height.

pub fn width_or(&self, default: f32) -> f32

Returns the width or a default value if unspecified.

pub fn height_or(&self, default: f32) -> f32

Returns the height or a default value if unspecified.

pub const fn with_width(self, width: Option<f32>) -> ProposalSize

Replace only the width, keeping the height.

pub const fn with_height(self, height: Option<f32>) -> ProposalSize

Replace only the height, keeping the width.

Trait Implementations

impl Clone for ProposalSize

fn clone(&self) -> ProposalSize

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ProposalSize

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

Formats the value using the given formatter.

impl Default for ProposalSize

fn default() -> ProposalSize

Returns the “default value” for a type.

impl PartialEq for ProposalSize

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for ProposalSize

impl StructuralPartialEq for ProposalSize