Struct SliverConstraints 

pub struct SliverConstraints {
    pub axis_direction: AxisDirection,
    pub growth_direction: GrowthDirection,
    pub user_scroll_direction: ScrollDirection,
    pub scroll_offset: f64,
    pub preceding_scroll_extent: f64,
    pub overlap: f64,
    pub remaining_paint_extent: f64,
    pub cross_axis_extent: f64,
    pub cross_axis_direction: AxisDirection,
    pub viewport_main_axis_extent: f64,
    pub remaining_cache_extent: f64,
    pub cache_origin: f64,
}

Immutable layout constraints for RenderSliver layout.

Fields

axis_direction: AxisDirection

The direction in which scroll_offset and remaining_paint_extent increase.

growth_direction: GrowthDirection

The direction in which the contents of slivers are ordered.

user_scroll_direction: ScrollDirection

The direction in which the user is attempting to scroll.

scroll_offset: f64

Scroll offset in this sliver’s coordinate system of the earliest visible part of this sliver.

preceding_scroll_extent: f64

Scroll distance consumed by all slivers that came before this one.

overlap: f64

Pixels from the painted scroll_offset up to the first pixel not yet painted by an earlier sliver.

remaining_paint_extent: f64

Pixels of content the sliver should consider providing.

cross_axis_extent: f64

Pixels in the cross-axis.

cross_axis_direction: AxisDirection

Direction in which children should be placed in the cross axis.

viewport_main_axis_extent: f64

Pixels the viewport can display in the main axis.

remaining_cache_extent: f64

How much content the sliver should provide starting from cache_origin.

cache_origin: f64

Where the cache area starts relative to the scroll_offset. Always negative or zero.

Implementations

impl SliverConstraints

pub const fn new( axis_direction: AxisDirection, growth_direction: GrowthDirection, user_scroll_direction: ScrollDirection, scroll_offset: f64, preceding_scroll_extent: f64, overlap: f64, remaining_paint_extent: f64, cross_axis_extent: f64, cross_axis_direction: AxisDirection, viewport_main_axis_extent: f64, remaining_cache_extent: f64, cache_origin: f64, ) -> SliverConstraints

Creates sliver constraints with the given information.

pub const fn copy_with(self) -> SliverConstraints

Creates a copy of this object. Chain field replacements.

pub const fn axis_direction(self, value: AxisDirection) -> SliverConstraints

Sets axis_direction.

pub const fn growth_direction(self, value: GrowthDirection) -> SliverConstraints

Sets growth_direction.

pub const fn user_scroll_direction( self, value: ScrollDirection, ) -> SliverConstraints

Sets user_scroll_direction.

pub const fn scroll_offset(self, value: f64) -> SliverConstraints

Sets scroll_offset.

pub const fn preceding_scroll_extent(self, value: f64) -> SliverConstraints

Sets preceding_scroll_extent.

pub const fn overlap(self, value: f64) -> SliverConstraints

Sets overlap.

pub const fn remaining_paint_extent(self, value: f64) -> SliverConstraints

Sets remaining_paint_extent.

pub const fn cross_axis_extent(self, value: f64) -> SliverConstraints

Sets cross_axis_extent.

pub const fn cross_axis_direction( self, value: AxisDirection, ) -> SliverConstraints

Sets cross_axis_direction.

pub const fn viewport_main_axis_extent(self, value: f64) -> SliverConstraints

Sets viewport_main_axis_extent.

pub const fn remaining_cache_extent(self, value: f64) -> SliverConstraints

Sets remaining_cache_extent.

pub const fn cache_origin(self, value: f64) -> SliverConstraints

Sets cache_origin.

pub fn axis(self) -> Axis

The axis along which the scroll offset is measured.

pub fn normalized_growth_direction(self) -> GrowthDirection

growth_direction as if the axis were down or right.

pub fn as_box_constraints( self, min_extent: f64, max_extent: f64, cross_axis_extent: Option<f64>, ) -> BoxConstraints

BoxConstraints that reflect these sliver constraints.

Dart named defaults: min_extent 0, max_extent infinity, cross_axis_extent this sliver’s cross extent.

Trait Implementations

impl Clone for SliverConstraints

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Constraints for SliverConstraints

fn is_tight(&self) -> bool

Whether there is exactly one size possible given these constraints.

fn is_normalized(&self) -> bool

Whether the constraint is expressed in a consistent manner.

fn debug_assert_is_valid(&self, is_applied_constraint: bool) -> bool

Asserts that the constraints are valid.

impl Copy for SliverConstraints

impl Debug for SliverConstraints

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

Formats the value using the given formatter.

impl PartialEq for SliverConstraints

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

Equality operator ==.

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

Inequality operator !=.